Beikoff v Queensland Building and Construction Commission [2020] QCAT 377
QUEENSLAND CIVIL AND
ADMINISTRATIVE TRIBUNAL
CITATION: Beikoff v Queensland Building and Construction
Commission [2020] QCAT 377
PARTIES: ANGELINE BEIKOFF
(applicant)
v
QUEENSLAND BUILDING AND CONSTRUCTION
COMMISSION
(respondent)
APPLICATION NO/S: GAR416-18
MATTER TYPE: General administrative review matters
DELIVERED ON: 22 September 2020
HEARING DATES: 21 October 2019
27 November 2019
HEARD AT: Brisbane
DECISION OF: Member Paratz AM
ORDERS: The decision of the Queensland Building and
Construction Commission made on 8 June 2018 to not
issue a Direction to Rectify is confirmed.
CATCHWORDS: CONTRACTS – BUILDING, ENGINEERING AND
RELATED CONTRACTS – PERFORMANCE OF
WORK – REMEDIES FOR BREACH OF CONTRACT -
where an application for review of a decision to not issue
a direction to rectify was made – where moisture was
entering the edge of a house slab – whether the builder
had placed fill against the edge of the slab – whether a
builder is required to extend a membrane up the external
edge of a waffle pod slab – where the Queensland
Building and Construction Commission was urged to
investigate moisture issues in relation to waffle pod slabs,
and to issue consumer warnings, and to consider changes
required to the Australian Standard and the Building Code
of Australia
Australian Standard 2870
Building Code of Australia 2016 Vol 2
Queensland Building and Construction Commission Act
1991 (Qld), s 3(c)
APPEARANCES &
REPRESENTATION:
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Applicant: Self-represented
Respondent: S Nean (In-House Solicitor, QBCC)
REASONS FOR DECISION
[1] Ms Beikoff and Mr Beikoff (‘the owners’) contracted with Ownit Homes Pty Ltd (‘the
builder’) on 21 July 2017 to build a new house at Helensvale in Queensland.1
[2] The house was a single story slab on ground construction. The concrete slab was
constructed using what is known as a ‘waffle pod’ method, which involves the use of
polystyrene foam blocks to act as forms on the ground.
[3] The house was handed over to the owners by the builder on 22 February 2018.2
[4] The owners carried out landscaping works on 16 March 2018.3
[5] On 8 May 2018 the Ms Beikoff contacted the builder by email about rising damp and
efflorescence which she observed on the concrete in the garage of the property and
the store room area.4
[6] The owners made a complaint to the Queensland Building and Construction
Commission (‘QBCC’) on 8 June 2018 in respect of the rising damp.
[7] The QBCC made a decision not to issue a Direction to Rectify to the builder on 24
September 2018. The owners made an application to the QBCC for an internal review
of that decision on 7 October 2018.
[8] The QBCC made an internal review decision on 31 October 2018 not to issue a
Direction to Rectify.
[9] The owners filed an application to review a decision, in relation to the decision of the
QBCC made on 31 October 2018.
[10] The matter was heard by oral hearing on 21 October 2019 and 27 November 2019. At
the conclusion of the hearing I gave directions for the filing of submissions. The
submissions were received by 31 January 2020. The matter was subsequently referred
for a decision.
[11] This is the decision in relation to the Application to Review a Decision.
Nature of the dispute
[12] The use of waffle pods is widespread in the Queensland residential construction
industry. There are advantages in cost saving in labour and time in using this method.
Waffle pod slabs sit on top of the ground. They have particular application where
building on well-compacted flat sites which have good drainage away from the
building in all directions. The method replaces the traditional method of using bedding
sand and in-ground footings to form a slab.
1 Affidavit of Angeline Beikoff dated 25 February 2019, Annexure A.
2 Ibid [2].
3 Ibid [3].
4 Ibid [5].
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[13] This matter concerns the absence of a membrane as a vapour barrier to protect the
edge of the slab from water intrusion.
[14] The essence of the owners’ claim is that the builder did not provide a membrane that
did this, and placed fill against the edge of the slab and that, as a result, water has
entered the slab which is porous, and moisture has risen from there.
[15] The essence of the builder’s position is that it was not required by any relevant
Australian Standard, or similar regulatory provision, to provide such a vapour barrier
in the case of a waffle pod construction, and that the problems have arisen because
the owners placed fill against the edge of the slab in the course of landscaping.
[16] There are factual disputes as to who placed fill material against the edge of the slab:
(a) The builder had a contractor conduct a final tidy up and levelling before
handover. There are questions as to the extent of that work and whether fill was
moved by that contractor.
(b) The builder says that the owners extensively filled beside the house in the course
of landscaping works, and in doing so did not insert a membrane against the
edge of the slab.
(c) The owners say that they only spread a very thin layer of topsoil when turfing
beside the house.
(d) The owners engaged a pest contractor to insert a perimeter termite barrier
system of permeable piping, and questions arise as to when fill was placed over
that system, as to how much fill was placed, and as to who placed that fill.
(e) A possibility is suggested that the builder or landscaper of the adjoining block
may have pushed fill onto the owners’ block.
Complaint to QBCC
[17] Ms Beikoff stated that approximately 10 weeks after occupancy of the dwelling and
moderate rainfall, she and her husband observed efflorescence and rising damp in the
garage area and storeroom area of the residence.5
[18] The builder engaged Morgan Consulting Engineers, who had done the structural
design of the building in 2017, to inspect the reported water ingress. They carried out
a walkover inspection on 14 May 2018, and an invasive inspection on 29 May 2018.
They noted the following matters on their inspection:6
2.2 External
The ground around much of the residence was near level and poorly drained.
The ground along the western side of the garage sloped away from the residence
(photograph 2). During the invasive investigation a small excavation was
carried out along this side of the driveway. This investigation revealed that the
soil was in direct contact with the slab and that the plastic vapour barrier
protruded a short distance from the edge of the slab (photograph 3). Moisture
meter readings indicated a moisture content in the slab edge of approximately
23%.
5 Ibid [4].
6 Morgan Consulting Engineers’ Structural Inspection Report, 6 June 2018, p 2.
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Discolouration was also noted to the rendered slab edge along the rear patio.
Efflorescence and mineral deposits were noted along a line that appeared to
correlate with the base of the tiles (photographs 4 and 5). Moisture meter
readings indicated elevated moisture along this line compared to the remainder
of the slab edge.
2 .3 Internal
The interior of the residence was generally in good condition. Evidence of
moisture and efflorescence was noted along the western wall of the garage
(photographs 6 and 7). The extent of wetting along the edge of the garage had
reduced by the time of our follow-up inspection. Moisture meter readings found
the moisture content along this edge of the slab to be approximately 23%, while
the moisture content toward the centre of the wall was approximately 13%.
During the invasive investigation a hole was cut in the plasterboard linings of
the western wall of the garage in an area where the slab edge was wet. This
investigation revealed that the timber framing, ply bracing, brickwork and
sarking on the wall cavity were all dry (photographs 8 and 9). Moisture meter
readings of the various materials very [sic] between 10 – 15%.
Inspection of the storage room under the stairs on the eastern side of the
residence found a slight discolouration along the edge of the slab (photograph
10). A sealant had been applied along the base of the doorframe (photograph
11). Moisture meter readings showed that the moisture level was consistent
internally and along the edges, with readings of approximately 11 – 13%
[19] The owners made a complaint to the QBCC on 8 June 2018, and a QBCC building
inspector, Mr Steve Jeynes, inspected the premises on 21 August 2018, and reported
as to the damage:7
A visual inspection was undertaken to the garage floor and surrounding
building, which revealed:
There was evidence of minor rising damp and efflorescence to the garage floor
adjacent the side wall (Western side external wall) and to the storeroom (eastern
side)
and
It should be noted that the garage/storeroom is a non-–habitable area under the
Building Code of Australia. There was no evidence of moisture damage
internally to the remainder of the house.
[20] Mr Jeynes noted the extent of the vapour barrier as follows:8
The underslab damp proof course (plastic vapour barrier) protruded a short
distance from the outer edge of the slab/footing. This system is in accordance
with AS 2780 residential slabs and footings (vapour barrier may terminate here
with local acceptance (see clause 5.3.3(b)). There was no DPC between the edge
of the slab/footing and the landscape soil.
[21] Mr Jeynes concluded that it was not appropriate to issue a Direction to Rectify:9
Item 1 of your complaint form has been investigated and there was insufficient
evidence to reveal any obvious defective construction practices by Ownit
7 Resolution Services’ Initial Inspection Report, 21 September 2018, p 4.
8 Ibid, p. 4.
9 Ibid, p. 4.
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Homes Pty Ltd at the time of inspection. It is not considered fair or reasonable
under the QBCC Board Policy to send the Licensee a direction at this time.
[22] The owners applied for an internal review of the decision of Mr Jeynes. The internal
review officer obtained further technical advice from Mr Steven Noble, QBCC Senior
Technical Internal Review Officer.
[23] Mr Noble provided an ‘Internal Review Desktop Report’ dated 29 October 2018. He
noted that he was satisfied that the BCA 2016 Vol 2 was the appropriate code to assess
the construction works in dispute, and that the Rectification of Building Work Policy
which applied was that of 10 October 2014.10
[24] Mr Noble described the situation in relation to the vapour barrier as follows:11
The polyethylene vapour barrier appears to have been installed below the waffle
slab, and surplus vapour barrier is visible to the front right-hand side elevation
of the garage through review of photos in QBCC archives.
However, in review of the photos, surplus vapour barrier is not evident along
the right-hand side of the garage. Interestingly, efflorescence is visible along
the internal garage slab along this elevation. Mr Jeynes has confirmed through
visual inspection of an existing wall vent that the garage structural frame along
this wall is dry and no sign of deterioration despite evidence of slab edge
dampness manifesting as efflorescence.
While it is appreciated that invasive investigation may provide a clear
understanding of the extent to which the slab edge dampness has affected the
structural frame, it is reasonable to conclude that the underlying issue is the
absence of the vapour barrier extending above the finished ground to this
elevation.
[25] Mr Noble noted that other parties undertook the landscaping, and that it was the
responsibility of the persons undertaking those works to ensure that the requisite
standards of AS 2870 were not contravened:12
Of particular interest is that other parties undertook the landscaping. Prior to the
landscaping works commencing, the finished ground level was approximately
150mm below the slab edge rebate, or 150mm below the weep holes to the
masonry veneer. The landscaping works completed after this has reduced this
margin. Please refer to the pictures provided below by way of comparison.
Prior to undertaking the landscaping works, the responsible party undertaking
the proposed works must first confirm that the preceding works is fit for
purpose, and that proceeding with the landscaping will not contravene requisite
standards of AS 2870.
When parties ascertain that proceeding with landscaping will result in
contravention of Australian Standards, it is incumbent on them to notify the
respective parties and seek remediation of the issue prior to commencing with
the landscaping works.
[26] Mr Noble found that it was not possible to apportion responsibility for the non-
compliance with AS 2870:13
10 Internal Review Desktop Report, 29 October 2018, p 1.
11 Ibid, p 2.
12 Ibid, p 2.
13 Ibid, p 2.
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While it is acknowledged that the vapour barrier detailing to the right hand side
of the garage does not comply with AS 2870, apportioning sole responsibility
is not possible where two separate parties have undertaken works within the
same location.
Subject to the evidence at my disposal, I cannot determine beyond reasonable
doubt who caused the slab edge dampness to the garage external wall.
[27] The Internal Review Officer relied upon the report of Mr Noble, and concluded that a
Direction to Rectify should not be issued:14
In the circumstances where the applicant has performed landscaping works and
changed the finished ground level around the property, I cannot be reasonably
satisfied that the defect is the sole responsibility of the affected party.
For this reason, I have decided not to issue a direction to rectify for item 1.
Regulatory provisions
[28] Sections of the Australian Standard 2870 – 2011 Residential slabs and footings (AS
2870) and the National Construction Code Building Code of Australia (BCA/NCC)
are relevant. The object of AS 2870 is to ‘specify performance criteria and specific
designs for footing systems for foundation conditions commonly found in
Australia’.15
[29] The following sections of AS 2870 (5.3.3 Vapour barriers and damp–proofing
membranes) are relevant:
5.3.3.1 General
Where required, the raft or slab shall be provided with a vapour barrier, or a
damp – proofing membrane.
(and)
5.3.3.4 Installation
Both vapour barriers and damp–proofing membranes shall be installed as
follows:
(a) The sheet shall be placed beneath the slab so that the bottom surface of the
slab and beams, including internal beams, is entirely underlaid. The membrane
shall extend under the edge beam to ground level; however, where justified by
satisfactory local experience, a vapour barrier may be terminated at the internal
face of external beams as shown on figure 5.2(a)
14 Decision Notice, 31 October 2018, p 2.
15 AS 2870, p 2.
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(b) Lapping for continuity at joints shall be not less than 200mm
(c) penetrations by pipes or plumbing fittings shall be taped to or sealed with a
close – fitting sleeve or made continuous with the vapour barrier or damp –
proof membrane by taping or by lapping in accordance with item (b)
[30] Functional statement F2.2.2 provides that ‘a building is to be constructed to provide
resistance to moisture from the outside and moisture rising from the ground’.
[31] The following sections of part 2.2 of the BCA/NCC, which deal with damp and
weatherproofing, are relevant:
3.2.2.6 Vapour barriers
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A vapour barrier must be installed under slab-on-ground construction for all
class 1 buildings and for class 10 buildings where the slab is continuous with
the slab of a class 1 building as follows –
…….
[c] The vapour barrier must be placed beneath the slab so that the bottom surface
of the slab is entirely underlaid and extends under edge beams to finish at
ground level in accordance with Figure 3.2.2.3
The owners’ evidence and submissions
[32] Ms Beikoff gave evidence that her property was affected by rising damp. She said that
she first noticed discolouration on the floor along the western side in the garage where
there was just concrete, and after a few days there was actually a sign of efflorescence
following the outline of that discoloration on 8 May 2018. She said that the
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efflorescence was notable in the storage area on the eastern side a couple of weeks
later. 16
[33] Ms Beikoff was asked about the site clean-up conducted by the builder, and said that
it was done on 31 January 2018 by Damo’s Diggers Proprietary Limited who were
engaged by the builder:17
Okay. Can you tell me about the site clean-up? – – We were – this was about
three weeks before handover and we were on site and a bloke turned up with a
bobcat, and he actually asked us if we wanted to keep any of the bricks that
were lying around the place, because he was doing the final clean up, and there
was – he was moving a stockpile of dirt around that clean-up. So yeah, I was
there for that.
[34] Ms Beikoff said that she saw the bobcat driver moving dirt around near the slab:18
Okay. Did you observe the bobcat driver to fold up any Visqueen barrier around
the slab prior to moving the dirt around with the bobcat? – – No.
Okay. Did you observe the bobcat driver to install any further Visqueen barrier
to prevent dirt being moved up and contacting the slab? – – No.
And when the bobcat driver moved dirt around, was it near the slab at all? – –
Yes.
[35] Ms Beikoff said that landscaping was done on 16 March by herself, her husband
Geoffrey, and Dan Arnott, and said that she did not see or touch any vapour barrier:19
Alright. When the landscaping was undertaken, did you see any vapour barrier
around the slab before you commenced landscaping? – – No.
Did you cut or remove any vapour barrier from around the slab during
landscaping? – – No.
Did you fold down any vapour barrier from around the slab during landscaping?
– – No.
Are you aware if you’d covered any vapour barrier with soil so that the soil
would come into – fold the vapour barrier down, the soil would come into
contact with the slab? – – No.
[36] Ms Beikoff said that they had additional termite protection installed after the build.
She looked at photographs, and said they showed the termite reticulation piping run
around the concrete edge, sitting on top of the ground level against the slab, and could
not see any Visqueen barrier in the photograph.20
[37] In cross examination Ms Beikoff was asked about the grading of the soil that was done
for the landscaping, and said that they followed what was done by the builder:21
And you complied with that by building up the ground to make sure it sloped
away?… No, the – there was already soil up against the house and there was –
it was fairly high against the house as it was, so – and we were reaching down
to where the neighbour was because theirs had already been done. So we
16 Transcript 1-24, line 35.
17 Transcript 1-26, line 19.
18 Transcript 1-26, line 40.
19 Transcript 1-27, line 23.
20 Transcript 1-31, line 21.
21 Transcript 1-41, line 15.
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couldn’t go any higher because the slope was marginally – it’s more than 150
mil drop there, so…
Sorry, you said that you ensured that you complied. How did you ensure that
you complied?… We drained away from it. We were actually told that by Ownit
Homes, to make sure that we graded away from the house.
Yes, but how did you achieve the grading?… We used the ground level that was
there at handover, and we used the next door neighbours [sic] final landscaping,
because they had finished it before us, and – so we just pretty well-kept it the
same.
You kept it the same?… We did put some topsoil over it.
Yes?… Yes, but we couldn’t change it very much, because it was too high as it
was.
[38] In relation to material placed against the edge of the slab, Ms Beikoff was asked how
much topsoil was spread under the turf, and agreed that they placed about 35 mm of
soil in total against the edge of the slab.22
[39] She said that she was not able to state how much fill the bobcat driver had placed
against the edge of the slab:23
Do you have any idea what depth of fill the bobcat driver, prior to handover
placed against the edge of the slab?….No. I couldn’t be definite in that. I do
know that, on that Western side, the slope was pretty steep, because it was
difficult even just walking down there, so it was pretty steep to begin with, and
you can see that in the photographs. I do know the bobcat driver didn’t place a
lot at the back because there was a lot of – it was a low-lying area, and, as you
can see in those photographs, there is water lying around.
Did you observe what the bobcat driver was doing there on 31 January 2018?…
Just-he cleaned up the site of bricks and everything, and then he just moved the
stockpile and was just pushing up against the house. I don’t think he made any
effort to fill any lower areas. He just pushed up against the house.
…..24
But you’re not able to estimate the depth of fill that was placed by the bobcat
driver, I think you said?… Yeah, I would be guessing.
Against the edge of the slab?… I would be guessing.
[40] She said she had been given only limited instructions as to how to conduct landscaping
by the builder:25
Did you receive any instructions from the builder as to conduct of landscaping
works after handover?… I was just told by the – our supervisor to ensure that
all landscaping sloped away from the house.
Sloped away?… Here, and not to cover the inspection outlets for the sewerage,
which was – I think we have two.
22 Transcript 1-47, line 34.
23 Transcript 1-47, line 37.
24 Transcript 1-48, line 15.
25 Transcript 1-48, line 20.
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[41] Mr Daniel Arnott assisted with the landscaping work. He said that he was aware at
the time that the ground is not supposed to be above the vapour barrier, that he did not
see any vapour barrier, but proceeded with the landscaping by following the existing
gradient, and that the thickness of the layer of topsoil they spread would have been
‘not even an inch’.26
[42] Mr Geoffrey Beikoff said that he observed a bobcat clean-up around the perimeter of
the housing block as follows:27
And can you describe to me what you observed to take place with that site
cleanup? What happened?….It was primarily a bobcat cleanup around the
perimeter of the housing block
And what did the bobcat do?… He moved scrap – he moves soil – he removed
heavy bulk bricks and stuff away from the site, while also distributing soil up
against the side of the house.
[43] Mr Beikoff said that he did not see any vapour barrier before he commenced the
landscaping.28
[44] In relation to termite control, Mr Beikoff said that there were two types of control,
one that the builder put in, and one that was put in as a reticulation system around the
perimeter of the house afterwards, probably two days after handover at the end of
February or the beginning of March 2018.29 He described the termite conduit as sitting
slightly exposed on top of the ground on the western side near the corner of the garage,
on 24 May after the landscaping was done.30
[45] Mr Beikoff was asked in cross examination about the landscaping work done by the
neighbour and said it was done before he did his landscaping:31
And just to clarify something that I think was a bit new in your evidence-in-
Chief, but I don’t think is in your statement, but correct me if I’m wrong.
Subsequent to this photo being taken, but before you did the landscaping, the
neighbouring property did landscaping. Is that correct?… That’s correct.
And that’s when the fence was installed, also?… Yeah, about the same-yes.
Okay. So is it possible that the – the neighbouring – the neighbours [sic]
landscape affected this at all? Because when I look at this, and this, it’s a bit
different and I apologise for putting you on the spot, but I hadn’t seen any
evidence about the neighbours [sic] landscaping until – until today?… The same
landscaper did their site, the fence on our side. Not the landscaping on our site.
It is possible but maybe unlikely.
26 Transcript 1-56, line 43.
27 Transcript 1-63, line 1.
28 Transcript 1-63, line 44.
29 Transcript 1-64, line 10.
30 Transcript 1-65, line 16.
31 Transcript 1-77, line 44.
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The commission’s evidence and submissions
[46] Mr Bradley Ganim, the managing director of Ownit Homes, gave evidence. He said
that he did not believe that any dirt was spread by the bobcat in the course of the site
clean-up as there was no dirt on site.32
[47] I asked Mr Ganim to describe the usual practice of his company, and he said it was to
extend Visqueen from the bottom of a waffle pod slab:33
Mr Ganim, on the plans for this contract, is there anywhere that you see a
foundation design plan that shows the extent (indistinct) of the (indistinct)
barrier on the outside of the slab?….Sorry, in one of our details, it shows that
we put the Visqueen down and turn it up.
Yes. Is there anything noted on the plan as to the extent that the Visqueen has
been turned up on the outside of the slab?… Not that I’m aware of.
All right. Would that be the usual practice, for your company to provide for
Visqueen to extend out so the bottom of the slab to turn up to come to ground
level?… Yes. More so, in particular, if we’re doing the landscaping.
You know Mr Ian Dennis?… Yes
He is the construction manager for your company, is he?… That’s correct.
And he was a construction manager on this job?….Yes, he was.
All right. I’d like you to look at the statement of reasons (indistinct) tab 2, page
156. Now, at that page, there is an email from Mr Dennis to the Beikoffs dated
17 May 2018. And in the last large paragraph it says:
What Mark was actually making comment on was the plastic Visqueen
that is laid under the slab is fitted. When the concrete sits up to place the
slab, this plastic sheet is laid down on top of his bedding sand and before
the pod is fitted. This is allowed to hang outside the formwork, across the
ground, and there is sufficient sitting external of the slab edge that allows
for it to be turned up the edge of the slab, before any filler is placed
against the slab edge itself. This is to prevent any moisture from the –
within the soils or fill to suck back through the slab edge.
Would you agree that’s the usual practice?… Yes.
[48] Mr Ganim said that he was unable to see any Visqueen extending from the bottom of
the slab in the photographs shown to him:34
Do you have any evidence that the Visqueen was laid out as described by Mr
Dennis in that email on this job?… Not that I can see.
Have you seen any photograph that shows the Visqueen extending at the bottom
of the slab sufficient to be able to fold it up to ground level?… Not in any photos
I’ve seen.
[49] Mr Ganim said that the side of the slab would have been 150 millimetres high:35
32 Transcript 1-94, line 42.
33 Transcript 1-101, line 39.
34 Transcript 1-102, line 24.
35 Transcript 1-103, line 1.
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Well, that’s the plan. I’m more interested in the as constructed?… Well, that’s
a standard profile that the concreters have. That’d be 150, that side of the slab.
So you think – you think that side of the slab would have been 150 from the
plans, but you – can you in any way assess whether it actually is, as constructed,
150?… It would have to be for the engineer to pass it. It’s a standard bracket
the concreters have. It has a 150 millimetre stand up, and that’s the standard
sizing for – for waffle pods.
[50] Mr Ganim said that he was present when his maintenance man dug a hole beside the
slab, and that he did not observe any Visqueen extending from the slab, but that it
seemed that the Visqueen had been torn, and he doubted that was done by the bobcat
driver:36
Now, you say you dug that hole as shown in photograph 3. Did you break off
any of the Visqueen, or observe that the Visqueen extended any further than just
under the bottom edge of the slab, as it seems?… That’s the unknown.
That’s the only?… That’s the unknown.
Well, when you dug down, did you find anywhere that the Visqueen was turned
up to ground level?… No, I did not.
All right?… But you could see it looks like it’s been cut or something’s
happened – well, there is a section on that just to the left of that straight section
that looks like it’s torn.
Right?… But that’s – that’s the unknown, I suppose.
Yes. Could the Visqueen have been torn by the cleanup bobcat driver, as he was
cleaning the site?… I doubt that because it’s the access down that side. I can’t
– you know, the access down the side so – you’ve got to make – the machine
can get down the side there.
[51] Mr Ganim described the fill which he saw in the hole beside the slab:37
Now, when you excavated, that hole, as shown in photograph three, if the
situation was that there had been fill placed next to it you’d expect to see
different stratas of fill – different layers of material. Did you find different layers
of material as you dug that hole? – It’s hard to recollect, but looking at the
photos there it looks like there’s another product there, like, it’s a loosey, grainy
type material.
Yes, it does. Could that be decomposed granite?… Cannot comment.
Is it the sort of material the concreter may have used as a base of the foundations
to fill under the waffle pod as you were referring to earlier?… I don’t know. I
can’t make that assumption. It could also be fill the clients brought in to get the
land, you know, build the land levels up.
Did you find topsoil?… Can’t really remember, but I assume so because we had
there – got some grass.
But in the layers – because essentially this photograph might tell the whole story
because it’s when you dug, it shows no Visqueen up the side, it doesn’t seem to
show any substantial layer of topsoil, unless you can point it out. What it seems
to show is a consistent layer of another material which hasn’t been identified. It
36 Transcript 1-103, line 10.
37 Transcript 1-103, line 35.
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might be broken concrete, it looks like there’s lumps of concrete in the bottom
there, some sort of granular material. But the suggestion is that the homeowners
in the landscaping process have filled above the level that proper construction
would have taken to, which is that ground-level. Is there any evidence of that in
that photo – of landscaping activity filling?… It is certainly some sort of fill the
– looks to be there.
Some sort of fill, but the evidence of…?… It could come you know it could
have come from anywhere. It could have come from even the neighbours [sic]
fence being dug when they dig those holes that, and they put that there as well.
It’s too hard to say. It’s – there’s no definite answer. But what we can see on
photo A – there’s nothing really there at the time of slab.
Do know what the finished level should have been at handover when you look
at that photograph? At what point on the…?… Well, you could also assume –
sorry, Member – that if that – if you’re – what you’re alluding to a little bit – I
mean, it’s an assumption that that could be the crusher dust from the concrete.
Well, that was a question I asked?… Yeah. Oh, right. While it would be there
at time of slab too. So doesn’t look to be there are time of slab, and there is no
– no residue of it around, but you can see from the photos. So I’d say that it’s
come in at a later date, looking at the photos.
[52] Mr Ganim was asked what he considered to be ‘ground level’, and said that he
considered it to be the bottom of the slab:38
Member: Well, where’s ground level shown on the plan you’re referring to? On
page 87 of the plans. At page 87.
Ms Nean: Is that – Mr Ganim, is that straight line with the 385 goes to, is that
ground-level?… Yes, it is. And just to elaborate, you’ll have an RL. I’m just
trying to find that. And that would be – the note says ground-level to, which
will show 385 mil below the slab, which will be the RL on document 77 of the
plans. I haven’t got the. It’s approximate pad level and slab level. So the pad
level is 4050, which would denote as ground-level. In the slab level is 4435,
which is slab level, approximately, which is in the centre of the drawing. So
from your question, I am saying ground-level is 4050, which is the pad – which
is the pad level, which is where we cut the site.
…39
Member: the plan you’re referring to at page 77, Mr Ganim, is the earthworks
plan. It’s the site scrape?… That’s the ground level.
Well, that’s not the finished ground level?… I don’t know what the finished
ground level is, though, when I handed over the job. I’ll have no idea.
But that’s the whole point of this. This is about the vapour barrier going to the
finished ground level?… But that’s not my – you can even see on this diagram
here, you can even see some of the slab exposed. I don’t know. That wasn’t part
of my obligation to do any external works and there are systems and methods
you can do to protect the side of the slab. So when I – you know, from the
photos, from what I’ve ascertained, we’ve handed the house over at the ground
level, which is that pallet, which is the site scrape, which is that pad level.
38 Transcript 1-109, line 9.
39 Transcript 1-109, line 39.
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[53] Mr Steven Noble, the Senior Internal Technical Review Officer for the QBCC, gave
evidence, and referred to the engineer’s drawings for the construction:40
A:… So this – this provides that the engineer had required that that vapour
barrier extend under the whole of the slab itself. And that it terminated outside
that external edge of the slab and not inside the internal edge of that slab.
Q: And it doesn’t show the barrier terminating any specific distance up the side
of the – the – side of the slab?
A: No. It doesn’t show it extending vertically whatsoever. It just – it just denotes
it is extending beyond the slab edge. Now, as discussed before, and I’ll – I’ll
use of page – page – or annexure A, page 5 as an – a good way of indicating
what construction has occurred here, is that the – if you look – if you reference
that – that photo and then you look at the rib – edge rib section of this detail of
which are talking about right now, it shows that inside that (indistinct) that edge
is the waffle section that is provided inside that slab edge rebate. It also shows
that that – that slab is situated on the top of ground. So in a – in a practical sense,
when you are constructing this you would level the site to whatever – whatever
that level height requirement is. You would then install your sand which should
take into consideration any protruberances [sic] or deviations to that plan
through the excavation process, and provide a reasonably flat workable finish
that’s also quite soft. And then that vapour barrier would then be rolled out and
lapped accordingly to the extent of that slab. And then on top of that would be
the formwork which would then be sitting on top of that sand to form up the
external slab edge rebates and the perimeter of that slab. And that’s what we’re
looking at in this photo after the formwork has all been removed. And the – the
slab is clearly sitting on the ground. On level ground upon which the building
platform had been created for that.
[54] Mr Noble went on to describe why the vapour barrier just extends horizontally,
because the slab sits on top of the ground:41
… So the difference between that and the engineering design, because this is a
waffle pad, is that this slab has not been designed to be excavated into the
ground level itself. Rather, it sits on the top and so that vapour barrier doesn’t
need to extend down into a thickening beam within the ground. This vapour
barrier just extends horizontally to the full platform of the building.
[55] I asked Mr Noble what he considered acceptable building practice was as to the extent
of the extension of the Visqueen, and he said that extending to the bottom of the slab
was acceptable, as follows:42
So your view is that it’s acceptable for the builder to have only extended the
membrane to the bottom of the slab as shown in photograph 3 on the Morgan
report?… The engineering design required that the membrane terminates there,
and it’s also a requirement that there is fall from that particular point outside of
that slab to the entire perimeter.
That wasn’t my question. My question was what, in your view, was an
acceptable building practice for the builder. If we look at photographs 3 of the
Morgan report, it looks like the membrane is extended to the bottom of the slab.
Do you consider that the proper building practice?… Yes.
40 Transcript 2-13, line 27.
41 Transcript 2-14, line 23.
42 Transcript 2-17, line 31.
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All right. Well, in that case, let’s stay on photograph 3. The question then
becomes that somebody has piled material above the bottom of the slab, up the
slab edge without there being a membrane running vertically. So that then
becomes a problem, that somebody has done that?… Yeah, somebody has done
that.
[56] Mr Noble said that he was unable to say who placed the fill material that was
observable in the excavation beside the slab:43
All right. So, we still keep coming back to the material that is shown in
photograph 3 of the Morgan report. And this becomes probably the central
question then, who has placed that material there?… Yes, so this is the question
that I’m not able to provide.
All right. That if we…?… And hand on heart I cannot say that it was placed by
the owners or placed by the builder. On the material, it’s a timeline and it’s on
the photos during the course of the construction that I’m looking at as well as
the works, or the subsequent photos, that I’m able to look at. That’s all I can
see. What the landscaper did, who – whether that materials been pushed from
an adjacent lot across, I’ve got no idea.
[57] Mr Noble was asked if it was possible that the neighbour may have pushed some
gravel material from their site, and he thought that was possible:44
We can see in the excavation that there’s got to be a fair suggestion that material
may have come from that pile on the adjoining site but if that adjoining house
was finished earlier that cleanup of that site has pushed some of the gravel
material onto Beikoffs’ site. So, it’s something that hasn’t been done by this
builder or by the Beikoffs but perhaps by the neighbour?… It’s – that’s possible
that that’s the case.
[58] He then referred to some photographs and identified that a builder’s fence between
the two adjoining construction sites was not actually on the boundary, and that fill
may not have been contained on the neighbour’s site from the construction:45
So, well inside the temporary fencing?… Yes. So the temporary fencing has
been put onto that site by Orbit Homes when, in actual fact, that’s not the
boundary. The boundary sits further inside that.
Sorry, you mentioned Orbit Homes, which side are they building?
Right?… That has been placed not on this site but on – actually on the adjoining
site.
So it’s encroaching on the adjoining site?… It’s encroaching on the other side.
There’s a whole lot of timber that you can see there is well which – Clearly the
builder is using it during the course of the construction
Right?….But that fence is on the adjoining site. So when they commenced
building that adjoining site, which is where that red car is poking out of the –
that fenceline would no longer be there, it would be further across towards a
building. So, it is feasible in further reflection that some of that material may
have come from the adjoining site because that clearly – the material that’s been
placed there is clearly in the middle of where the slab would be, that – it’s where
that house currently is, is where that material is. And that would need to be
43 Transcript 2-21, line 44.
44 Transcript 2-23, line 32.
45 Transcript 2-24, line 11.
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spread by machine in order to provide a level building platform, I imagine that’s
what they’re using it for. And it is possible that that can encroach on this
particular site that we’re talking about today.
Discussion
[59] This matter raises significant questions about issues related to the use of waffle pods.
[60] It is clear that the house has been affected by moisture intrusion which is occurring
because soil has been piled against the unprotected edge of the slab, and water has
moved from the soil into the slab edge which is porous.
[61] The question is as to who placed the soil against the edge of the slab, and whether
there should have been a moisture barrier placed by the builder against the edge of the
slab to prevent moisture seeping into it.
[62] The QBCC declined to issue a Direction to Rectify in the first instance, because the
inspector, Mr Jeynes, concluded that there was insufficient evidence to reveal any
obvious defective construction practices by the builder, and that it was considered not
fair or reasonable under the QBCC Board policy to give the builder a direction at that
time.
[63] An internal review by the QBCC confirmed that decision. The internal reviewer
sought advice from Mr Noble, the QBCC Senior Technical Internal Review Officer.
Mr Noble expressed the view that it was not possible to determine who conducted
works without a vapour barrier being present, and referred to ‘two separate parties
who had undertaken works within the same location’.
[64] Mr Noble was referring to the alternatives that either the builder had placed soil
against the unprotected side of the slab; or that the owners had done so when they
placed topsoil and turf beside the house.
[65] The owners steadfastly refused to accept that they had placed any significant quantity
of soil against the side of the slab, and pointed to cleanup works conducted by a bobcat
operator contracted by the builder as having piled soil against the side of the slab.
[66] The owners did not obtain independent engineering advice, and relied upon their
personal observations.
[67] After the owners complained of water intrusion, the builder had an engineering firm,
Morgan Consulting Engineers, conduct investigations. Mr Ganim, the principal of the
builder, described his being present when a hole was dug by the engineer against the
side of the slab.
[68] A photograph of the excavation appears at page 98 of the QBCC statement of reasons.
In my view, that photograph is the key to understanding this matter, and reveals the
mechanisms at play. The photograph shows:
(a) the bottom of the slab with Visqueen visible at the bottom edge of the slab, but
not extending up the side of the slab at all;
(b) a deep layer of material that is a loose grainy material;
(c) a thin top layer of topsoil with grass on it.
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[69] I am satisfied that the builder extended a plastic membrane (Visqueen) under the slab,
which extended to the edge of the slab.
[70] I accept the evidence of the builder that the works conducted by the contractor with a
bobcat would have been minimal, as a site cleanup, to scrape the site clean, but not to
place or move any significant quantities of fill.
[71] I am satisfied that the builder’s contractor did not place any substantial amounts of fill
against the side of the slab.
[72] There is no evidence of any large quantities of topsoil being purchased, or spread by
the owners. I accept the evidence of the owners, and a person who assisted them in
laying topsoil and turf, that they did not place any significant depth of topsoil below
the turf.
[73] I am satisfied that the owners did not place any substantial amounts of topsoil against
the edge of the slab.
[74] Where then, did the deep layer of loose grainy material which is shown in the
photograph, and which is placed against the side of the slab, come from?
[75] In the course of the hearing, and particularly in the course of the evidence of Mr Noble,
two further possibilities emerged as to the source of the fill:
(a) the fill may have been pushed from the adjacent block, where a house was being
constructed at a similar time; or
(b) the fill may have been placed by a termite control contractor engaged by the
owners, after the house was handed over, to install a further system of plastic
piping to distribute a termicide chemical.
[76] No clear evidence was obtained as to what works were performed in relation to the
adjoining block. The owners however referred to a landscaper working on the
adjoining block, and to levels between the two blocks which differed at times, and the
erection of a dividing fence.
[77] Photographs were put in evidence of the owners’ house during construction which
showed a temporary construction fence put in place by the builder of the adjoining
house. Mr Noble’s evidence was that the temporary fence was not on the proper
boundary line, and encroached upon the adjoining block. There was therefore clearly
an overlap of activity between the two blocks.
[78] The dividing fence was built after the builder had handed over the house. The builder
suggested that it may have required the digging of holes for the fence posts, which
would have produced a quantity of fill.
[79] In his evidence, Mr Noble described, as quoted previously, that he considered that it
was feasible ‘in further reflection’ that some of the material may have come from the
adjoining site which would have been spread by machine in order to provide a level
building platform, and it was possible that it could encroach on the owners’ site.
[80] Mr Noble said that the practice of a termite control company would be that generally
they don’t undertake landscaping works, but they are required to ensure that the
system was concealed before being charged chemically, so that it was safe to then
charge with the termite management product used – otherwise they would be risking
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the safety of anybody who may frequent that section of the building where it was
being installed.46
[81] He went on to say that traditionally the termite system would be covered with a
pavement of sorts, to avoid chemical leaching occurring with someone barefoot, for
example, who could walk over it and ingest it.
[82] There is then a possibility that the termite control company may have placed soil over
the termite system. Mr Noble’s evidence was that the reticulation system needs to be
below the surface in order to satisfy the requirement of chemically treating soil, but
he did not indicate that a deep excavation was required, which would entail large
amounts of fill being placed over it and against the edge of the slab.
[83] I consider it unlikely that the termite control company would have moved significant
quantities of fill, as there is no observation of that, and no specification in a contract
with that company for any such work.
[84] I consider that the most likely source of the fill being placed against the slab edge was
by the adjoining builder, or landscaper, pushing fill between the two blocks to create
final levels in preparation for, and in the course of construction of, the boundary fence.
[85] Whilst it cannot be established with certainty as to how the loose grainy material came
to be placed against the edge of the slab of the house, I am satisfied that it was not
done by either the builder or the owners.
[86] The cause of the moisture rising up the walls of the house, which is the owners’
concern, is the absence of a waterproof membrane of any sort along the edge of the
slab. The question then becomes – was it the responsibility of the builder to have
placed a membrane along the edge of the slab before handing the building over?
[87] Mr Noble discussed the engineering design which was provided to the builder, which
only required that the vapour barrier terminate at the external edge of the slab:47
Mr Noble:… So this is the – this is the approved engineering design for which
Morgan Engineering has prescribed the method of construction for the builder.
The dotted line here is denoted as being the vapour barrier. And this can be
evidence [sic] through the diagram and what is classed as the internal rib
section. And you’ll see there is a note there, the vapour barrier on 50 mil of sand
bedding. And it points to the dotted line which denotes the – the vapour barrier
installation. The reason why I’m pointing you to the internal rib section is
obviously that is part of the vapour barrier that is required to be installed below
the slab to the extent of the slab. And that dotted line is shown in the other
diagrams, or detailing – engineering detailing on either side of that. In that
instance, you’ll note that the vapour barrier on either side of that you’ve got the
widened edge rib section. It shows that same dotted line. It shows that dotted
line extending beyond that slab edge rebate. On the left-hand side the edge rib
section, again it denotes that same dotted line. And it shows that line extending
beyond the edge of the rebate.
So this – this provides that the engineer had required that that vapour barrier
extend under the whole of the slab itself, and that it terminated outside that
external edge of the slab and not inside the internal edge of that slab.
46 Transcript 2– 30, line 29.
47 Transcript 2-13, line 14.
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Ms Nean: And it doesn’t show the barrier terminating any specific distance up
the side of the – the – side of the slab?
Mr Noble: No. It doesn’t show it extending vertically whatsoever. It just – it
just denotes it as extending beyond the slab edge.
[88] The situation has arisen because of the particular use of a waffle pod slab. Extensive
regard has been had in the course of the hearing to the Australian Standard in relation
to the placing of membranes generally in slab construction.
[89] The Australian Standard addresses the traditional methods of foundation slab
construction by requiring a membrane to stop moisture moving into the slab. The
diagrams that are illustrated in the Australian Standard are predicated upon a
traditional in-ground footing. They show a membrane extending up to a finished
ground level, or an internal membrane that extends above the height of finished
ground level, which prevents moisture passing through the slab edge.
[90] The singular characteristic of a waffle pod slab is that it sits on top of the ground. The
builder has given evidence that the requirement was to only extend the Visqueen (the
plastic sheet which acts a membrane) to the edge of the bottom of the slab, as that is
the height at which it handed over the property in this instance, as no landscaping was
included in the contract.
[91] Mr Noble in his statement identified that the relevant Standards and Codes only
require that the vapour barrier extend to ground level:48
Neither AS 2870 nor the National Construction Code or the Building Code of
Australia prescribe an amount which the vapour barrier must extend past ground
level. The requirement is that the vapour barrier extend to ground level.
[92] Diagram (b) of AS 2870 (5.3.3.4) shows the internal membrane extending above the
‘finished ground including paving’.
[93] From the builder’s viewpoint, the ‘ground level’ which is referred to in AS 2870
(5.3.3.4) is the level of the bottom of the slab to which the surrounding ground was
scraped, and at which the building was handed over.
[94] To an owner, the ‘ground level’ may be thought by them to be the ultimate anticipated
level after the landscaping, which is the finished ground level shown in diagram (b)
of that Standard.
[95] In the absence of any requirement in the engineering design for the building, or any
provision as to landscaping in the contract, however, the ground level is the level of
the base of the slab in the case of a waffle pod construction, as was used in this
building.
[96] The builder and Mr Noble gave evidence that there are a number of edge treatment
methods that could be adopted if it was desired to subsequently pile soil against the
side of the slab, which would act to prevent moisture passing into the slab.
[97] I accept the evidence of Mr Noble which I have referred to in these Reasons.
48 Statement of Steven Noble, 11 July 2019, [14].
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[98] In the context of the engineer’s design and the Australian Standard and the Building
Code of Australia then, the builder has complied with the requirements as to
placement of an under slab membrane to the waffle pod construction.
[99] As I am not satisfied that the builder placed the fill against the side of the slab, and as
the builder did not contravene the engineer’s design for the slab, or the Australian
Standard, or the Building Code of Australia, as to extending the membrane up the
external edge of the waffle pod slab, then a basis to give a Direction to Rectify is not
made out.
The waffle pod system
[100] I consider that this matter has highlighted a significant issue of concern to consumers
in relation to the use of waffle pod construction.
[101] It is striking that the Australian Standards do not specifically deal with this very
common method of slab construction.
[102] I asked Mr Noble about Australian Standard AS 2870, as to whether there are any
specific references to waffle pod construction, and he advised there were not:49
Member: … Mr Noble, let’s get back to where we started, then. Let’s get back
to the Australian Standard AS 2870. You will find that at…?
Mr Noble:… Sure.
Member:… Red letter 49 of the – of your statement?
Mr Noble: Yeah. Okay. Sure.
Member: Now, for the discussion, there’s three typical diagrams there. In the
discussion we just had, does any of those relate to a waffle pod construction?
Mr Noble:… No. None of those do. The – the (b) of the deep edge rebate
alternative is – is what you’re talking about. That’s not a deep rebate alternative.
Member: Okay. So…?
Mr Noble: Because it’s not a rather large rebate, if you like, for which…
Member: So can you point to any provision of the Australian Standard or the
Building Code that refers to a required damp-proof membrane for a waffle pod
construction?
Mr Noble: No.
Member: And that might be our problem?
Mr Noble: The – I only point to the requirements for the termination of the
vapour membrane.
[103] Ms Beikoff said that the only instructions as to landscaping she received from the
builder was from the supervisor, who said to ensure that all landscaping sloped away
from the house, and not to cover the inspection outlets for the sewerage. That advice
did not warn of the need to place a waterproof membrane along the edge of the slab,
or to treat the edge of the slab, before placing soil against the edge of it.
49 Transcript 2-32, line 41.
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[104] The Queensland Building and Construction Commission has a duty under section 3(c)
of the Queensland Building and Construction Commission Act 1991 (Qld) to ‘provide
support, education and advice for those who undertake building work and consumers’.
[105] When a consumer buys a house, as a subsequent purchaser, which has a traditional
slab system, they can expect that the traditional practices of providing a waterproof
membrane are in place to prevent water moving into the edge of the slab from any
adjoining soil which is at the finished ground level.
[106] Once soil or gardens or turf is placed against the edge of a waffle pod slab, to the level
of the top of the edge of the slab, and is blended into the surrounding area, it cannot
be readily distinguished by a consumer from a traditional slab system, as it can no
longer be observed to be sitting above the ground.
[107] Therefore, when a consumer buys a house, as a subsequent purchaser, which has a
waffle pod slab system, and there is soil or gardens or turf in place against the full
height of the edge of the house slab, the consumer has no ready way of observing that
the slab has in fact been constructed with a waffle pod system, or whether a membrane
or treatment to prevent water entry has been placed along the edge of the slab or not.
I consider this to be a matter of risk and concern.
[108] I asked Mr Noble whether the situation is that a homeowner could be in the situation
of having no protection, in the design of a waffle pod slab, against the effect of soil
being placed against the unprotected edge of the slab, and water entering the slab, and
that this seems to be a trap in the waffle pod design. Mr Noble responded that
education for subcontractors and homeowners could be helpful in this regard:50
Education around this could be helpful for subcontractors undertaking work,
and education for homeowners could also be helpful. The commission does
endeavour to do this through various information documents we provide on our,
you know website, to try and assist in informing homeowners and also
contractors of their obligations. However, it’s not perfect.
[109] I asked Mr Noble if he was aware of any similar problems arising with other waffle
pod constructions, and he said that he was:51
I am. I have another matter, which is down the coast, another recent matter,
where fill material has been placed by a subcontractor against the – the slab to
the perimeter of – of this particular dwelling, and it was causing significant
moisture ingress. That was exacerbated by having a vinyl flooring system inside
the house, which prevented that evaporating through the slab, causing mildew
– so this is not uncommon, in my experience.
[110] I commented to Mr Noble that ‘You almost wonder why this doesn’t happen far more
often?’ and he responded that it occurs more often than people are aware of:52
I believe this has happened more often than people are aware of, through my
observations on construction.
[111] I consider this is a situation which the Queensland Building and Construction
Commission, in its consumer protection role, should investigate, and consider whether
50 Transcript 2-37, line 12.
51 Transcript 2-37, line 21.
52 Transcript 2-14, line 4.
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appropriate warnings should be provided to consumers, and whether the Australian
Standard and other regulatory provisions should be amended to address the situation.
Conclusion
[112] I have found that it has not been established that the builder placed fill against the
unprotected edge of the slab, and was not required by the Australian Standard, or other
regulatory provision, to do anything further in relation to the edge of the slab of a
waffle pod system, and therefore do not consider that a Direction to Rectify should be
issued to it.
[113] I confirm the decision of the QBCC made on 31 October 2018 to not issue a Direction
to Rectify to the builder.
[114] Having regard to the issues raised in this matter, I urge the Queensland Building and
Construction Commission, in its role as a consumer protection agency, to:
(a) investigate the prevalence of moisture problems arising in houses which have
been built using the waffle pod system; and
(b) give consideration to a need for builders of a new house with a waffle pod
system to warn their customers that they should not place soil against the side
of the slab without a waterproof membrane or edge treatment being provided;
and
(c) that there should be a way of a subsequent purchaser of a house being able to
readily determine what slab system has been used, and whether an appropriate
waterproofing system to the edge of the slab is in place if it is a waffle pod slab,
before purchasing the house; and
(d) give consideration to warning consumers who are the subsequent purchasers of
a house, of the risks of buying a house with a waffle pod slab if the edge of the
slab does not have a waterproof membrane, or treatment, between it and soil
placed against it; and
(e) consider whether the Australian Standard and the Building Code should be
amended to specifically refer to waffle pod slabs; and if so, to make appropriate
representations for amendment of the relevant Standard and Code to provide
clarity and direction as to the placing of a membrane along the external edge, or
for edge treatment, of a waffle pod slab.
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Official source: https://www.sclqld.org.au/caselaw/QCAT/2020/377