Browse Forums Building A New House Re: Vapour Barrier issues 5Jun 15, 2022 1:15 pm Lees I spent thousands of money with 5 times of private inspection The inspector says it’s up to me to fight with them the inspector only can give me report and decision is mine And when I ask builder to fix they just say their house has no problems just trust them not inspector How can I fix this? Should I hire someone to fix? Check your Engineering Details, Always get proper engineering/Construction advice during the stage completions Ideally a 2c drop off is preferable (Fig b & c), now you are stuck with a landscaping /paths problem and exposed Raft edge if the builders detail/ construction (Fig A) is correct ie 1c drop as they are saying, then you have wasted the inspection money as this should have been picked up before footing pour. Weep holes are best above the ground or path NCC Figure 3.2.2.3 OT Some builders don't care after handover that you are put in a worse position... as it becomes your problem to deal with Furthermore, why rake the soil over the weep holes as it has to be removed ? We had 1c Slab drops introduced years a go by a large project builder lol, skimping on concrete.... It was a disaster now min 2c (Fig c) Cheers Chris Designer,Engineer (Civil,Const & Envir),Builder,Concrete & Masonry Contract.Struct Repairs Re: Vapour Barrier issues 6Jun 15, 2022 1:55 pm THANK YOU SO MUCH FOR YOUR ADVICE! This is my first house lol So I was worried a lot and I don't know much about the building but the private inspector says the problem is big so I was scared You are right x I'm over thinking Re: Vapour Barrier issues 7Jun 15, 2022 1:59 pm Thank you for your comment! May I have more details about “why rake the soil over the weep holes as it has to be removed ? We had 1c Slab drops introduced years a go by a large project builder lol, skimping on concrete.... It was a disaster now min 2c (Fig c)” It's a bit hard to understand for me lol Re: Vapour Barrier issues 8Jun 15, 2022 2:13 pm Lees Thank you for your comment! May I have more details about “why rake the soil over the weep holes as it has to be removed ? That is a question for your building surveyor since you have paid him ask him for certified alternate solutions that include the paths, landscaping, etc. It's one thing saying its wrong, they must offer alternate fixes, otherwise what use is his report, the builder laughs it off. While get stuck wondering and doing nothing? Lees We had 1c Slab drops introduced years a go by a large project builder lol, skimping on concrete.... It was a disaster now min 2c (Fig c)” It's a bit hard to understand for me lol Engineers in WA turned on the builder and refused to certify his alternate 1c slab details The same builder had other failures, It's all about cheapening the build cost. nuf said Cheers Chris Designer,Engineer (Civil,Const & Envir),Builder,Concrete & Masonry Contract.Struct Repairs Re: Vapour Barrier issues 9Jun 15, 2022 3:05 pm Many thanks for your kindness after pre, post slab and frame inspection we did one more meeting on the site as our request didn't receive 😭 And our 4th inspection finally general manager said will accept our request but we didn't check it was properly fixed (our fault) and last week we did PCI and the same private inspectot said it was not fixed as picture So I complaint builder and the answer No further action, the membrane is fitted, the soil is covering it for the purpose of falling surface water away. The client will be installing concrete and the soil will certainly be removed. The private inspector says Without the required repairs to this vapour barrier, this installation is non-compliant with the Australian Standards and is susceptible to excessive moisture, which may create major secondary defects as the building ages. The builder must supply the vapour barrier system clean, visible and tight against the concrete perimeter slabs at handover, without compromise Re: Vapour Barrier issues 11Jun 15, 2022 3:17 pm Lees I didn't want to do paving but sounds like I must do If the builder builds properly should need to do paving as well? if youre on reactive soil, yes. Your picture indicates you are. https://www.bostongrp.com.au/documents/ ... -perfo.pdf Dark matter scientist, can breathe underwater, mind reader and can freeze matter just by willing it. Trust me, its in my sig. Re: Vapour Barrier issues 13Jun 15, 2022 5:48 pm Concrete Slab - Perimeter To All Areas Vapour Barrier System ( Polyethylene ) - Missing / Damaged / Not to Ground Level ( Overall Non-Compliant ) The DEFECTIVE ( Non-Compliant ) Vapour Barrier was also picked up at various other stage inspections. And now we are the the Final Report, the DEFECTIVE ( Non-Compliant ) Vapour Barrier STILL REMAINS AN OUTSTANDING ISSUE. ♦DEFECT 1 FOUND : ———————————— DAMAGED VAPOUR BARRIER-( polyethylene ) VARIOUS RIPPS, HOLES & DAMAGES TO THE PLASTIC, KNOWN AS THE POLYETHYLENE BARRIER. As per Residential slabs and footings - AS 2870—2011 (c) Resistance to puncture and moisture penetration—shall be determined using the CSIRO ‘Method for determination of the penetration resistance of water vapour barriers to falling aggregate’. Vapour permeance following this test shall not exceed 0.02 mg/N.s with no punctures or rips in the film. And As per the National Construction Code ( NCC ) Volume Two - Building Code of Australia ( BCA ) - 2019 - Page 113 A vapour barrier must be installed as follows— (i) lap not less than 200 mm at all joints; and (ii) tape or seal with a close fitting sleeve around all service penetrations; and (iii) fully seal where punctured (unless for service penetrations) with additional polyethylene film and tape. ♦REPAIRS REQUIRED - All the ripps and/or damaged area needs to be taped. DEFECT 2 FOUND : ————————————THE PLASTIC, KNOWN AS THE POLYETHYLENE BARRIER, IS NOT CONSISTENT WITH OVERLAPPING OF 200mm, TAPED. THERE ARE ARE OPEN AREAS, SPREAD THROUGHOUT THE PERIMETER OF THE CONCRETE SLAB. As per Residential slabs and footings - AS 2870—2011 (c) Resistance to puncture and moisture penetration—shall be determined using the CSIRO ‘Method for determination of the penetration resistance of water vapour barriers to falling aggregate’. Vapour permeance following this test shall not exceed 0.02 mg/N.s with no punctures or rips in the film. And As per the National Construction Code ( NCC ) Volume Two - Building Code of Australia ( BCA ) - 2019 - Page 113 A vapour barrier must be installed as follows— (i) lap not less than 200 mm at all joints; and (ii) tape or seal with a close fitting sleeve around all service penetrations; and (iii) fully seal where punctured (unless for service penetrations) with additional polyethylene film and tape. REPAIRS REQUIRED - All the open joins must have added plastic, known as polyethylene, with overlapping of 200mm and completely tapped up. DEFECT 3 FOUND : VAPOUR BARRIER-( polyethylene ), IS NOT UP TO THE FINISHED GROUND LEVEL. THE FINISHED GROUND LEVEL WILL BE THE CONCRETE, GARDEN, FINISHED SOIL, ETC, NOT THE DIRT EXPOSED AT PRESENT. As per the National Construction Code ( NCC ) Volume Two - Building Code of Australia ( BCA ) - 2019 - Page 113 (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. REPAIRS REQUIRED - Areas are not up to future ground and/or finished paving or concrete levels and must be extended with 200mm overlaps and taped to all joints in the the plastic. The polyethylene should be much higher then the ground and be cut nice and close ( adjacent) to the concrete perimeter slab. # ONCE ALL THE ABOVE REPAIRS HAVE BEEN COMPLETED. ————————————————————————————————The polyethylene vapour barrier from beneath the concrete floor slab must be turned up the external side faces of the concrete slab edge beams. Failing to install the vapour barrier correctly will allow moisture ingress via slab edge dampness into the internal timber wall skins and/or the floor coverings if not done. The polyethylene vapour barrier must properly extended up the external side faces of the edge beams to at least the height of future finished ground level or paving i.e. 75mm below the damp-proof course and bottoms of the weepholes, after which any termite barriers that are in place, if required, will also need to be properly instated. Without the required repairs to this vapour barrier, this installation is non-compliant with the Australian Standards and is susceptible to excessive moisture, which may create major secondary defects as the building ages. Rectification works are necessary as soon as possible to ensure all standards are met. ♦As per the National Construction Code ( NCC ) Volume Two - Building Code of Australia ( BCA ) - 2019 - Page 113 3.2.2.6 Vapour barriers 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— (a) Materials A vapour barrier must be— (i) 0.2 mm nominal thickness polyethylene film; and (ii) medium impact resistant, determined in accordance with criteria specified in clause 5.3.3.3 of AS 2870; and (iii) be branded continuously “AS 2870 Concrete underlay, 0.2 mm Medium impact resistance”. (b) Installation A vapour barrier must be installed as follows— (i) lap not less than 200 mm at all joints; and (ii) tape or seal with a close fitting sleeve around all service penetrations; and (iii) fully seal where punctured (unless for service penetrations) with additional polyethylene film and tape. (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 Re: Vapour Barrier issues 14Jun 15, 2022 5:49 pm REPAIR METHOD OF POLYETHYLENE ——————————————————————THE ONLY TRUE REPAIR METHOD IS TO ENTIRELY DIG THE EXTERNAL PERIMETER OF THE BUILDING AT LEAST 300mm below the vapour barrier system Polyethylene (plastic) damaged areas, which will vary in areas and then overlap the existing plastic with the new plastic by a minimum of 200mm and to tape all the overlaps of the Polyethylene (plastic). The overall height of the plastic must be above the top of the slab rebate surface for now at construction stage. The plastic must be hard against the concrete with no soil, rocks and/or builders debri in between the slab and the Polyethylene (plastic). Any over pour of concrete must be cut flush to the concrete rebate and include engineers report for alteration works and if steel mesh is visually seen, then the structural engineer must now also be notified to include the repair methods of the exposed steel mesh areas to determine the remedial works. Whilst this may now be a lot of work, there must not be any compromise in the quality finish as the slab is a structural component that must be protected as per the National Construction Code ( NCC ) Volume Two - Building Code of Australia ( BCA ) - 2019 - Page 113 OR LIQUID APPLIED WATERPROOFING COMPOUND ANOTHER OPTION OF REPAIR IS BY APPLYING A LIQUID APPLIED WATERPROOFING COMPOUND ( 2 COATS min )as per : AS 2870—2011 - Page 56, Figures 5.7 USE OF DAMP-PROOFING MEMBRANE FOR SLAB PROTECTION And also as per AS 2870—2011 - Page 148, Figure C5.7 USE OF DAMP-PROOFING MEMBRANE FOR SLAB PROTECTION. TO ENTIRELY DIG THE EXTERNAL PERIMETER OF THE BUILDING AT LEAST 300mm below the vapour barrier system Polyethylene (plastic) damaged areas, which will vary in areas and then apply a liquid damp-proofing membrane ( waterproofing ) to the face of the concrete slab, As per 5.5.2 Isolation of concrete from the ground, from Residential slabs and footings - AS 2870—2011 - Page 56, Figures 5.7 USE OF DAMP-PROOFING MEMBRANE FOR SLAB PROTECTION, The method of implementing the requirements of Clause 5.5.2 is as follows: • The floor level bench level should be chosen to be high enough that the ground surface adjacent the house can be graded away. • During concrete pour the edge of the concrete footing should be managed to minimize over-spill and groove formation under edge formwork. • After concrete pour and during construction in accordance with Clause 5.5.2(b) and details shown in Figure C5.7: • Remove and ‘tidy up’ overspill (as early as possible). • Tidy up and repair plastic membrane after boards stripped and ensure following trades protect plastic membrane. • Tidy up and repair plastic membrane as part of final clean up to leave plastic ready for paving. • Construct paving with protective 0.5 mm thick damp-proofing material layer placed vertically against edge of slab and lapped over slab damp-proofing membrane as shown in Figure C5.7; or in accordance with Clause 5.5.2(c)). • Alternatively after concrete pour and during construction in accordance with Clause 5.5.2(c) and details shown in Figure C5.7: • When formwork is stripped, apply a two coat (minimum dry film thickness of 0.35 mm) spray of a liquid applied waterproofing compound to the footing edge from top of slab level continuously down to the point of emergence of the under footing damp-proofing membrane. Ensure 75 mm overlap with the footing damp-proofing membrane. Ensure full coverage over all vertical edge concrete and any horizontal overpoured concrete. • Before spraying ensure— • if gutter depression longer than 2 m is left in concrete after boards are stripped, chip a drain outlet; and • Before spraying ensure— • if gutter depression longer than 2 m is left in concrete after boards are stripped, chip a drain outlet; and • thoroughly clean and blow away any loose material from around footing before spraying. • Protect the waterproof coating during construction. ♦The detailed repair options ABOVE is as per the standards of Construction Code ( NCC ) Volume Two - Building Code of Australia ( BCA ) - 2019 - Page 113 and/or ANOTHER OPTION OF REPAIR IS BY APPLYING A LIQUID APPLIED WATERPROOFING COMPOUND ( 2 COATS min )as per AS 2870—2011 - Page 56, Figures 5.7 USE OF DAMP-PROOFING MEMBRANE FOR SLAB PROTECTION And also as per AS 2870—2011 - Page 148, Figure C5.7 USE OF DAMP-PROOFING MEMBRANE FOR SLAB PROTECTION. HOWEVER, we highly recommend a NEUTRAL or INDEPENDENT ENGINEER, also assist in this matter. ♦AS 2870—2011 - Page 56, Figures 5.7 USE OF DAMP-PROOFING MEMBRANE FOR SLAB PROTECTION, 5.5.2 Isolation of concrete from the ground The concrete member shall be isolated from the aggressive soil or groundwater by a damp-proofing membrane in accordance with Clause 5.3.3, installed and terminated in accordance with one of the following: (a) Terminated at or below finished ground or paving level as shown in Figure 5.7. (b) Installed and terminated at finished ground or paving level and lapped with a suitable 0.5 mm thick damp-proofing material complying with AS/NZS 2904 and lapped a minimum of 75 mm vertically or horizontally in accordance with Figure 5.7. The damp-proofing material shall extend up to the finished ground or paving level, and be sealed around all penetrations by pipes or plumbing fittings. NOTE: A suitable 0.5 mm thick damp-proofing material may be embossed black polythene f ilm of high impact resistance of 0.5 mm thickness prior to embossing and meeting the requirements of AS/NZS 2904. (c) Installed and terminated at below finished ground or paving level and lapped a minimum 75 mm with a suitable liquid-applied waterproofing compound applied to the face of the concrete. The liquid-applied waterproofing compound shall extend up to the finished ground or paving level and be sealed around all penetrations by pipes or plumbing fittings (see Figure 5.7). NOTE: A damp-proofing material may be used in addition to the liquid-applied coating during construction to avoid damage to the coating. Where the damp-proofing membrane is damaged during installation, or the finished ground or paving level is altered, the provisions of either Item (b) or (c) shall be complied with. Where a damp-proofing membrane is installed, a layer of bedding sand shall be provided under the slab panels. Where this layer is deeper than 100 mm, it shall comply with Clause 6.4.2. END RESULT THAT MUST BE ACHIEVED ——————————————————————The builder must supply the vapour barrier system clean, visible and tight against the concrete perimeter slabs at handover, without compromise Re: Vapour Barrier issues 15Jun 15, 2022 6:02 pm MrSober Is concreting around the perimeter of the house the only option in this case? Not because of the vapour barrier, but because of the soil type and managing slab heave risk. Dark matter scientist, can breathe underwater, mind reader and can freeze matter just by willing it. Trust me, its in my sig. Re: Vapour Barrier issues 16Jun 16, 2022 1:39 pm [The vapor barrier will not protect the house from moisture getting under the slab, only from contact with the slab, and generally only from underneath given that these barriers arent someway fixed to the side of the slab.] Sorry to bother you x Is it because the builder didn't install properly or normally vapour barrier is not protecting the house from moisture? Re: Vapour Barrier issues 17Jun 16, 2022 1:58 pm Noname MrSober Is concreting around the perimeter of the house the only option in this case? Not because of the vapour barrier, but because of the soil type and managing slab heave risk. Ah okay, as I think I have similar soil type being H or M but can't seem to find where I had that information at the moment. I just wonder if there is something else that can be done to have a similar solution as I don't visually want concrete around the whole house. Re: Vapour Barrier issues 18Jun 16, 2022 3:57 pm Lees [The vapor barrier will not protect the house from moisture getting under the slab, only from contact with the slab, and generally only from underneath given that these barriers arent someway fixed to the side of the slab.] Sorry to bother you x Is it because the builder didn't install properly or normally vapour barrier is not protecting the house from moisture? you clearly didn't read the link i posted for you. There are two separate things here. Rising damp The purpose of the vapor barrier is to protect the concrete slab from being exposed to moisture, which overtime has a propensity to rise up through concrete and start affecting your frame, walls etc. This is called rising damp. This can cause things like mould to grow etc. Slab heave The purpose of the concrete perimeter paving is to stop water from pooling against your slab and getting under it. In reactive soils can cause them to swell and lift your home causing slab heave. . Neither of these scenarios is good. The solutions are separate. However, placing a concrete perimeter path protects against both. If there is paving, the water/moisture won’t be able to get to the edge beams. Given you are on clay (I can tell from the pics and the fact that the builder has added earth sloping away from your foundations during the build), you should be installing a concrete path after hand over. If you don’t install this path, you can expect the builder to point to your failure to do so if issues of house cracking an movement occur. Given you are on clay, it is highly likely you WILL experience these without some sort of path. The path is your first step to protect against damage to your house and protecting yourself from the builder claiming it’s your fault for poor slab maintenance. Trust me, they will always blame you first. You need to think about this logically – if the builder fixes this plastic sheet by doing as the inspector suggests, it doesn’t protect your house from the damage that the sheet is meant to UNLESS you maintain it – ie ensuring there is no way for water to end up between the sheet and the house. Are you going to be out there making sure its affixed to the edge beams? Making sure there is nothing between it and the concrete and to ensure no water can get between it? No. You’d probably end up putting a bloody garden bed over it, forgetting about it and putting water there yourself, completely invalidating the purpose of it in the first place. The fact that the builder may not have installed the barrier properly all the way up the edge beams is not great but on the balance of things its one of those things that’s not overly worth arguing about. Save your energy. You need to install a perimiterto protect your home, and by virtue of doing so, you’re solving this issue. Dark matter scientist, can breathe underwater, mind reader and can freeze matter just by willing it. Trust me, its in my sig. Re: Vapour Barrier issues 19Jun 16, 2022 4:12 pm MrSober Noname MrSober Is concreting around the perimeter of the house the only option in this case? Not because of the vapour barrier, but because of the soil type and managing slab heave risk. Ah okay, as I think I have similar soil type being H or M but can't seem to find where I had that information at the moment. I just wonder if there is something else that can be done to have a similar solution as I don't visually want concrete around the whole house. it needs to be an impermeable barrier. Concrete is simple to do and you have lots of options in that space (exposed aggregate of varied colours, stamped, coloured, stenciled etc.). You could lay paving over the concrete for an upmarket look, whatever. The key is to direct water away from your house. Besides, having a path around your house is useful for so many reasons Whether you do or don't is your prerogative, but expect movement if you don't, and expect to have the builder blame you for not maintaining requirements to maintain your warranty for any work that related to movement or cracking in your house. Dark matter scientist, can breathe underwater, mind reader and can freeze matter just by willing it. Trust me, its in my sig. Re: Vapour Barrier issues 20Jun 16, 2022 4:14 pm to the people in this thread, i would highly recommend you search this forum for "slab heave" and educate yourselves on what's occurred to a number of forum members here and teh heartache its caused. Dark matter scientist, can breathe underwater, mind reader and can freeze matter just by willing it. Trust me, its in my sig. Hi, I had a barrier reef pool installed less that 2 years ago and the gel coat is already fading. The colour is electric grey shimmer which isn’t available… 0 3805 I’m not a structural engineer but I’m free. you still need an engineer for the plans. I only have part of your plans, but you seem to have a 850mm drop from the side… 3 9944 DIY, Home Maintenance & Repair Hi, I have an old fence/barrier made of treated pine logs bolted to plates and these are bolted to very large metal posts/girders. The plates and bolts are rusted through… 0 15111 |