(DPM) with joints well lapped and folded. . A poorly compacted, damaged or weak screed should be completely removed by mechanical means and reinstalled correctly. . However, when I hammer-fix the battens to the concrete I'm going to punch holes in my DPM. do I still need a DPM under that insulation? it is internal and sitting on a structural slab that is wrapped in DPM externally. If you are using a final floor finish which will be fixed to the screed’s surface using an adhesive then you will need to lightly sand the laitance off the surface of the screed before using a compatible primer and adhesive. Use screed on top of a concrete base to give your floor a level and smooth finish. Other benefits. I will be tiling over the screed so looking for the simplest option. Can be used over underfloor heating. Water under tiles. Instead of a membrane, use a foam underlayment material which will keep the wood from touching the screed directly (avoiding any moisture transfer) but which will also allow the screed to breathe and thus dry over time. Just lay a couple of good thick beads on the dpm and stick it to the wall. Diagram B39 - Proper sealing. Ask the mods to move your thread to Flooring forum and see: dazlight Fri 29 aug 2020 for a specific response to a difficult surface. Our costs are ballpark averages – get a local tradesperson to quote now. The 40mm between the joists is about 0. The installation of the DPM is extremely important as this acts as a barrier to prevent damp rising up through the substrate, from the ground below. Which way would you go, 1000 gauge plastic under slab OR liquid dpm between slab and screed? renovateduk, Jul 17, 2009 #3. Location. Guidance on how to install insulation between a floor screed with Kingspan Kooltherm K103 Floorboard. 1 Feb 2010. 5kN/m2. The surface should be of sufficient quality and. However the tiler should apply a Primer before screeding such as StopGap P141. So, as money's too tight to mention round here, I replaced the leaking door with a cheap UPVc one. if your DPM were above the concrete, the uFH would be heating a large damp lump of concrete. Our Epoxy DPM can be used on concrete floors and fine concrete screeds, of not less than 50mm thick in the case of un-bonded screeds. ) chrysotile (white) asbestos fibres. Answered 22nd Aug 2016. 12) Tiles glued. Reaction score. The basic screed construction for under floor heating systems generally follows the ‘floating’ screed construction, where a Damp Proof Membrane (DPM) and tacker insulation panels are laid over the. 25W/m 2 K to meet with building regulations, even if you didn’t plan to. The floor originally had a carpet laid on top of the tiles, when I lifted it nothing felt, looked or smelled damp. The blockwork above the DPC will become saturated and cause damp problems within the extension, the skirting boards will rot and the mould will occur on the plaster. The polyethene slip membrane installed over the insulation must be overlapped and sealed to prevent loss of screed. A few months have passed since then and is now on average 2. Screed & Insulation. Wet underfloor heating installation cost. A hydronic setup is connected to your central heating system, powered by a boiler or some form of renewable tech (eg a heat pump). so FBall seems the way to go). The purpose of DPM. The polythene damp proof membrane (DPM) – generally a 1200 gauge- can now be rolled out into place ensuring the perimeter abutments are adequately covered. #Screeding #Sc. Damp Proof Membrane is intended for use within solid concrete floors to prevent the rise of moisture or damp through structure flooring. The Epoxy DPM 5kg is supplied in two 2. Because we were laying Karndean Flooring to a new extension we needed to check the % RH(relative humidity) of the concrete with a hygrometer. You also should have removed the vinyl tiles before priming and screeding. Insulation would be a good idea, but it also may not be a bad idea to knock the whole thing down and start again if the walls are only 4", the floor is rough, and the roof probably leaks too. "Turn off electricity and gas only if it’s safe to do so," he said. DPM's must be carefully protected where folded up the perimeter walls, and lapped under the DPC particularly at door openings. Scaffold boards should be used for barrowing and tipping concrete and screed and a light mesh of chicken wire can be used over separating layers or dpms over insulation under screeds as added. Then once the screed is dry use a liquid DPM such as F-Ball Stopgap F77. This process is not 100% foolproof and so during screeding an extra pair of hands is useful to tuck the materials together until the weight of the. 5mm Polyflor . 00 per roll. #5. Then a primer like the one you have at 4-1 then if needed another coat at 2-1. Get it level then when it is dry and can screw through floor board into blocks. The DPM (Damp Proof Membrane) is laid under the insulation on top of a soft blinding to ensure it is not punctured. For unbonded and floating screeds, a DPM may be specified between the base slab and the screed. Reinforcing concrete. Your builder or yourself should have laid dpm under the dpc course on top of the hardcore Base laid on soft building sand . i'm you have gathered by now, you havn't left enough depth to do this. The tiler can then latex or screed over the DPM. Like a lot of houses of that age, the ground floor is bitumen/asphalt over a concrete screed. Alan Jackson - Commercial Manager UK and Ireland - Gypsol. Thin screed to level old concrete floor. Suitable for most construction damp proofing requirements. The surface should be of sufficient quality and. In any case, it’s best to use a specialist to avoid damaging the floorboards themselves. Is it possibly to lay a new insulated floor without a concrete slab, using only floor screed? For example: Level layer of hardcore; Layer of sand blinding; Damp proof membrane. In terms of where the insulation should be placed, it can either be placed under the slab or between the. someone suggested removing the blocks on the inside along the width of the bifold and screeding all the way to the brick course. #3. #2. The main issue you need to remember about the DPC at the external walls is to have an upstand on the inner leaf and slope down to the other leaf. If you noticed the buildup wording is different to the detail drawing, it clearly shows dpm on top of concrete. POLYTHENE DPM & VAPOUR BARRIERS. Which is supposed to be a DPM equivalent. Where screed is laid on top of insulation, screed should have a minimum depth of 65mm. rev 2023. Beam and block floors may need a levelling screed or grouting to ensure base level. An ARDEX Damp Proof Membrane will protect the floorcovering. Perhaps you could paint a liquid DPM band all the way around the bottom, or flash band skirt, stapled on to the framework, tucked under the cladding. Give it a good wipe with a damp cloth and let it dry before you start. Reinforcement is required when you’re concreting areas that will be subjected to heavy loads, such as garages and car parks. Installation systems for tiling and natural stone. The current pipes to it will be diverted to another drain to the left of the photo. Our Liquid DPM can be used on walls under a render to create a flexible waterproof layer. No this is designed to be used under floor screeds, tiles, render or plaster. Alternatively, a mechanical key for the subsequent application of levelling materials such as a screed can be created by sprinkling fine washed sharp sand or kiln dried graded quartzFintan has travelled to Baden Württemberg in Germany to study passive housing and sustainable energy technology, gaining significant knowledge regarding the use of natural insulations in timber frame and solid wall constructions. To avoid damage to the insulation layer and the dpm it is necessary to take care in tipping, spreading and compacting wet concrete or screed. Care must be taken to a) ensure there are no holes or tears in the sheet that could allow. 27 Dec 2020. At the time of building the extension, due to new footings for structural walls to hold steels, drainage installed and the existing floor within the house showing signs of damp where the bitumen DPM had failed under floorboards nailed to the screed, I took the decision to remove all the floors, and oversited the whole house. Manchester • Member since 5 Jun 2015 • 64 jobs, 95% positive feedback. I was with Mapei last week inspecting a failed DPM that had been laid on a subfloor with no DPM under it. A water based is more likely the screed itself will blow as it cant take moisture at all, so it would be the 1st thing to blow. LKAB Minerals +44 (0) 7966 651006. 3. A traditional sand and cement screed is normally a 1:4 or a 1:3. Insulation sheets should be laid tightly together with the joints staggered to avoid movement. For bonded screeds, M-Bond Extra epoxy resin combinedWhen laying self-levelling screed, the thickness varies from product to product, however as a general guideline please find the depths below: Minimum depths are usually 2-3mm, however there are some products that can go down to “featheredge”. Trusted Trader, said safety must be a priority after a flood. The old floor tiles do contain a small amount of asbestos ( Marley tiles etc. Used the primer neat as guidelines suggested. Damp proof membranes (DPMs) can be used to help resolve damp issues which already exist or to avoid damp or moisture problems in the future. Water is added to ensure a thorough mix and to aid workability. Labour costs. If the applied DPM is still very tacky, this1. A Damp Proof Membrane or DPM is a waterproof barrier that’s introduced between your sub floor and your wood floor. This will allow the screed to bond to the dpm. #1. I am assuming its asphalt with a bitumen top layer, 10-15mm thick. DPM’s can be applied to either a suitable blinding layer under the slab or internally to the top of the slab. SikaBond® Rapid DPM is a single part moisture curing polyurethane. J. 5mt x 4mt rolls | £ 56. 74 inc. Warm construction build-up would be: - Sand blinded sub-base. m10 cement based levelling and wearing screeds 160 m12 resin flooring 163 m13 calcium sulfate based screeds 165 m20a plastered coatings 166 m20b rendered and roughcast coatings 169 m21 insulation with rendered finish 172 m40 stone, quarry and ceramic tiling or mosaic 173 m42 wood block composition block and mosaic parquet flooring 1763. Onto the concrete. Hence we always say DONT apply a surface dpm to a subfloor subject to rising damp. £14 per m2. Our team of highly experienced technical experts are always on hand to provide the highest level of support and advice to our customers. Guidance on how to install insulation between a floor screed with Kingspan Kooltherm K103 Floorboard. Definition of terms See full list on ecotileflooring. DPM is usually below the concrete, then the insulation, then a polythene sheet to stop the insulation floating as the screed is poured. It stops around 10mm away from the internal walls in all rooms. If the coating is not going to be the final decorative surface and. then ducting should be provided to allow air through the solid floor and into the void under the existing house. VCLs prevent excess moisture entering a wall’s cavity, behind the insulation. Solid floor insulation –screed finish: Per m 2: £70: £90: £80: Labour: Per day: £180: £250: £215:. The same larger hole after I cut back some of the sandy concrete. Hi, I have an area of approx 6m by 3m on a ground floor extension which is block and beam construction, that I now need to insulate and screed to finished floor height. Then use the correct screed. Cushion Ultra Silver Wood 10m² Underlay: The best laminate underlay for damp protection. Kitchen floor, underfloor heating, screed and DPM. 1 or just a bit less. This will give calculated u-value of 0. Also checking, the dpm is meant to be underneath the insulation? Two options: - Jablite Jabfloor 70 100mm (or jabfloor 100 or 150 grade but not sure what the difference is, building merchant sells the 70) - Xthratherm/Kingspan 100mm. If in the screed then no problem with this. . blocking/nogging for support of plasterboard 43mm x 38mm. UZIN has the right floor damp proof membranes for damp proofing floors. Guarantees the early laying of all floorcoverings. To ensure a level finish to the floor, a layer of screed is added over the top of the concrete, which consists of sand and cement. A DPM should be impermeable to water in liquid or vapour form and should be tough enough to withstand possible damage during laying of screeds, concretes or floor finishes. This allows for the full 5kg or just half to be mixed at once depending on the area to be covered. Your privacy. 13) Polypropylene. • Unbonded (i. I would also gripfill under the plate to supplement the fixings if it were screed. The advantages are the relatively low price of about £12 per square metre in combination with also relatively low installation costs of £8 – £12 per sqm as well as the high load- bearing capacity of cement screed. In the attached photo I have removed poorly laid DPM and insulation boards with a view to starting again. Vac up any loose sand once it's set and then tile. It is good practice to either fit another DPM or tape the insulation joints, when adding a screed on top of inso'. It has had an extension about 50 years ago and that is the problem room as the flooring was laid without any DPM under the existing concrete floor, so there are some rising damp issues (I think). 2. I've dug down and exposed part of the DPM sheet under the slab so I'm happy using trade plan, turbo then renovation screed. below this liquid screed I am adding 50mm EPS100 to build up the depth (which reduces the thickness of the screed) and also to fix the UFH pipes to. Fit a damp proof membrane as above, then lay a separation layer. They can therefore be laid under the DPM (the DPM is still necessary to prevent. The subfloor. Drybase Liquid-Applied DPM should be used in situations where the final surface is going to be covered. It may be applied onto either a solid in-situ concrete ground floor slab or onto a precast concrete floor unit. Ideal for use where there is no functioning structural DPM (common in older properties). I was planning on putting 1200g DPM down, then 80mm celotex insulation (taped at joints), then 65mm screed (approx 1. That about sums it up, but if your DPM is also serving as a radon barrier (even in a low risk area) the DPM should lap across the cavity (with a downstand) to seal the cavity from radon. California Country. . 5m2 at 1mm thickness 1. Prime and reapply , then screed to level and tile. At the moment, there is a dpm under the patio door overlapping the cavity and meeting the main dpc which comes up from the slab and wraps around the inner bricks. DPM over a new underfloor heated screed, the heating system must be turned off 48 hours before application. 100mm thick (can be heated) - Levelling screed (as required: self levelling compound, sand/cement screed etc) - Flooring, e. Whilst looking at the overall prices of each piece of work there's a couple of questions that have come up. This was due to a neighbour redirecting the water from his gutters. We converted our garage and building control are insisting I install a DPM over the screed (even though the DPM runs under the concrete raft foundation of the house). Top. Non-structural floor screeds shall be adequate for the location and intended use, and provide a suitable background for floor finishes. I thought common practice was to tuck the DPM under the DPC, but mine is the other way around: I'm about to start taping the insulation around the studwork and then I'm going. hours for Ceramics. The guidelines state that a damp proof membrane that is placed under the flooring should be around 1200 gauge and constructed of polyethene. Visqueen are recommending we don't use Ecomembrane but instead use Visqueen Vapour Barrier if we have a DPM under a screed with UFH heating, because it doesn't have folds in it and this helps prevent cracks in the screed. If its not right. 5kg multi chamber bags. Mobile Sales: 07920 715745. Based on a screed done in 1963 I’d say 95% there won’t be a effective damp proof membrane under it so a epoxy dpm should of been used like Ardex DPM1c. . Side extension refurb: old concrete slab is uneven with a line of about 10mm difference in heights down middle, and dpm under screed is visibly not 100%, with a few gaps. The idea is that you are to prevent any screed material from falling down any joints and coming into contact with the cold slab. Ideal for use where there is no functioning structural DPM (common in older properties). Step 3: Lay the watertight membrane. Mastic Asphalt – this is the earliest form of liquid DPM and is usually laid on the top of another membrane or a fibreglass surface. Lay and level the concrete slab, allowing sufficient time to dry out, as per BS 8203. AN INTRODUCTION TO. The screed manufacturer agrees that their screed can receive an epoxy DPM. Perfect for new builds and refurbishment projects, our range of floor insulation products include optimum peformance OPTIM-R Vacuum Insulation Panels (VIPs) with an insulating performance up to five times better than commonly used insulation materials, and. sandwiched under the screed, were also common and usually in liquid form, e. the screeder I use sets up a laser level and sets out his screed to that, the finish is always really good, much better than using long levels to transfer from section to section. I'm not saying this is the best thing to use. Maybe better to use a fibre based leveling compound instead, like Granfix Fibreflex 50 or similar. Vac up any loose sand once it's set and then tile. A section of the old screed layer has broken up around the edge of the patio door threshold. He intended to stick the floor to the bitumen DPM. is that do-able? if so, can I just run the DPM 1 course above DPC? it's too late to tuck. the cut. Unless there is an easy way. Hi, I'm doing a kitchen modernisation in my ex-Council house which was built in 1947. Air bricks are. DPM’s must be carefully protected where folded up the perimeter walls, and lapped under the DPC particularly at door openings. The rest of the floor will be as follows (top down); flooring. There is a concrete slab in place with a DPM underneath. This can include timber floors, tiles, laminate flooring and carpet. Country. 2m3). Guide Underfloor heating A guide for house builders NF71 NHBC Guide to Underfloor Heating 2nd draft RH. #1. 1200g DPM will be fine. The liquid membrane forms a strong seal and makes a permeable layer to enable moisture to evaporate off. BS8203 recommends a maximum of 75% RH prior to the installation of sensitive finishes. Consideration should be given to applying the DPM to the top of the slab, as the installation and moisture sensitive internal finishes are then protected from any residual moisture in the concrete. Don't think it will make much difference tbh, if you go the timber route use 22mm plywood instead of chipboard though. Looking for best method to both level and damp proof the concrete, to then be covered with a thin layer of celotex, then engineered wood. AFAIK - PIR insulation boards need have a DPM under them to protect the board. If there is an operational DPM beneath the concrete you don't need one on top. High quality painting, plastering and drywalling tools. UFH inside plastic polypanels 75mm screed (probably not liquid). 5sqm has blown. C. My work will be (in order of layers): 1) DPM 1000 gauge with joints taped with Polythene joint tape. com. 24 Jul 2009. The buildup is. 4m x 50m x 500g (200sqm) Black Polythene Vapour Control layer 4m x 25m (100sqm) TPS. Once set, you can then apply your screed flooring to the DPM base. CSC screeding was very efficient that they screeded our floor in under 4 hours (around 91sqm) with the help of the Mixamate. An ARDEX Damp Proof Membrane will protect the floorcovering. The current recommendations for an effective damp proof membrane are that the ground should be constructed using screed with the damp proof membrane laid either on top or below that layer. Use polyethylene sheeting to create a waterproof membrane to ensure that there is no leakage of the screed when it is pumped in wet. Unfortunately soon after it was laid it started crumbling and holes were appearing in places, as electricians and plasters came in to do their work and walked all over it, they did put black sns plastic sheeting down to protect it though. indd 2 08/08/2016 16:50:21DPM underneath and a plastic sheet on top to stop the screed getting between the insulation panels. ; Stiffness: Concrete floors generally possesses adequate prudery & does not parry under the applied load which result in generating problems in non-structural elements, e. 15) DPM under screed. If you're laying Karndean over existing flooring, be sure it is properly prepared. The specific liquid DPM system will depend on the type of substrate or screed. Consideration should be given to applying the DPM to the top of the slab, as the installation and moisture sensitive internal finishes are then protected from any residual moisture in the concrete. The main drawback. I am happy to employ gs guy to do pipe and install boiler but don't want to be calling the guy several times months appart, hence the attempt to make. Brian shows how to correctly fit a Damp Proof Membrain - DPM in a new build houseLink to the T-Rex tape Website Http://bodgeitwithbri. This allows for the full 5kg or just half to be mixed at once depending on the area to be covered. Mine is below the concrete. I am happy to employ gs guy to do pipe and install boiler but don't want to be calling the guy several times months appart, hence the. 11 Protection against heat, and BS 8204 Part 1 2003, Section 6. . The maximum depth you would use a smoothing compound would generally be around out 10mm, you can add aggregates, to bulk up the screed going up to 30, 40, 50+mm. They can feel wobbly when you walk on them but you get to the point when you can't get them any better and each give you walk on them or lift them you end up going around in circles. The vinyl that was laid bubbled up, so contractor removed it. Depends where the UFH pipes are. Staffordshire. It's a small garden room with a 2 course brink plinth, DPC, and then timber sole. 22) Steel. 75m2 at 3mm, 1. Hi guys. 4. Renovation of more than 25 per cent of a solid or suspended floor involving the replacement of screed or a timber floor deck would have to meet the standards required by the building regulations Approved Documents. Flexible - easy to detail and install on site. DPM’s can be applied to either a suitable blinding layer under the slab or internally to the top of the slab. Walkable in 6 hours. jeds. It's a complete lack of knowledge on your floorlayers part or possibly just a carpet fitter trying his luck. Magnesite must be completely removed. 4 Screed. For bonded screeds,4 weeks will depend on the depth - keep the screed as thin as possible - with wet UFH normally 50mm - any more will delay the drying time. Celotex PIR’s closed-cell, moisture-resistant composition helps to prevent water ingress. Moisture in the base will impede the drying of the screed. At the junction of wall and floor the membrane overlaps the damp-proof course in the wall. The bitumen is about 20 mm thick and, I believe, serves as moisture barrier as well as an 'appearance' finish. Dig the oversite ground to whatever height allows your hardcore, insulation, blinding, slab,screed. I see some under the wood bearers, so hopefully this will keep the base dry. The builder wants to apply a DPM to the top of the slab before it is dry. Walkable in 6 hours. co. We provide a range of solutions including DPM screed, flooring primers and more! We are also radon barrier suppliers, making us perfect for all your needs! Call: 0330 223 2364 ; Email: estimating@cscscreeding. 100mm **concrete base*. insulation 60mm. 55mm of TS15 will impart around 1. "Your insurance company should be able to instruct property drying. above the slab I am having a screed to cover the UFH pipes. On a job that’s had anhydrite screed pumped in, using a Wolff gm200 moisture meter readings in parts are 99. Screeds are covered by BS 8204, Screeds, bases and in-situ floorings, (2004). Temporary protectionI had part of a 9" wall knocked down for a doorway. The DPM is tied into the internal leaf of masonry. 5 ratio of cement to sharp sand. LKAB Minerals +44 (0) 7966 651006. Am hoping for UFH in screed (supplied won't do 50mm, only 65mm). 300 dries very hard Bitumen is soft so not compatible. But others are direct to earth, brick, rubble what ever. Below Floor Screed 1. I intend to lay 75mm PIR. The installation of a liquid damp proof membrane is a vital stage in the construction process, for both new builds and refurbishment work where a structural DPM may be missing or damaged, or where residual construction moisture is present in the floor. Proposed floor is pitch pine boards secret-nailed to 2 x 2 inch battens with insulation between, onto a concrete floor not known to have a DPM under it; therefore, DPM to go under the battens. Can be used as a Damp Proof Membrane on sub-floors not under hydrostatic pressure. If the insulation is going below the slab, the damp proof membrane (DPM) is laid next, followed by the insulation, a polythene separating layer, and the concrete slab. The insulation should not be stepped as this can act as an anchor point and cause cracking in bridging or on the screed under movement and cause weak spots in a void underneath. Complies with BS 8485:2015 + A1:2019 - industry standard for methane and carbon dioxide protection. Visqueen ECO Membrane Data Sheet. Buy Now. concrete slab. Using pin m/m's on a concrete or s&c screed floor needs experience - more important is what is the composition of the slab or the in-situ screed and if there is an actual DPM below the floor. The DPM (Damp Proof Membrane) is laid under the insulation on top of a soft blinding to ensure it is not punctured. PermaSEAL Liquid DPM can also be applied to concrete floors below screeds. uk ;. The company keeps abreast of market developments by. I would lay the DPM straight onto the existing and screed over. DPM sheets should be overlapped by at least 300mm. 5kg multi chamber bags. Pumped anhydrite floor screeds are not much dearer than ready-mix sand/cement, costing around £25/m3 (laid. Developed to suppress residual construction moisture in cementitious subfloors including power floated concrete and sand/cement screeds. Therfore putting foil faced boards under screed is a waste of time and is the principle reason kingspan make tissue faced boards. Our Liquid DPM can be used on walls under a render to create a flexible waterproof layer. Warm water systems, such as those available at The Underfloor Heating Store, feature an array of pipes, laid just below the surface of your floor. heating installations with cementious screeds provided a temperature of 27°C is not exceeded. Floor under carpet marked with chalk for wet areas. They can be used under resin screed finishes and are applied in thinner sections than standard cement screeds. Through DPM of course so a bit of silicone down the screw hole to seal the hole. It also looks like there could be polystyrene under the screed, this will be a barrier to damp coming from the ground. The membrane is manufactured in standard 125mu, 250mu, and 300mu thickness and in roll sizes of 1. Would that require two layers of DPM? For example: Level layer of hardcore; Layer of sand blinding; DPM; Concrete slab at a thickness of 3" inches; DPM (?) Jablite 70 floor insulation (75/100mm thickness) Vapour control layer ; Screed (1. This generally takes 1-2 days, depending on the thickness of the floor screed. Hi, I’m after some advice/suggestions regarding my floor…We’ve recently moved into a 60s house which has a screed floor, on top of a concrete base with no DPM. The oversized DPM was instead lapped with the DPM that was placed under the screed. 034 W/mK, and is used to insulate inverted roofs, basements, car park decks, and heavy-duty commercial, industrial and cold store flooring. LAY DAMP PROOF MEMBRANE. you might just have a low spot along the old wall where the concrete meets the wooden floor. A damp proof membrane (DPM) is used to create a barrier between a concrete (or screed) subfloor and the floor covering that is laid on top such as wood, ceramic or quartz tiles, laminate or carpet. 3. Then once the screed is dry use a liquid DPM such as F-Ball Stopgap F77. ), then 500 gauge plastic (or just use the leftover 1200 gauge DPM) then 100mm concrete slab. The. T ·Öà 4 ·Öò 8 ·Ñ• 2, Jun 15, 2007. Renovation property: £60 to £85 per square metre. • To provide a wearing surface. from a purely technical point of view a screed should always be divorced from the substrate by means of an operational DPM. Ground-bearing concrete floor slabs should be protected against ground moisture by providing a continuous damp proof membrane (DPM). A full sheet DPM is 250 microns (1000 gauge) thickness or above. The problem is by the time we insulate, screed and lay the flooring we will be above the dpc& membrane level by 4 inches. My DPM was these tiles that were bitumnned/black jacked to the floor. 24 h After curing of screedSANS 10400, Part J Floors (which is the SABS “deemed to satisfy” regs) states: “Ventilation of the subfloor space in suspended ground floors shall be provided by means of openings spaced not more than 2,4. It's joining onto the garage I'm converting so the whole floor is getting built up with polythene DPM,. Hello, I have noticed some funny things going on under the floor of our recently bought house, which was originally built in 1905. At its deepest it’s 150mm, what I’m stuck with is the builders trying to push on with the job. 10) Timber block between U channel and Cavity Weep Holes 11) Galzing unit (window/glass) 12) Tiles glued 13) Polypropylene 14) Screed 15) DPM under screed 16) Concrete slab 300mm 17) DPM under. The Epoxy DPM 5kg is supplied in two 2. It is important to ensure that a proper seal is achieved around all services. When we stick any floor down to the sub floor, solid or engineered, we insist on installing a liquid DPM unless the existing is guaranteed to be 100% in tact. 20m2, 50mm = 0. 150mm PIR insulation. Tape is a non starter. You will need to tear the lot up. Small hole dug through 2" soft sandy concrete to reveal hardcore and soil. Unbonded screeds are used either to install a damp proof membrane (dpm) between the base slab and the screed or where the base slab surface is unsuitable for a bonded screed due to problems such. The screed has water anyway, so a bit of ingress isnt an issue. Do you need DPM under garage floor? Solid floor The existing concrete floor can be used as a base, however a new damp proof membrane (DPM). doors. The 'vapour barrier' attached to your underlay will only protect your floor from a slab reading 75% RH or less. This process is not 100% foolproof and so during screeding an extra pair of hands is useful to tuck the materials together until the weight of. Ask yourself where the gallons and gallons of water in the slab are going to go - apart from potentially lifting the DPM it will come through any defects in the DPM and cause problems. They are happy for the 25mm board to be laid on the screed, pipes clipped in then 9mm ply on top finally topped off with ceramics. Description. I moved into my new build nearly 2 months ago now and am having quite a few issues. The DPM should come up in an upstand and tie into the DPC on the. It should be waterproof to prevent any rising damp getting through. Express Liquid Screeds Limited. New-build install: £50 to £75 per square metre. F. Jan 24, 2019. Any existing floor screeds, coatings or adhesive residues. The Concrete slab will have been placed in January so it's had about 8 months to dry out.