ORDER LINE 0800 047 6775. What the DPM is attached to can fail. Laybond Screedmaster One Coat Liquid DPM 2 part solvent free epoxy surface damp proof membrane developed to. Had a look at the pics and IMO no dpm under the subfloor. If in the screed then no problem with this. I was with Mapei last week inspecting a failed DPM that had been laid on a subfloor with no DPM under it. Warm water underfloor heating. Alan Jackson - Commercial Manager UK and Ireland - Gypsol. Ie work down from FFL. Damp proof membranes (DPM) A DPM should be a minimum thickness of 1200g polythene and linked to the DPC with a minimum 100mm overlap. Answered 22nd Aug 2016. Easy Handling & Installation. 4 Apr 2017. 6 March 2017 at 8:04PM edited 6 March 2017 at 8:59PM. Country. co. Small hole dug through 2" soft sandy concrete to reveal hardcore and soil. 15) DPM under screed. 19 Mar 2011. Liquid DPM for Walls. 500g Single Wound Polythene-2. We have our own in-house delivery fleet of FORS Gold vehicles with Moffett mechanical off-loads delivering nationwide. hallbeck, Jan 26, 2010 #5. We’d recommend using timber battens to act as a guide – apply a small amount of screed to the flooring to lay the battens on, and lay the battens in strips across the floor. DPC and DPM are lapped together at this stage. USES For priming, consolidating and sealing of: Absorbent and non-absorbent sub-floors, consolidat-ing weak cement screed and isolation of old adhesive residues. The purpose of DPM. For example, when installing Celotex under floor. BAL DPM is resistant to water, chemicals, grease and pollutants, and can be used internally or externally either as a DPM, primer, waterproofer or residual m. Discussion in ' Builders' Talk ' started by Liz990, Feb 21, 2021 . weberfloor DPM can be applied on to concrete or cement based screed surfaces with a. Insulation is laid on the concrete and covered with a screed. I really need to get the living room useable for my family and am hoping that a dpm under the engineered wood is possible. You are talking about a solid concrete floor which has to be on load bearing stable ground. The Epoxy DPM 5kg is supplied in two 2. 3. 100m² per roll. 5. A section of the old screed layer has broken up around the edge of the patio door threshold. VCLs prevent excess moisture entering a wall’s cavity, behind the insulation. 12 Sep 2015. Some houses in early 70s don't have a DPM as I've found out over the years. com. DPM’s can be applied to either a suitable blinding layer under the slab or internally to the top of the slab. 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. DPM, Celotex, 1000 gauge poly, 100-150mm concrete with or without reinforcement, 50-80mm screed. My DPM was these tiles that were bitumnned/black jacked to the floor. Put an upstand of 25mm celotex around the perimeter of the room and a dpm under the concrete lapped up the walls, being higher than the dpc won’t matter Jimmycloutnail, Jan 23, 2019 #4. DPMs on top of the slab, i. Before screeding can commence the area to be screeded must be made watertight to prevent leakage. "Remove water with pumps or buckets and contact your insurance company straight away. As a waterproofer, BAL DPM is an easy two-coat system when used with BAL Self-Adhesives Butyl Tape in corners and junctions. Hi, I'm doing a kitchen modernisation in my ex-Council house which was built in 1947. Depends where the UFH pipes are. Or have you asked them can you install Surface DPM on a Wet subfloor that does still have a DPM under it? Don't confuse the TWO. Sunny Hampshire. When sand-blinded, BAL DPM allows tiling onto difficult substrates such as steel. DPM’s must be carefully protected where folded up the perimeter walls, and lapped under the DPC particularly at door openings. If you noticed the buildup wording is different to the detail drawing, it clearly shows dpm on top of concrete. Contact Us. 250mu Polythene DPM is suitable for use as a damp proof membrane under screed floors. When applied on top of screed, it needs to have a further coating to protect it from damage such as laminate, tiles, vinyl, wood and carpets. This reduces the risk of harmful interstitial condensation by ensuring that any moisture within the. Solid floor insulation –screed finish: Per m 2: £70: £90: £80: Labour: Per day: £180: £250: £215:. Contractor wants to paint Sika Primer MD on top of the self leveling compound. Sealing a patch of DPM around its edge to the old is easy, just use silicone goo. 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. Mapeproof One Coat is not recommended for heated subfloors where wood floor coverings are to be installed. I think this is too expensive, so got a quote of another supplier of £2565 plus any potential floor preparation, with latex screen costing £13 /sqm or a feather finish at £2. You adjust the concrete slab to let your. This means of course I can't get a DPM under the slab; is it ok to put the DPM over the concrete slab, and then put down 50mm insulation and then 100mm screed? Ed209 , May 1, 2020 #1Assuming that the damp proof membrane (dpm) under the concrete has failed in areas then yes you possibly would get the odd patch of dampness showing in the floor. Location. The asphalt screed provides a membrane to the surface of the concrete floor preventing moisture within the constructional slab causing decay to the floor coverings. When it comes to the hearth I know that I need to have a constructional hearth at least 125mm thick that extends out 300mm in front of the stove. But on the basis of more insulation is better, consider fitting more and laying cupboard flooring on top, or on joists. It's a small garden room with a 2 course brink plinth, DPC, and then timber sole plate. Fax: 0800 270 7368. The liquid membrane forms a strong seal and makes a permeable layer to enable moisture to evaporate off. We need to raise one level by 6mm then screed then laying 2. 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. 1955 house, recently moved in and presuming no DPM under concrete slab. 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. flooringman Well-Known Member. Damp proof membranes can be used to help resolve damp issues. Flowable liquid floor screed suitable for applying up to a depth of. So, as money's too tight to mention round here, I replaced the leaking door with a cheap UPVc one. The total floor insulation cost will have two elements – the cost of materials and. Hello, hoping someone can help. Insulation Below A Floor Screed. 3. 67. Can be used over underfloor heating. I'm thinking dpm under the floor board and then 3:1 motar under the DPM to bed on the blocks. It has to breath to survive. Water is added to ensure a thorough mix and to aid workability. Information ARDEX DPM 1 C. Relative Humidity: The moisture content or relative humidity of the atmosphere plays is a major factor that affects the drying time of the screed. TB243. screed (with UFH) 75mm. The purpose of DPM. The tiler can then latex or screed over the DPM. An ARDEX Damp Proof Membrane will protect the floorcovering. These black DPMs can also be used with underfloor heating - under normal operating conditions this will not adversely affect the membrane. Temporary protectionI had part of a 9" wall knocked down for a doorway. 21. You will need to tear the lot up. #2. 28 Sandiwch damp-proof membrane. LKAB Minerals +44 (0) 7966 651006. If you don't allow the screed to dry properly, the moisture will be trapped within the screed potentially causing failure. I would also gripfill under the plate to supplement the fixings if it were screed. It is essential that this. Country. The. Mobile Sales: 07920 715745. Capital Valley Plastics Ltd Damp-Proof Membrane Black 1200ga 25m x 4m (47163) (55) compare. Our highly experienced team of technical experts are here to offer help and advice every step of the way! Dependable Deliveries. It stops around 10mm away from the internal walls in all rooms. 8). take account of possible differential movement. DPM’s can be applied to either a suitable blinding layer under the slab or internally to the top of the slab. The excellent adhesive qualities and quick drying time of Drybase Liquid-Applied DPM make it extremely versatile. Pumped anhydrite floor screeds are not much dearer than ready-mix sand/cement, costing around £25/m3 (laid. #1. do I still need a DPM under that insulation? it is internal and sitting on a structural slab that is wrapped in DPM externally. Ideal for use where there is no functioning structural DPM (common in older properties). Brief background: After buying a 1960s semi in south Birmingham house last year, and spending the summer managing (a) complete rewire; (b) installation of satellite and Ethernet wiring to all rooms; (c) plastering to make good chasing from (a). 50 /sqm. 0113 2455450 sales@rawlinspaints. Use polyethylene sheeting to create a waterproof membrane to ensure that there is no leakage of the screed when it is pumped in wet. Insulation sheets should be laid tightly together with the joints staggered to avoid movement. Our expert team are ready to offer you the very best solution for waterproofing. But this all begs the question of why the hallway is so wet. Then once the screed is dry use a liquid DPM such as F-Ball Stopgap F77. DPM, Celotex, 1000 gauge poly, 100-150mm concrete with or without reinforcement, 50-80mm screed. Based on a screed done in 1963 I’d say 95% there won’t be a effective damp proof membrane under it so a. Reinforcing concrete. Coverage: Approx 6 m at 3 mm thickness. Two coats will provide protection up to a maximum hygrometer reading of 95% RH. The advice of a structural engineer should be sought for any exceptional point loads in the design of the floor. The company keeps abreast of market developments by. #2. If there was no dpm I would suggest a uniformal distribution across the whole floor. phatboy. 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. The buildup is. Celotex PIR’s closed-cell, moisture-resistant composition helps to prevent water ingress. 00. If the coating is not going to be the final decorative surface and. Walkable in 6 hours. I will be tiling over the screed so looking for the simplest option. Then the lamiante has trapped this water in creating the sweat. weberfloor flex is a self-smoothing floor levelling compound — often incorrectly referred to as a self levelling screed or self levelling floor compound — which can be tiled onto and is an easy screed for applying onto floor substrates subject to some movement, such as wood or underfloor heating. 9% screeds been down since February. The oversized DPM was instead lapped with the DPM that was placed under the screed. Liquid DPMs gave the best protection but were more expensive. Used the primer neat as guidelines suggested. Last autumn we knocked down an old conservatory and kitchen extension and built a new extension in the same place. The DPM (Damp Proof Membrane) is laid under the insulation on top of a soft blinding to ensure it is not punctured. Screeds are covered by BS 8204, Screeds, bases and in-situ floorings, (2004). "Document any damage for insurance purposes. By definition, Relative Humidity (RH) is a measure of the amount of water vapour present in the atmosphere relative to the amount of water vapour it can hold at that given temperature. above the slab I am having a screed to cover the UFH pipes. However, when I hammer-fix the battens to the concrete I'm going to punch holes in my DPM. jeds. Description. FlexiDry said: Yes laying the screed direct onto insulation is standard practise for a floating floor. DPM’s can be applied to either a suitable blinding layer under the slab or internally to the top of the slab. Developer has quoted £3744 for approx. In these cases the insulation goes on top of the slab. Ideally there should be a fully working dpm under the main concrete slab but where this does not exist or where the time for the slab to dry out sufficiently is longer than the building programme can permit, a dpm can be included either above or below the screed. 2. Figure 3: Concrete masonry foundation wall and concrete floor. However the tiler should apply a Primer before screeding such as StopGap P141. The problem is by the time we insulate, screed and lay the flooring we will be above the dpc& membrane level by 4 inches. Slightly below floor level are two layers of polythene membrane with a layer of floor levelling screed to make up to floor level. It is not. Let’s hope you have a good water table as that’s the wrong dpm used. WoodYouLike. Could us a liquid dpm like Drybase (2 coats), then a sand/cement screed,with fibre reinforcment, 25mm is the minimum thickness for bonded screed, that's thin,might still crack, no need for primer with Drybase. If I did my external one at the same height then the outside floor height would sit very low so presumably I can put the external one at the same level as. Go for the application of a surface DPM; The third option is however quite expensive, and could turn out to be more expensive than the screed itself. This allows for the full 5kg or just half to be mixed at once depending on the area to be covered. There is a membrane underneath the concrete slab which has been poured and it comes up and meets the dpc. 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. ) • Floating (used to enable installation of thermal or impact sound insulation). Guide Underfloor heating A guide for house builders NF71 NHBC Guide to Underfloor Heating 2nd draft RH. DPM Membranes for Concrete Floors A range of high quality DPM membranes from Capital Valley Plastics, designed for use with solid concrete slabs. Lay the damp proof membrane (DPM) (normally 1200g polythene sheet/300g micron or a radon barrier if specified), over the sand-blind base. The concrete slab was usually 100 to 125mm thick. Hi, just laying insulation on 1200g DPM and now looking for a cheap / simple VCL to lay on top of the insulation and under the screed. The work falls under building regs part L and you need minimum 70mm PIR insulation. #2. I am assuming its asphalt with a bitumen top layer, 10-15mm thick. Im surprised the floors lasted that long 300 will fail over bitumen everytime. "Turn off electricity and gas only if it’s safe to do so," he said. A poorly compacted, damaged or weak screed should be completely removed by mechanical means and reinstalled correctly. you might just have a low spot along the old wall where the concrete meets the wooden floor. There are two main options: 1. Brian shows how to correctly fit a Damp Proof Membrain - DPM in a new build houseLink to the T-Rex tape Website Http://bodgeitwithbri. hallbeck New Member. will come down and meet the insulation under the screed so the screed is totally floating. As with the Kooltherm installation, start by ensuring a clean and level surface. Because we were laying Karndean Flooring to a new extension we needed to check the % RH(relative humidity) of the concrete with a hygrometer. All other sheet membranes can be used with unbonded toppings. 16) Concrete slab 300mm. Small domestic areas that are going to have carpet, wood or synthetic floors as the final surface are ideal to use in conjunction with. LKAB Minerals +44 (0) 7966 651006. This barrier is intended to stop moisture passing from one to the other. 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. 4 Screed. 8 Apr 2013. Country. Nice. Issues to be taken into account include: installation. Guarantees the early laying of all floorcoverings. SikaBond® Rapid DPM is a single part moisture curing polyurethane. It also looks like there could be polystyrene under the screed, this will be a barrier to damp coming from the ground. Maybe better to use a fibre based leveling compound instead, like Granfix Fibreflex 50 or similar. Bonded Screed Maximum Depth. #1. Should I lap DPM under or over Dpc then celotex, then another DPM lapped up the wall with. However the tiler should apply a Primer before screeding such as StopGap P141. We are in the process of having an extension built. I always put the Celotex under the slab to ensure that it doesn't deteriorate between laying it down and screeding. Floor under carpet marked with chalk for wet areas. top of my concrete slab was about 50mm below DPC, I finished with battens and floorboards. The damp proof membrane (DPM), normally 1200g polythene or radon barrier, should be laid over the blinding,So not convinced glue down is right. The bitumen is about 20 mm thick and, I believe, serves as moisture barrier as well as an 'appearance' finish. Do you know whether the fitter did any kind of damp proofing under/on top of the screed? And have you had any damp problems since then?Screeds – general. 2 of the internal walls in the older building will be left as bare stone,. The floor make up is compaced hard core, 125mm concrete, dpm, 100mm insulation, 75mm concrete screed ( polished and heated). Issues to be taken into account include: installation. Renovation property: £60 to £85 per square metre. Notch7. The membrane is manufactured in standard 125mu, 250mu, and 300mu thickness and in roll sizes of 1. 5sqm has blown. I'm not saying this is the best thing to use. Ball and Co. Yup so the plan is: Existing garage is concrete which is a 75mm lower than the current house level. Suitable for most construction damp proofing requirements. 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. above the slab I am having a screed to cover the UFH pipes. Currently, the central heating pipes and mains water pipes are all buried below the damp proof membrane, under the screed. Seems fine so far. Get it level then when it is dry and can screw through floor board into blocks. Our self levelling compound, or floor screed, is available in a wide range of varieties for a multitude of floor installation applications. 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. It should accommodate 0mm to 5mm (or thereabouts) It will cover an area of 26m2 (4m x 6. In the attached photo I have removed poorly laid DPM and insulation boards with a view to starting again. 3. If DPM ok then. Concrete & Sand/Cement Screeds Concrete and sand/cement screeds must be dry and any laitance or surface treatments removed. Prime and reapply , then screed to level and tile. Brian shows how to correctly fit a Damp Proof Membrain - DPM in a new build houseLink to the T-Rex tape Website Http://bodgeitwithbri. #1. 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. £20 per m2. f) whether there is an effective dpm within or under the existing base; g) whether the screed is to provide the wearing surface, if so, the type and intensity of traffic to be expected; h) if not a wearing surface, the type and thickness of the finished flooring to be applied; i) type of underfloor heating (if any) to be used; applications are suitable for bonded topping screeds. The idea is that you are to prevent any screed material from falling down any joints and coming into contact with the cold slab. Uses/Subfloors:If you have under floor heating, you can use it to dry the screed 7 days after installation and the additional depth, (up to 65mm), becomes less important, But you’re still wasting money on screed you don’t need. The outcoming drain will have the dpm taped to it all the way around. (See FeRFA Guidance Note No. How to screed by hand step-by-step with our stars Luke and Lee who are at the top of their game and Luke is only 18 years old, very impressive. I would lay the DPM straight onto the existing and screed over. 3. 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. studs 63mm x 38mm at maximum 600mm centres. This barrier is intended to stop moisture passing from one to the other. A Vapour Control Layer, or VCL for short, is a plastic layer that restricts the movement of warm, moist air from inside a property into the fabric of the building. 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). moisture can still transfer through the screed albeit at a slower rate. Bring the membrane up the surrounding foundation walls until it is just high enough to connect with or form the wall damp proof course. 00 per roll. Resin and cementitious floor finishes combining performance and design. Step 3: Lay the watertight membrane. 5 ratio of cement to sharp sand. For rafts, DPM and screed must be on top of raft and screed must be at least 65 mm thick. For bonded screeds, M-Bond Extra epoxy resin combined DPM and bonding agent may beToday, new solid floors are far more substantial, typically comprising 150mm of compacted hardcore, 50mm of sand, a polythene sheet DPM, 100mm of concrete, then around 100mm of insulation plus a 60mm screed — in total, more than 450mm thick. Out of the 7sqm of floor i guess about 1. Effectively, a damp proof membrane (DPM) is used to create a barrier between a concrete (or screed) subfloor and a wood floor. 29 per m², £42. Location. It is a thermally effective solution that is equally efficient in concrete floors, beam and block floors, and suspended timber floors. Location. not a good idea man. Firstly, there was no need to use a liquid dpm if you used underlay with a built in vapour barrier. steve have you checked the level of all of the concrete floor. Manchester • Member since 5 Jun 2015 • 64 jobs, 95% positive feedback. He also saw hairline cracks in the top layer of screed in places. So I have a concrete floor in the kitchen (concrete - DPM - 50mm screed), knocked through into the outside toilet which just had soil floor. having a solid wall causes damp bridging problems for the floor (there is a dpm on top of the floor anyway, but the beam and block is supposed to sit on a dpc) as there is no cavity. #1. You can lay a fast track DPM (damp proof membrane) if your new concrete has had 2/3 weeks drying time. Damp Proof Membranes. Walkable in 6 hours. Non-structural floor screeds shall be adequate for the location and intended use, and provide a suitable background for floor finishes. The specific liquid DPM system will depend on the type of substrate or screed. AFAIK - PIR insulation boards need have a DPM under them to protect the board. There will be a DPM under the slab and up the edges already. Pre screeding, you lay the DPM, install the insulation sheets and create vertical upstands of insulation block around the outside perimeter of the wall. Wet underfloor heating. Customer asked me how did they stop rising damp before the Dpm sheet was used and it made me think ( that hurt ) . Covering it in denso tape and maybe putting some dpm over the top before screeding? Yes copper is best and lasts forever, but in this situation what would you do? So far I'm leaving towards plastic which makes like easier, less stress thinking that there are all those copper joints under the screed and underfloor heating. It is important to ensure that a proper seal is achieved around all services. DPC and DPM are lapped together at this stage. The subfloor. All waxes or sealers must be removed, and patching/leveling or embossing must be brought to a flatness of 3/16” in 10’. LAY DAMP PROOF MEMBRANE. DPM over a new underfloor heated screed, the heating system must be turned off 48 hours before application. the advice by these two posters is absolutely incorrect, if your RH% is above 75% you absolutely need a surface dpm and dual screed the test takes 72 hours to take though, depending on size the price you were quoted is reasonable (surprisingly from. So latex one its more likely the addy will be affected. Fast drying screed cost. Thanks for the reply. 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. Also, even with 80mm screed directly over Celotex the sab can feel a bit "hollow". In order to prevent damp rising through the concrete floor and causing issues, a DPM should be used under all final floor types including wood flooring, laminate, vinyl and floor tiles. 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”. Using this latex based damp proof paint as a damp p. g. The specific liquid DPM system will depend on the type of substrate or screed. 5m2 at 1mm thickness 1. The old floor tiles do contain a small amount of asbestos ( Marley tiles etc. The dpm has added to the problem by removing any bonding capabilities within the floor screed. 5kN/m2. 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. Norfolk. Visqueen High Performance Damp Proof Membrane. Hence we always say DONT apply a surface dpm to a subfloor subject to rising damp. The screed manufacturer agrees that their screed can receive an epoxy DPM. 1200g dpm. Spacey Super Moderator Staff Member. As you are always relying on the subfloor surface strength you are always at risk if there is no sheet DPM under the floor as it will be under pressure. 2: Fill the gaps with concrete, lay a DPM over it, insulation, then a concrete / fibre screed. I would think a strip out and start again would be your best option, you should consider where/why there is water evident before. 21m2 1. First, divide the floor up. if no dpm I would blackjack 2 coats on. 18) Bricks. The only way to tell properly, is to carry out a proper test. The following week, I got high moisture readings (90% plus) in several places on the concrete flooring, from a hygrohood I borrowed from a local flooring company. Depending on the use of the building, the slab can then be finished ready for use, or receive a screed suitable for a floor finish. Once set, you can then apply your screed flooring to the DPM base. Material. New-build install: £120 to £135 per square metre. The screed has water anyway, so a bit of ingress isnt an issue. I was hoping to use a recycled content DPM. Can you put DPM over screed? Liquid DPM is a system that is used over a base floor. hot bitumen, or cold bitumen in solution. Im not quite sure where my DPC should be going. Is this okay? Or does this present a real risk of corrosion of the frame in the future?that's rising damp mate, need to dig up subfloor new concrete base, dpm leave 30 days then screed and surface membrane that should help fix the problem. or email. I recently had a new boiler installed and new radiators fitted, and the plumber has cut the old copper. Damp proof membranes (DPM) A DPM should be a minimum thickness of 1200g polythene and linked to the DPC with a minimum 100mm overlap. TiT. An ARDEX Damp Proof Membrane will protect the floorcovering. Gaz, you need to change your message setting as I can't reply. What do think? What if we're pouring one of these strong self. carpet, tiles etc. I was then able to put in a dpm and a hefty layer of cellotex and then screed to the level of the house.