Not sure on your total thickness of insulation let?s say 100mm Ground Floors. Slab-on-grade insulation. Insulation can be added over the existing concrete slab or underneath a new one. However, it does present a problem that putting poly above the insulation can help with - small beads of EPS making their way into the top surface of the concrete. Points noted regarding the potential downsides though. Mannok Therm Floor / MF PIR Insulation Boards, Insulating solid ground floors below ground bearing slab, Insulating solid ground floors with a timber floating floor, Insulating suspended beam and block floors, Insulating suspended timber ground floors between timber joists, Insulating suspended timber floors other than ground floor between timber joists, Insulating a pitched roof above the rafters: warm roof insulation, Insulating a pitched roof above and between the rafters: warm roof insulation, Insulating a pitched roof between and below rafters: cold roof insulation, Insulating a loft or attic wall in pitched roof space, Insulating a flat roof with concrete deck, Insulating a flat roof with timber deck insulated above the joists: warm deck insulation, Flat roof: timber deck insulated between and below joists: cold deck insulation, Insulating masonry cavity walls with partial fill insulation, Insulating masonry cavity walls with full fill insulation, Insulating masonry cavity walls with internal dry lining, Insulating solid walls with internal dry lining – insulation boards fixed to battens, Insulating solid walls with internal dry lining – insulation boards fixed by battens, Insulating solid walls with internal dry lining – insulation boards fixed by dabs, Insulating timber frame walls with weatherboards. You?ll need a perimeter 25mm upstand The DPM should extend up the external foundation walls to meet the walls’ damp proof course (DPC). With EPS being greener than XPS, it seems a sure winner for below slab applications. 6. I think a gutter downpipe on my house is blocked. Any radon barrier should be laid beneath the slab and should extend across the whole footprint of the building. Can you push a spiral drain unblocker up a downpipe from below? ... DPM/Radon barrier, concrete slab, insulation, polythene separating layer (500 gauge poly), UFH pipe worked clipped, screed. Lay floor insulation boards (Mannok Therm Floor / MF PIR insulation boards or Mannok EPS insulation boards) on top of the DPM in a break bond pattern across the whole floor. Insulating solid ground floors above ground bearing slab. The floor can be a beam and block (also called block and beam, or pot and beam) deck or, on larger projects, a precast concrete plank craned into position. Have you considered putting 2 layers in? Insulation Below A Groundbearing Slab – Design Guidance The Ballytherm boards should be laid on top of the DPM / radon barrier to protect the boards from ground moisture and contaminants. If the slab has hydronic tubing, the minimum R-value of this insulation increases to R-15. Sigh....propelling pencil for marking up? If a below slab arrangement is desirable, however, Polyfoam Floorboard Standard will adequately bear the imposed loads. This 1990 house has 4 bedrooms, all upstairs. 3 Under Slab – ground floor or basement floor in direct contact with the ground, susceptible to losing heat, requiring robust insulation to improve thermal performance. Install a strip of edge insulation (Mannok Therm Floor / MF insulation) around the perimeter of the room against each wall to reduce heat loss through thermal bridging. 1. If insulation is installed above the slab, the building will respond much more quickly to the heating system. The DPM should be laid on sand blinding to prevent puncturing and joined to the DPC at all edges. This slip sheet will also function as a vapour control layer (VCL), reducing the risk of condensation forming beneath the insulation. Installing floor insulation boards above the concrete slab and below the floor screed is an effective insulation method particularly for underfloor heating systems where the underfloor heating pipes are contained within the floor screed. 5. HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. on external walls to stop the cold bridge anyway cost wise apart from a little If the insulation is installed below the slab, this increases the thermal capacity of the building, helping to maintain steady internal temperatures. I thought this article was reasonably interesting: <>You'll see where the UK... Hi friend. Protect the exposed top of the perimeter insulation from any damage until covered by skirting or wall finish. below grade) to have R-10 vertical insulation at the slab perimeter, extending downward from the top of the slab to a depth of at least 2 ft. Follow local building codes or check with structural engineer for correct compressive strength (PSI) for your application. Floor Insulation - Insulating a solid ground floor below the ground bearing concrete slab can be done using either PIR insulation boards or EPS insulation boards. 2. Ground floor – insulation above concrete slab. U-value results above based upon floor construction shown: Radon barrier / DPM; 150mm concrete; Mannok Therm Floor / MF; 60mm sand/cement screed with U/F heating pipes; timber flooring (floor finish omitted); Mannok Therm Floor / MF vertical edge insulation. We use cookies to ensure that we give you the best experience on our website. A correctly specified membrane can function as DPM and radon barrier. One arrangement may be more conducive to maintaining a continuous thermal barrier from a wall down through its foundation but it allows unsightly exposure along the building perimeter. DPM above or below concrete slab. For example, installing a below-grade insulation rated for 100 psi, when only 40 psi is needed, will nearly double the material cost. First, the standard defines two classes of slab-on-grade: Heated slab-on-grade floor: a slab-on-grade floor with a heating source either within or below it. sulation-over-slab and the potential for this feeling slightly warmer under Two of the rigid foam insulations most commonly used below grade and under slabs are expanded polystyrene (EPS) and extruded polystyrene (XPS). Once the ground bearing concrete slab has been laid allow it to dry fully and ensure it is level and smooth, free from projections. Followers 1. I am currently planning the construction of a 15m2 ground floor extension t. Thanks everyone for the input; there seems to be a slight preference for in Thermal insulation is positioned above a ground floor slab when the building’s heating is used intermittently – like in many homes, where it is often switched on in the morning and again in the evening. Suspended floorsare usually insulated in such a way that they offer reduc… EPS can be a cost-effective alternative to PIR for floor insulation, and the same thermal performance can be achieved with increased thickness. Installing floor insulation above the slab and below the screed. Not sure on your total thickness of insulation let?s say 100mm Put 75mm under slab and 25mm above slab. Insulation above the floor slab Insulation is placed above the concrete slab, along with a separating/slip layer and then a rigid floor which is generally either screed or boarding. Installing floor insulation above the slab and below the screed 1. >>> I went for insulation below the slab as I thought insulation with just screed over would be a bit "wobbly" with a spinning washing machine on it (wait for someone to say should-a bought a Miele). foot appeals. Positioning the thermal insulation directly below the underfloor heating system improves the responsiveness of the heating system by isolating the thermal mass of the concrete slab from the building interior, meaning the internal rooms will heat up quicker. Welcome to MANNOK, the new name for Quinn, Click here to find out more about our new brand, Mannok Therm Floor / MF PIR insulation boards  EPS insulation boards, Screed with u/f heating pipes on separating layer, Timber flooring on polyethylene slip sheet. Which size lead? Let's unpack the issue in the context of ANSI/ASHRAE/IES Standard 90.1 - Energy Standard for Buildings Except Low-Rise Residential Buildings. Radiant tubing was at the bottom of the slab, in this area more than seven inches down in the concrete, and set atop the foam sub-slab insulation. Lay an appropriate damp proof membrane (DPM) with joints well lapped and folded. Designers generally insulate both directly under the slab and around the perimeter as well. ... With these the floor can be broken up & removed allowing you to dig down & lay a better grade concrete floor slab with a dpm either below or above the slab. The slip sheet should be taped at the joints with 150mm overlaps and turn up 100mm at the wall junctions. Where insulation is placed above the slab, the rooms will warm up more quickly when the heating is switched on. Yet, slab-on-grade insulation can be arranged in a number of configurations, each with pros and cons. I am currently planning the construction of a 15m2 ground floor extension to our lounge and am torn between having the insulation above or below the concrete slab. The edge insulation should be at least 25mm thick and height should extend from the top of the concrete slab to the top of the finished floor screed. Unheated slab-on-grade floor:a slab-on-grade floor that is not a heated slab-on-grade floor. Use a thin sand blinding to level floors if required. EPS does not experience such “thermal drift,” and the reported … Then insulation & flooring on top to match the floor level in other rooms. It seems like it should not be so complicated. Note, wall insulation in the perimeter walls should also extend at least 150mm below the top of the floor insulation boards.4. Although both are closed cell insulations, they perform very differently over the long term. Put 75mm under slab and 25mm above slab. I am setting up my nice new Combi heating system. All logos and trade names are the property of their respective owners. The insulation boards should be butted tightly together at the joints and should be cut neatly around service penetrations to minimise thermal bridging heat loss. DPM above or below concrete slab Sign in to follow this . Most domestic projects use a floating floor arrangement, with insulation installed above the floor slab or suspended floor deck, and below a screed or board covering. Additionally, the homeowner wanted 10-inch-wide plank flooring throughout most of the house, so the subfloor had to be solid and sealed from any moisture from below. Where radon control measures are required, the specified DPM should be gas resistant. By continuing to browse the site, we will assume that you are happy for your web browser to receive all cookies from our website. Heated slabs-on-grade will feature hot wat… Insulation above the slab increases the heating response time. Lay a polyethylene separating layer across the top of the floor insulation to isolate it from the screed and prevent concrete working down between boards. The floor insulation can be placed under the slab or between the slab and the floor screed. If the insulation is installed below the slab, the thermal capacity of the building is increased, helping to maintain steady internal temperatures. Slabmate is the new under slab insulation solution for slab on ground construction.Slabmate has been designed to create a thermal barrier adding to the total insulation of the project.. Environmentally friendly, Slabmate is made here in Australia for both commercial and residential projects.Slabmate is lightweight, safe and easy to install and will maintain its R value for the life the building. The U.S. Department of Energy (DOE) estimates insulating the exterior edge of slabs in slab-on-grade buildings can reduce winter heating bills from 10 to 20 percent. › Place the uncoiler in an “out of the way area”, still 1 Likewise, the lack of insulation on below-grade foundations, crawlspaces, and under slabs accounts … Insulation Below A Groundbearing Slab – Design Guidance Do not build load-bearing partitions off the slab, all partitions require their own foundations. Insulation below the slab suits continuous, low level heating, gradually warming the thermal mass of the concrete and sustaining it at a consistent temperature. Many increase the under-slab insulating foam board thickness to … labour is the same just make sure slab is smooth. Our photo above on this page shows that tubing was in some sections more than 18" deep, and adjacent to a large area where sub-slab insulation was simply omitted by the contractor. Ground bearing floorscan include insulation either below or above the concrete slab, the choice the designer makes will have an impact on the temperatures inside the building, as follows: 1. SLAB ON OR BELOW GRADE WITHOUT UNDERSLAB INSULATION › Although not recommended for most applications by MrPEX® Systems, this is the prescribed method. The foundation system for this high-performance home was to be slab-on-grade, and we were aiming to achieve R-15 to R-20 of slab insulation in our zone 5 climate. – The space above is conditioned – Slabis onefoot or less below grade Summary Slab is one foot or less below grade • R‐10 insulation required, extending… – 2 feet below grade for climate zones 4 and 5 – 4 feet below grade for climate zone 6 • Insulation should extend downward from the top of You?ll need a perimeter 25mm upstand on external walls to stop the cold bridge anyway cost wise apart from a little labour is the same just make sure slab is smooth Confirm with your engineer what strength is needed. Positioning the thermal insulation directly below the underfloor heating system improves the responsiveness of the heating system by isolating the thermal mass of the concrete slab from the building interior, meaning the internal rooms will heat up quicker. Please view our Cookie Policy page for further information on cookies used by Mannok. The insulation is normally placed below a timber-based flooring system or below a relatively thin sand cement screed. Where the heating is likely to be turned on and off, such as in new-build domestic properties, and a faster thermal response is required, the ‘floating floor’ arrangement of insulation above the slab can be more appropriate. I am planning a kitchen extension (victorian house). If a below slab arrangement is desirable, however, Polyfoam Floorboard Standard will adequately bear the imposed loads. 3. I have a 1x6 soffit board, and am planning on installing vents.Have a look at... and what is a minute or second if not a unit? 2. This option just seems more solid to me. Below-grade insulation enhances thermal performance in buildings and helps protect concrete from freeze-thaw damage. Finish with the floor screed, ensuring that the insulation boards are fully protected from damage in the process. For help and advice on any of our products and how they might fit your needs please contact our Technical by Mannok team. XPS has a higher initial insulating R-value than does a similar thickness and density of EPS, but the R-value of XPS degrades over time. Calculations performed to BS EN ISO 6946 and BS EN ISO 13370, taking account of repeating thermal bridges. Insulation can be installed above an in-situ concrete floor as long as the dpm is placed above the structural slab to reduce the risk of damage to moisture sensitive floorings. Insulation also acts to prevent draughts coming up through the floorboards. The DPM should be laid beneath the slab. In cold climates it is advisable to use a minimum of 2 inches of extruded polystyrene under the slab. Compared to the wet trades involved when insulating above or below a concrete slab, suspended concrete floors offer a fast, effective, dry operation. By BMcN, February 12, 2019 in Floor Structures. Temperatures will increase more quickly when the heating system is switched on in comparison with below slab insulation The insulation zone can be used to run services and underfloor heating The effect of … The damp proof membrane (DPM), which can be either above or below the slab, must be continuous with the damp proof course (DPC) in the surrounding walls. Exposed Floors – floor suspended above a crawlspace, requiring optimum thermal property insulation because of high heat-loss risk. In climate zones 4 and 5, the code requires certain slabs (below-grade slabs that are less than 12 in. Most domestic projects use a floating floor arrangement, with insulation installed above the floor slab or suspended floor deck, and below a screed or board covering. Any DPM needs to be positioned on sand blinding (maximum allowable deflection +/- 5 mm over 3m length) to avoid puncturing; attach to … >> >> With ours being a lounge I am assuming that loadings should be fairly static and spread out. Background radiation levels in England and Wales. Ground bearing floors can include insulation either below or above the concrete slab, depending on the choice of the designer. There are arguments for, and against both, but if you are to use an underfloor heating method of some kind the insulation is often placed on top of the floor slab, under the screed.