Type-I is too easy damager or to leave permanent boot tracks in, even though it's still strong enough once the slab is installed. Using the above method to determine the pressure that a slab transfers to the subgrade allows for proper specification of rigid foam insulation and avoids over-engineering the insulation for compressive strength. Thank you for all the helpful information. I also see that he is installing 40 psi foam under the spread footings too. There are two type of insulation - 30 psi and 45 psi These numbers are the crushing strength at yield or a 10% deflection (whichever comes first). A well-insulated concrete slab ensures that the thermal efficiency of the property is controlled and maintained. Example: http://foundationhandbook.ornl.gov/handbook/images/Chapter%204/4-11_no-cap.png, The Type I EPS is rated at a compressive strength of 15-21 PSI, the Type IX is rated at 25-33 PSI. Moreover, and more importantly, the owner is refrigerating the slab with cooling coils and insulating under the slab of which I was not aware. Below-Grade Under Slab with FOAMULAR® XPS insulation. For example, with a forklift load on a typical 4-inch-thick slab, one calculation would indicate that 32 psi is applied to the insulation compared to only 2.5 psi under a more accurate calculation. XPS and EPS rigid insulation is used under concrete slabs. Q.How much insulation is necessary under a typical radiant slab? of sand. But under footings or load bearing posts it may need to be something denser. In the example application discussed in this article, the simplifying assumption of triangular load transfer through a concrete slab results in a compressive force on the insulation 11 times higher than the result from the more rigorous (but not much more complicated) analysis. A common, simplifying assumption used for specifying polystyrene insulation under concrete slabs results in material costs that are significantly higher than necessary. 60 psi minimum FOAMULAR® 1000 XPS Insulation: ASTM C578 Type V, 100 psi minimum Description Owens Corning™ FOAMULAR® 400, 600 and 1000 are high strength Extruded Polystyrene (XPS) Insulation products designed for use in engineered applications requiring additional load-bearing capability such as under slab, concrete fl oors, Will those areas compress immediately as the slab is poured or will it result in later cracking from uneven settling? The best option for residential floors is Foamular 250 foam board, which provides R-5 per inch of thickness and 25 PSI of compressive strength -- which is ideal under or over a concrete slab. EPS insulated concrete forms (ICF) are all Type-II, and it is sometimes quicker / easier / cheaper to pour the stemwalls in ICFs, unless you find a source for used roofing EPS, which is almost always Type-Il, to enable a "walkable" membrane roof. Reclaimed EPS from commercial building re-roofing/demolition is fairly ubiquitous and cheap, typically 1/4-1/3 the cost of virgin stock goods from salvage outfits and foam reclaimers. The value of R. e3. Below-grade insulation enhances thermal performance in buildings and helps protect concrete from freeze-thaw damage. A concrete slab must be capable of distributing loads over an area of sufficient size so that pressure on underlying layers does not exceed allowable limits.When FOAMULAR® Extruded Polystyrene Insulation is used below the slab, allowable stress limits are defined based upon a percentage of Foamular® insulation’s minimum compressive strength. (If you live in Olympia you don't exactly want to be shipping it from Spokane, but Portand or Bellingham wouldn't be out of the question.). If a vapor barrier is required, make sure a suitable type is put down before the foam insulation. Taking into account the fact that concrete slabs distribute loads more evenly, using the Modulus of Subgrade Reaction method, the pressure on the insulation is actually much lower – approximately 1.85 psi. CAN/ULC -S701 01,ASTM C518 5.4 40ºF mean temp. Extruded polystyrene closed-cell foam, ASTM C 578 Type IV, 25 psi minimum Shipped in poly-wrapped units with individually wrapped or banded bundles. Martin Holladay explains insulating a slab on grade in the Energy Smart Details department. Mike McCann Its compressive strength is similar to sandy soil. The stuff here is typically 25 psi; I was advised by an engineer to use the 60 psi under a garage slab, and I think that is also OK under footers. 100 PSI minimum EXTRUDED POLYSTYRENE (XPS) RIGID FOAM INSULATION Owens Corning® FOAMULAR ® & FOAMULAR NGX™ 400/600/1000 are high strength Extruded Polystyrene (XPS) Insulation products designed for use in engineered applications requiring additional load-bearing capability such as under slab, concrete floors, foundations, Designers generally insulate both directly under the slab and around the perimeter as well. I have spec'ed freezer slab insulation a couple times in the past and have talked to DOW about how they come up with their numbers. Avoiding this error requires taking into account how the slab and sub-grade interact. Insulating the slab Using rigid foam insulation around the perimeter of the slab to minimize heat loss seems like an obvious step, but whether to place insulation under the slab is another story. For almost all residential slab applications Type-II EPS is fine. Although both are closed cell insulations, they perform very differently over the long term. The specification fiber-reinforced concrete of be performance-based shouldand dependent on the Michael, With the widest range of faced, laminated and standard high-performance EPS insulation products Insulfoam has the right products for your needs while still providing the highest R-Value per dollar over any other rigid insulation. When building a slab on grade, EPS rigid foam insulation is the most common choice of insulation, for performance and cost. http://www2.owenscorning.com/worldwide/admin/tempupload/pdf.077_HighDensity_E_1.pdf. Appleguy, 15 psi foam--that is, foam tested to deform no more than 10% of its thickness under a 15 psi load, is strong enough for use under most slabs. EPS insulation in an under-slab application. Concrete shall have a minimum specified compressive strength of f ' c, as shown in Table R402.2. Akron, OH 44305 Monday: 7:30 am – 4:00 pm Tuesday: 7:30 am – 4:00 pm Wednesday: 7:30 am – 4:00 pm Thursday: 7:30 am – 4:00 pm Contact Us: Click here to contact the Insulfoam location near you. For Under Floor Slabs, FOAMULAR® 150 or 250 can be used for residential and light commercial applications where floors are subject to normal loads; use FOAMULAR® 400, 600, or 1000 for industrial applications where floor areas will be exposed to heavy loads. A hydraulic pressure pump is used to inject polyurethane foam under the slab, ... (64 kg/m3) 60 psi (413 kPa) 6.0 (96 kg/m3) 110 psi (758 kPa) Polyurethane Foam: Polyurethane foam has a minimum compressive strength of 40 psi (275 kPa). How about factory seconds where the boards are not of uniform density? Insulation located below grade, as required in Climate Zones 4 through 8, should extend the length specified in the table by any combination of vertical insulation, insulation extending under the slab, or insulation extending out perpendicular to the building Insulation extending perpendicular away from the building should be protected by pavement or by not less than 10 inches of soil. We have to install 150 sheets total of 2" XPS foam so the radiant guys can come in and set up. Click here to contact the Insulfoam location near you. Two-pound foam. rigid foam boards well suited to meet the needs of a wide variety of building applications. Insulating a slab on grade depends on at least four factors: the climate, the type of foundation, whether the slab includes hydronic tubing for radiant heat, and the severity of the local termite problem. This feature has been temporarily disabled during the beta site preview. This won't delete the articles you've saved, just the list. There needs to be a vapor retarder at least 6 mil between the base course and the slab. Get all the construction documentation you'll need, in a single click: Specify This Solution ZIP | 4.8 MB Residential PV Installations in Florida Remain Strong. There is the perception that the extruded styrene (blue or pink board) is required for under slabs, yet the white board (expanded EPS) is often significantly less expensive for such projects. Under Floor Slabs. For foundation and wall applications in which the foam insulation bears a minimal load, ASTM C 578 Type I (nominal density of 0.9 pounds per cubic foot) material is adequate. To receive insulation and Insulfoam updates, join our email list, Log in 1 Both products are great for above-and below-grade residential and commercial applications such as perimeter/ foundation, cavity wall, precast concrete, under slab, and other applications. If the designer assumes that this load distributes at a 45-degree angle through the slab, the 8,000 pounds ends up distributed over … 6. EPS does not experience such “thermal drift,” and the reported … A 4" slab contributes about 50 psf of load; add a 40lb live load and you're still below 1 pound per square inch. Two-pound closed-cell foam has a compressive strength of 20 to 30 psi (depending on the specific brand used), which is generally acceptable for a typical nonload-bearing residential slab. Two of the rigid foam insulations most commonly used below grade and under slabs are expanded polystyrene (EPS) and extruded polystyrene (XPS). In cold climates it is advisable to use a minimum of 2 inches of extruded polystyrene under the slab. Under Slab FOAMULAR® 400 40 psi IV IV R-5 R-10 1" 2" 24"x96" 24", 48" and 96" For under slab, concrete floors. Only closed-cell SPF can be used in a subslab installation; the open-cell foam does not have adequate compressive strength. The compression curve for foam plastic is usually pretty straight, so insulation rated at 15 psi would compress somewhere in the neighborhood of 0.015 of its thickness. Its formulation will reach 90% of full compressive strength within 15 minutes from injection. Compressive strengths†from 30 psi to 100 psi (210 kPa to 690 kPa) to meet the requirements of nearly every application. The compression curve for foam plastic is usually pretty straight, so insulation rated at 15 psi would compress somewhere in the neighborhood of 0.015 of its thickness. There are two type of insulation - 30 psi and 45 psi These numbers are the crushing strength at yield or a 10% deflection (whichever comes first). Spray foam really is a magical tool for household insulation. We have to install 150 sheets total of 2" XPS foam so the radiant guys can come in and set up. CAN/ULC -S701 01,ASTM C518 5.6 25ºF mean temp. Forklifts to be used in the building impart 8,000 pounds of force at the wheel, which has a 6 … this gives water in cement somewhere to go besides up. For 3" foam, that's less than 1/16". Many increase the under-slab insulating foam board thickness to 3 or 4 inches at the outer 2 to 4 feet of the slab. I figured I would verify his recommendation by asking folks who have used EPS in this sort of application in the real world who don’t have sales bias , Our foundation is a 4″ slab with 6″ thick stem wall, 3″ inches of rigid EPS under the slab and another 3 inches on the outside of the exterior of the stem wall. Benefits of foam insulation under concrete slab . Type 9 is better for areas that support roof upper floor loads, such as below footings. Thickness Many designers assume that a concentrated load applied to the slab transfers to the rigid foam subgrade through a triangular load path. 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