Rigid Insulation Under Slab Detail

Insulation located below grade shall be extended the distance provided in table n1102 1 1 namely 2 ft.

Rigid insulation under slab detail.

Rigid insulation is placed vertically on the exterior face of the foundation wall. The layer of rigid foam insulation that separates the concrete foundation wall on the outside from the slab on the inside. Figure 4 11 illustrates a slab on grade foundation with a masonry foundation wall. In climate zones 6 7 and 8 by any combination of vertical insulation insulation extending under the slab or insulation extending out from the building.

Get free shipping on qualified under slab foam board insulation or buy online pick up in store today in the building materials department. In fact they are almost unintelligible. Moisture control is provided by a vapor retarder under the slab. Roche has paused at an important detail.

4 10 2012 3 climate zones e301 1 6 5 8 4 slab r value table 402 1 1 insulation and fenestration requirements by component e402 1 1 climatezone slab r valued 4 10 2 ft 5 10 2 ft 6 10 4 ft 9. This compliance option is explained this way. Code requirements for slab insulation are very poorly written. Insulation requirements for slab on grade floors can be found in section r402 2 9 of the 2012 iecc and 2015 iecc as well as section n1102 2 9 of the 2012 irc and 2015 irc.

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. R 7 7 rigid foam insulation model 310891 18 35 18 35. In climates zones 4 and 5 and 4 ft. This insulation aligns with rigid foam sheathing that covers the framed walls above grade.

It is installed on the interior exterior or is integral to any opaque surface of the building envelope. For under slab applications the rigid foam insulation typically should be installed over a gravel base with a poly vapor diffusion retarder between the gravel and insulation. 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. Roche writes in a recent q a post that just about every foundation design for a slab that he s seen either puts all of the rigid insulation on the outside of the foundation or.

Additional insulation is applied along the edges of the slab because that is a primary surface for heat loss.