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Slab independent of foundation wall

Slab independent of foundation wall

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Exterior Edge Insulation for Existing Foundation Slabs

Guide

Guide describing how to install slab edge insulation when retrofitting existing slab-on-grade foundations.

Rigid foam wraps the exterior of the foundation slab.

Rigid foam wraps the exterior of the foundation slab.

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In cold climates, install slab edge insulation when pouring slab on grade foundations.

In cold climates, install slab edge insulation when pouring slab on grade foundations.

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Assembly Sequence for Slab-on-Grade Foundation with Concrete Stem Wall and Under Slab Insulation

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Video animation showing an assembly sequence for slab-on-grade foundation with stem wall and under slab insulation.

High-Performance Slab-on-Grade Foundation Insulation Retrofits

Reference

Report assessing slab-on-grade foundation insulation energy savings.

Right - Rigid foam slab edge insulation is installed along the exterior edge of a monolithic slab foundation.

Right - Rigid foam slab edge insulation is installed along the exterior edge of a monolithic slab foundation.

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Rigid Foam Insulation Installed over Existing Foundation Slabs

Guide

Guide describing how to insulate an existing slab floor by adding rigid foam insulation over the slab then installing a floating subfloor.

The home’s slab-on-grade foundation is wrapped in a blanket of rigid foam extending completely under the slab and along the edges.

The home’s slab-on-grade foundation is wrapped in a blanket of rigid foam extending completely under the slab and along the edges.

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Externally insulated concrete slab-on-grade foundation with a turn-down footing, showing anchorage of the wall to the foundation for seismic resistance

Externally insulated concrete slab-on-grade foundation with a turn-down footing, showing anchorage of the wall to the foundation for seismic resistance

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Rigid foam forms an insulating bond break between the foundation wall and the slab

Rigid foam forms an insulating bond break between the foundation wall and the slab

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Rigid foam extends under the full slab and lines the inside edges of the foundation walls.

Rigid foam extends under the full slab and lines the inside edges of the foundation walls.

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Assembly Sequence for Slab-on-Grade Foundation with Integral Grade Beam and Exterior Insulation

Video

Video animation showing an assembly sequence for slab-on-grade foundation with integral grade beam and exterior insulation.

Four inches of rigid foam separate the concrete slab from the ground and the foundation walls.

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Right - Rigid foam insulation is installed along the exterior edge of an existing foundation slab.

Right - Rigid foam insulation is installed along the exterior edge of an existing foundation slab.

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Concrete slab-on-grade foundation with a turn-down footing insulated on its top surface, showing anchorage of the wall to the foundation for seismic resistance

Concrete slab-on-grade foundation with a turn-down footing insulated on its top surface, showing anchorage of the wall to the foundation for seismic resistance

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Right - Additional potential locations for slab-on-grade insulation include (a) under the slab and outside the perimeter with optional underground moisture block, (b) under the whole foundation, or (c) on top of the slab.

Right - Additional potential locations for slab-on-grade insulation include (a) under the slab and outside the perimeter with optional underground moisture block, (b) under the whole foundation, or (c) on top of the slab.

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Externally insulated post-tensioned concrete slab-on-grade foundation wall with a turn-down footing showing anchorage of the wall to the foundation for seismic resistance

Externally insulated post-tensioned concrete slab-on-grade foundation wall with a turn-down footing showing anchorage of the wall to the foundation for seismic resistance

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Externally insulated post-tensioned concrete slab-on-grade foundation wall with a turn-down footing showing anchorage of the wall to the foundation for seismic resistance

Externally insulated post-tensioned concrete slab-on-grade foundation wall with a turn-down footing showing anchorage of the wall to the foundation for seismic resistance

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Assembly can be used in IECC CZ 3 and above to thermally isolate garages in multifamily row houses with slab foundations. For unheated garages, it is unnecessary to insulate wall between garage and exterior of slab or slab underneath garage.

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Technology Solutions Case Study: Exterior Rigid Foam Insulation at the Edge of a Slab Foundation, Fresno, California

Case Study

Case study describing installation of exterior rigid foam insulation on a slab foundation.

Right - The slab-on-grade foundation is insulated with two layers (R-20) of XPS foam under the-slab and R-10 on the exterior of the stem walls.

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Right – Rigid foam was attached to the tops of the precast foundation walls to form an insulated edge for the floor slab.

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ICF foundation walls wrap the floor slab in R-22 of insulation while the entire space under the slab is covered with 4.3 inches of closed-cell spray foam.

ICF foundation walls wrap the floor slab in R-22 of insulation while the entire space under the slab is covered with 4.3 inches of closed-cell spray foam.

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Spray foam extends down the inside of the foundation wall to the uninsulated slab; because the wall lacked exterior perimeter drainage, the slab was cut and an interior footing drain was installed.

Spray foam extends down the inside of the foundation wall to the uninsulated slab; because the wall lacked exterior perimeter drainage, the slab was cut and an interior footing drain was installed.

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The floor slab is completely insulated with ICF foundation walls and R-20 (3 inches) of closed-cell foam that is sprayed directly onto the ground before pouring the slab.

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Spray foam insulation extends down the foundation wall to the slab, which has been retrofitted by cutting the slab to install drainage mat against the wall and a new perimeter footing drain, along with rigid foam plastic above the slab.

Spray foam insulation extends down the foundation wall to the slab, which has been retrofitted by cutting the slab to install drainage mat against the wall and a new perimeter footing drain, along with rigid foam plastic above the slab.

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Right – Insulated concrete forms (ICFs) provide the insulated stem wall for the slab-on-grade foundation for this SIP house.

Right – Insulated concrete forms (ICFs) provide the insulated stem wall for the slab-on-grade foundation for this SIP house.

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Brick veneer framed wall supported by a concrete slab-on-grade foundation with a turn-down footing insulated on its top surface, showing anchorage of the wall to the foundation for seismic resistance

Brick veneer framed wall supported by a concrete slab-on-grade foundation with a turn-down footing insulated on its top surface, showing anchorage of the wall to the foundation for seismic resistance

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This Texas homes uses a slab foundation including a 4-in.-thick post-tensioned monolithic slab with turned-down edges poured over a 6-mil polyethylene vapor barrier and capillary break; slab edge insulation is not used due to termite risk.

This Texas homes uses a slab foundation including a 4-in.-thick post-tensioned monolithic slab with turned-down edges poured over a 6-mil polyethylene vapor barrier and capillary break; slab edge insulation is not used due to termite risk.

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