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Exterior Edge Insulation for Existing Foundation Slabs

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

Rigid foam wraps the exterior of the foundation slab.

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

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

Publication Date

January, 2013

Author(s)

University of Minnesota

Organization(s)

ORNL,

Oak Ridge National Laboratory,

University of Minnesota

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

Author(s)

Goldberg Louise F,

Mosiman Garrett

Organization(s)

NorthernSTAR,

NSTAR,

University of Minnesota,

UMN

Publication Date

September, 2015

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

Rigid Foam Insulation Installed over Existing Foundation Slabs

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.

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

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

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

Publication Date

January, 2013

Author(s)

University of Minnesota

Organization(s)

ORNL,

Oak Ridge National Laboratory,

University of Minnesota

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

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

Publication Date

Tue, 01/01/2013 - 12:00

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

Publication Date

Tue, 08/24/2021 - 12:00

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.

Publication Date

Sat, 09/14/2024 - 12:00

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

Publication Date

Tue, 08/24/2021 - 12:00

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

Publication Date

Tue, 08/24/2021 - 12:00

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

Author(s)

IBACOS

Organization(s)

IBACOS

Publication Date

October, 2013

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.

Publication Date

Thu, 09/30/2021 - 12:00

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

Publication Date

Mon, 09/30/2019 - 12:00

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.

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.

Publication Date

Mon, 07/01/2013 - 12:00

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.

Publication Date

Mon, 07/01/2013 - 12:00

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

Publication Date

Thu, 09/30/2021 - 12:00

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

Publication Date

Tue, 08/24/2021 - 12:00

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.

Publication Date

Thu, 09/01/2011 - 12:00

A concrete slab-on-grade foundation with exterior insulation, which can be elevated above the local grade as a flood-prevention strategy.

Publication Date

Tue, 01/01/2013 - 12:00

Spray foam and rigid foam were used under the slab while rigid foam wraps the exterior of the foundation walls.

Right – R-20 of XPS and polyiso rigid foam were added on the slab shelf that is part of this precast foundation wall system.

Publication Date

Mon, 09/30/2019 - 12:00

New Whole-House Solutions Case Study: Exterior Rigid Foam Insulation at the Edge of a Slab Foundation, Fresno, California

Author(s)

IBACOS

Organization(s)

IBACOS

Publication Date

October, 2013

Case study describing application of exterior rigid foam insulation on a foundation system.

Right – The raised slab foundation has a 3-ft stem wall of filled concrete block, then is back-filled with compacted dirt and crushed rock, then insulated with 1” rigid foam covered with taped vapor barrier, under a floor slab.

Publication Date

Mon, 09/30/2019 - 12:00

Spray foam extends down the foundation wall to the slab, which has been retrofitted by adding dimple plastic drainage mat and rigid foam insulation.

Publication Date

Mon, 07/01/2013 - 12:00

Right – After installing the insulated concrete foundation wall panels, the builder installed underslab rigid foam, which was topped by 4 inches of crushed rock then the poured slab.

Publication Date

Mon, 09/30/2019 - 12:00

This exterior insulated slab-on-grade monolithic grade beam foundation is protected from pests by termite shield at the sill plate, borate-treated framing, flashing at end of wall insulation, brick veneer over slab-edge insulation, and rock ground cover.

Publication Date

Mon, 03/01/2021 - 12:00

This assembly can be used to thermally isolate heated or partially heated garages with slab foundations from the exterior in multifamily row houses/townhouses in IECC Climate Zones 3 and higher.

Publication Date

Sat, 09/14/2024 - 12:00

Slab-on-grade with concrete stem wall and slab insulation

Publication Date

Tue, 01/01/2013 - 12:00

Post-tensioned slab-on-grade with exterior and slab insulation

Publication Date

Tue, 01/01/2013 - 12:00

Slab-on-grade with integral grade beam and exterior and slab insulation

Publication Date

Tue, 01/01/2013 - 12:00

Slab-on-grade with masonry stem wall and interior and slab insulation

Publication Date

Tue, 01/01/2013 - 12:00

Slab-on-grade with concrete stem wall and under slab insulation

Publication Date

Tue, 01/01/2013 - 12:00

The basement slab is wrapped in a blanket of insulation including R-27 of closed-cell spray foam under the slab and R-22 ICF blocks wrapping the slab edges.

Slab Happy, BSI-059

Author(s)

Lstiburek Joseph W

Organization(s)

Building Science Corporation,

BSC

Publication Date

April, 2012

How hard can it be to insulate a flat sheet of concrete? I mean you only have three choices – on the top, on the bottom, or on the edge. OK, you might have some combination of the three as well.

Technology Fact Sheet Slab Insulation: Improve Comfort and Save Energy in Homes with Slab-on-Grade Floors

Author(s)

Southface Energy Institute

Organization(s)

DOE

Publication Date

December, 2000

Brochure describing insulation approaches for homes with slab-on-grade floors.

Slab-on-grade termite control techniques

Publication Date

Tue, 01/01/2013 - 12:00

Residential Buildings: Foundations

Author(s)

U.S. Department of Energy

Organization(s)

DOE

Publication Date

August, 2022

Website describing the U.S. Department of Energy's residential buildings program.

Foundation Design Handbook

Author(s)

Carmody John,

Mosiman Garrett,

Handeen Daniel,

Huelman Patrick H,

Christian Jeffrey E

Organization(s)

Oak Ridge National Laboratory,

ORNL,

University of Minnesota

Publication Date

January, 2013

Handbook providing guidance on the design and construction of foundations for homes, including insulation, air sealing, and water management details for basements, crawlspaces, and slabs.

Slab-on-grade with integral grade beam with exterior insulation

Publication Date

Tue, 01/01/2013 - 12:00

Slab-on-grade with concrete masonry stem wall and exterior insulation

Publication Date

Tue, 01/01/2013 - 12:00

Turned down concrete slab - 1 inch rigid insulation

DWG

PDF

Innovation in Frost Protected Shallow Foundations

Author(s)

Green Home Institute

Organization(s)

Green Home Institute

Publication Date

January, 2019

Video describing how a frost-protected shallow foundation (FPSF) is constructed and including use of a stay-in-place EPS (expanded polystyrene) footing form that provides insulation and simplifies the installation of frost-protected monolithic concrete slab foundations.

Innovation in Frost Protected Shallow Foundations

Author(s)

Green Home Institute

Organization(s)

Green Home Institute

Publication Date

January, 2019

Video describing how a frost-protected shallow foundation (FPSF) is constructed and including use of a stay-in-place EPS (expanded polystyrene) footing form that provides insulation and simplifies the installation of frost-protected monolithic concrete slab foundations.

Spray Foam Interior Insulation for Existing Foundation Walls

Guide describing how to insulate an existing foundation wall by adding spray foam insulation to the interior side of the wall.

BSC Information - Slab Edge Insulation for All Climates, Sheet 513

Author(s)

Building Science Corporation

Organization(s)

BSC

Publication Date

May, 2009

Information sheet about insulating slabs.

Turned down concrete slab - 3/4 inch rigid insulation

Right - Potential locations for slab-on-grade stem insulation in new construction: slab insulation should always be underneath, with stem walls insulated (a) inside, (b) outside, (c) not at all, or (d) outside with underground extension to repel moisture.

Publication Date

Tue, 01/01/2013 - 12:00

This house with an insulated slab is protected from pests with a termite shield at the sill plate, borate-treated framing, insect screen covering bottom of furring air gap, and brick veneer over slab-edge insulation

Publication Date

Mon, 03/01/2021 - 12:00

Capillary Break Beneath Slab - Polyethylene Sheeting or Rigid Insulation over Aggregate or Sand and Geotextile Mat

Guide describing how to install a capillary break under a slab foundation using either polyethylene sheeting or rigid insulation installed over aggregate or over sand and geotextile matting.