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Flood-Resistant Raised-Slab Foundations

Guide describing ways to construct a raised-slab foundation to increase a home's resistance to floods.

Slab-on-grade foundation and safe room.

Publication Date

Mon, 03/01/2021 - 12:00

Seismic and Thermal Resistance in Slab-on-Grade Foundations with Turned-Down Footings (Monolithic Slabs)

Guide describing how to construct and retrofit homes built on slab-on-grade foundations in earthquake-prone areas to withstand seismic forces by properly installing wall to foundation connections.

A raised slab foundation elevates the level of the floor above grade

Publication Date

Wed, 08/10/2022 - 12:00

This raised-slab CMU and brick foundation includes flood-resistant features such as a sloped grade, capillary break under the slab (gravel or sand), vapor barrier under the slab (polyethylene sheet), and capillary break at the top of the foundation wall

Publication Date

Sat, 01/01/2022 - 12:00

This raised-slab poured concrete foundation includes flood-resistant features such as a sloped grade, capillary break under the slab (gravel or sand), vapor retarder under the slab (rigid insulation), and capillary break at the top of the foundation wall

Publication Date

Sat, 01/01/2022 - 12:00

Raised-slab CMU foundation including flood-resistant features: sloped grade, damp proofed stem wall, capillary break under the slab (gravel or sand), vapor barrier under the slab and capillary break at the top of the foundation wall (polyethylene sheet)

Publication Date

Sat, 01/01/2022 - 12:00

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

Interior and exterior safe room locations for slab-on-grade foundations.

Publication Date

Mon, 12/01/2014 - 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

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

Right - Flood resistant slab and crawlspace foundations elevate the floor above the design flood elevation.

Publication Date

Wed, 12/01/2010 - 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

The goal of foundation moisture management is to construct the basement, crawlspace, or slab in a way that keeps moisture from getting in in the first place

Publication Date

Thu, 03/01/2012 - 12:00

FORTIFIED Home Eligibility Requirements—Foundations - Eligibility Requirements and Retrofit Requirements for Elevated-Floor (Not Slab-on-Grade) Houses

Author(s)

Insurance Institute for Business and Home Safety

Organization(s)

IBHS

Publication Date

April, 2017

Checklist intending to clarify FORTIFIED Home™ eligibility requirements that relate to a home’s foundation.

A layer of pea gravel or crushed stone, 4 inches thick and sloped 5%, provides a pest-resistant ground break around the perimeter of a slab foundation

Publication Date

Mon, 03/01/2021 - 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 left-to-right sequence shows the method of wall extension to flood-proof a masonry house on a slab foundation. Here the new, raised floor is wood-framed over a wet-floodproofed crawlspace, but using fill to create a new raised slab is also an option.

Publication Date

Wed, 01/01/2014 - 12:00

Brick veneer is supported by a concrete stem wall thermally separated from the slab-on-grade foundation with turn-down footing which is also insulated on top; anchorage for seismic resistance is also shown

A resilient multifamily building in Puerto Rico constructed of concrete on a raised slab foundation with a hip roof design for wind resistance and deep overhangs and permanent awnings to keep sun and rain off windows.

Publication Date

Tue, 01/01/2019 - 12:00

An externally insulated slab-on-grade is pest-protected by a metal termite shield under sill plate, metal-flashing-wrapped foam under siding, a removable inspection strip of PVC-covered foam, and 2 feet of gravel next to the foundation.

Publication Date

Mon, 03/01/2021 - 12:00

Slab Edge Insulation

Guide describing how to insulate slabs on grade in climate zones 3 and higher.

Patio Slabs, Porch Slabs, Walkways, and Driveways Slope Away from House

Guide describing how to correctly slope solid surfaces outside a home so rainwater flows away from the home.

Building Enclosure: Foundation Overview

Termite-Resistant Foundations and Walls

Guide describing techniques and measures for increasing the termite resistance of a home's foundations.

Constructability of Elevating Concrete Slabs on Grade

Publication Date

April, 2019

Author(s)

American Concrete Institute

Organization(s)

ACI

Video from American Concrete Institute explaining the differences between foundation construction strategies and heights to mitigate damage from flooding.

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

Elevated slab construction with no water sensitive materials on first level

Publication Date

Sun, 10/01/2006 - 12:00

Final Grade Slopes Away from Foundation

Guide describing how to properly grade a site so water will flow away from the foundation.

Right – The drain slopes away from the foundation and terminates at the proper distance

Publication Date

Tue, 02/01/2011 - 12:00

Impervious surfaces like patio slabs, sidewalks, and driveways that are within 10 feet of the home should slope away from the house.

This plumbing pipe is wrapped with a stainless steel mesh skirt that is clamped to the pipe before the concrete slab is poured to to keep out bugs and rodents

Publication Date

Mon, 03/01/2021 - 12:00

Pest-Resistant Ground Cover at Foundation Perimeter

Guide describing methods for installing pest-resistant ground cover around foundations to resist borrowing rodents and other pests.

Wrong – Drain pipe has been cut and foundation penetration has not been properly sealed

Publication Date

Tue, 02/01/2011 - 12:00

Flood-Resistant Crawlspace Foundations

Guide describing how to design or retrofit a crawlspace to reduce the risk of damage during a flood event.

Flood-Resistant Pier, Pile, Post, and Column Foundations

Guide describing how to construct flood-resistant homes using pier, pile, post, or column foundations.

Pest protection measures include a termite shield under the rim joist and extending out on either side of the stem wall, insect screening under the furring air gap, and brick veneer to protect slab-edge insulation.

Publication Date

Mon, 03/01/2021 - 12:00

An anchor side plate is used to connect the concrete foundation to the sill plate from the exterior as part of a seismic retrofit when the sill plate is not accessible from the interior of the home

Publication Date

Tue, 08/24/2021 - 12:00

Right – The raised-slab, CMU block stem wall, above-grade walls, and roof of this house use flood damage-resistant materials, integrated water, vapor, and air control layers, and construction methods which promote good drainage and rapid drying

Publication Date

Sat, 01/01/2022 - 12:00

Right – The raised-slab, poured-concrete stem wall, above-grade walls, and roof of this house use flood damage-resistant materials, integrated water, vapor, and air control layers, and construction methods which promote good drainage and rapid drying

Publication Date

Sat, 01/01/2022 - 12:00

Right – The raised-slab, brick-and-block stem wall, above-grade walls, and roof of this house use flood damage-resistant materials, integrated water, vapor, and air control layers, and construction methods which promote good drainage and rapid drying

Publication Date

Sat, 01/01/2022 - 12:00

Good water management practices like sloping grade away from house, and installing gutters, perimeter drain pipe, a capillary break, and free-draining soils or drainage mat protect the foundation from water saturation.

Publication Date

Thu, 03/01/2012 - 12:00

Increase Seismic Resistance and Thermal Performance of Basement, Crawl Space, and Crawl Space with Cripple Wall Foundations

Guide describing different options for providing seismic and thermal resistance for homes with basement foundations, crawlspace foundations, or crawlspace foundations with a "cripple" wall.

Measure Guideline: Guidance on Taped Insulating Sheathing Drainage Planes

Author(s)

Grin Aaron,

Lstiburek Joseph W

Organization(s)

Building Science Corporation,

BSC

Publication Date

September, 2014

Measure Guideline research report providing simple, long term, and durable solutions when using tapes and flashing membranes in conjunction with the exterior face of rigid polymeric foam sheathing to create the drainage plane of a wall system.

Site Drainage Practices to Minimize Localized Flooding

Guide describing steps that builders can take to reduce the likelihood of standing water and localized flooding around the foundation of a home during rainy conditions, with links to several full guides providing detailed instructions for improving water management in new and existing homes.

Back to Basics: Termites and Building Construction

Publication Date

July, 2014

Author(s)

PMP TV

Organization(s)

PMP TV

Video presentation from PMP TV covering different building strategies as they relate to different slab and foundation types and building materials to keep out termites.

West Virginia Stormwater Management and Design Guidance Manual

Organization(s)

West Virginia Department of Environmental Protection

Publication Date

May, 2012

Manual showing how to properly use grass swales to manage excess water runoff.

Poor drainage conditions can enable water to pool around the home.

Wrong – Driveway is not sloped away from the house

Publication Date

Tue, 02/01/2011 - 12:00

Right – Driveway is installed to slope water away from the house

Publication Date

Tue, 02/01/2011 - 12:00

Wrong – The final grade does not slope away from the house

Publication Date

Tue, 02/01/2011 - 12:00

Right – The final grade slopes away from the house

Publication Date

Tue, 02/01/2011 - 12:00

Comprehensive water management features include a capillary break (≥ 6-mil polyethylene sheeting) at all crawlspace floors

Publication Date

Fri, 05/01/2009 - 12:00