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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.

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

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

Publication Date

Wed, 12/01/2010 - 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

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

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.

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.

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.

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.

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

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.

Flood-Resistant Raised-Slab Foundations

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

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

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

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)

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

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.

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.

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

Constructability of Elevating Concrete Slabs on Grade

Elevated slab construction with no water sensitive materials on first level

Final Grade Slopes Away from Foundation

Flood-Resistant Crawlspace Foundations

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

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

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

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

Site Drainage Practices to Minimize Localized Flooding

Design and Retrofit for Flood Protection

Flooding Overview

Swales, Drains, and Site Grading for Stormwater Control

Fuel Tanks Anchored for Disaster Resistance