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Moisture Control for Residential Buildings

Reference

Report providing extensive guidance on controlling moisture in building envelopes through proper selection and installation on air, water, thermal, and vapor barriers.

READ THIS: Before You Design, Build or Renovate, GM-0602

Reference

Document with important building science considerations, designed for members of the residential construction and remodeling industries, as well as owners and managers who work in affordable housing.

Elevated slab construction with no water sensitive materials on first level

Elevated slab construction with no water sensitive materials on first level

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Saturated ground water

Saturated ground water

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Moisture problems must be dealt with before sealing and insulating a crawlspace

Moisture problems must be dealt with before sealing and insulating a crawlspace

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Right – Foundation drainage mat was installed over the waterproof membrane that covers the sealed crawlspace window

Right – Foundation drainage mat was installed over the waterproof membrane that covers the sealed crawlspace window

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Below-Grade Water Management for Urban Sites

Guide

Guide describing methods to manage groundwater under and around urban multifamily buildings.

Right – A sump pump with a perforated sump pit was installed in the crawlspace slab to reduce water accumulation under the slab

Right – A sump pump with a perforated sump pit was installed in the crawlspace slab to reduce water accumulation under the slab

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An exhaust fan pulls damp air out of a retrofitted sealed crawlspace while drawing in dry air from the living space

An exhaust fan pulls damp air out of a retrofitted sealed crawlspace while drawing in dry air from the living space

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Measure Guideline: Hybrid Foundation Insulation Retrofits

Reference

Document providing information on basement insulation, air sealing and water management retrofits.

Before sealing and insulating the crawlspace, the windows were sealed, the window wells backfilled, and sumps pumps were installed that discharged to the gutter downspouts

Before sealing and insulating the crawlspace, the windows were sealed, the window wells backfilled, and sumps pumps were installed that discharged to the gutter downspouts

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Wrong – This vented crawlspace has standing water because steps were not taken to address site conditions that led to bulk water flow into the crawlspace

Wrong – This vented crawlspace has standing water because steps were not taken to address site conditions that led to bulk water flow into the crawlspace

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Wrong – A poorly sealed window and window well allow bulk water to enter the crawlspace from ground that slopes toward the structure

Wrong – A poorly sealed window and window well allow bulk water to enter the crawlspace from ground that slopes toward the structure

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Water-proof materials cover the exterior side of crawlspace windows in a crawlspace retrofit, while foil-faced rigid foams seals and insulates the inside face of the openings

Water-proof materials cover the exterior side of crawlspace windows in a crawlspace retrofit, while foil-faced rigid foams seals and insulates the inside face of the openings

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Right – Foil-faced insulation was added after the crawlspace was dried and sealed by diverting water runoff, sealing off crawlspace windows and vents, and adding sump pumps and exhaust fan ventilation

Right – Foil-faced insulation was added after the crawlspace was dried and sealed by diverting water runoff, sealing off crawlspace windows and vents, and adding sump pumps and exhaust fan ventilation

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Complete water management strategy for a below-grade wall

Complete water management strategy for a below-grade wall

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Right – This crawlspace window was completely sealed off on the inside and outside with air barrier and water-proof materials and the window well was filled in to an above-grade height to prevent bulk water from entering the crawlspace

Right – This crawlspace window was completely sealed off on the inside and outside with air barrier and water-proof materials and the window well was filled in to an above-grade height to prevent bulk water from entering the crawlspace

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Easy access

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The existing slab is retrofitted with epoxy paint, rigid foam insulation, sleepers (furring strips), and subfloor.

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Concrete Floor Problems, BSI-003

Reference

Information guide describing issues with concrete floors, in multiple climate zones.

The below-grade wall assembly includes dampproofing, draining details, and insulation.

The below-grade wall assembly includes dampproofing, draining details, and insulation.

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

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

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An uninsulated (or existing insulated) basement slab is retrofitted to reduce moisture transmission by sealing with epoxy paint.

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Right - The existing basement slab is retrofitted by installing a dimple plastic drainage mat, rigid foam insulation, and a floating subfloor.

Right - The existing basement slab is retrofitted by installing a dimple plastic drainage mat, rigid foam insulation, and a floating subfloor.

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The existing slab is retrofitted by coating with epoxy paint, then installing rigid foam insulation and a floating subfloor.

The existing slab is retrofitted by coating with epoxy paint, then installing rigid foam insulation and a floating subfloor.

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Taping polyethylene sheeting at interior pier footings

Taping polyethylene sheeting at interior pier footings

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

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

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Rigid insulation and water control layers are installed on the exterior of a flat foundation wall; spray foam insulates the rim joist

Rigid insulation and water control layers are installed on the exterior of a flat foundation wall; spray foam insulates the rim joist

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This exterior wall retrofit permits drying to the exterior of a sill plate installed on an untreated flat foundation wall

This exterior wall retrofit permits drying to the exterior of a sill plate installed on an untreated flat foundation wall

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Bulk Water Control Methods for Foundations, BA-1015

Reference

Report about the fundamental concepts that must be understood at the planning or initial nspection of existing homes regarding surface and ground water management.