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New Charleston, SC home's first level used as parking, storage, and access space

New Charleston, SC home's first level used as parking, storage, and access space

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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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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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Understanding Basements, BSD-103

Reference

Information sheet with methods for constructing or retrofitting basements to reduce moisture issues.

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.

Wrong - Moisture from within the basement foundation wall can migrate into the insulation cavity in a conventional blanket insulation installation.

Wrong - Moisture from within the basement foundation wall can migrate into the insulation cavity in a conventional blanket insulation installation.

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Right - Closed-cell spray foam is used to retrofit an existing rubble basement foundation wall.

Right - Closed-cell spray foam is used to retrofit an existing rubble basement foundation wall.

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Basement Insulation Systems, BA-0202

Reference

Report describing approaches to insulating basements in homes built to meet Energy Star levels of performance of heat loss reduction.

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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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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Drain or Sump Pump Installed in Basements or Crawlspaces

Guide

Guide describing installation of sump pumps in the basement or crawlspace of a home.

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

Guide

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

Flood-Resistant Crawlspace Foundations

Guide

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

Radon Fan

Guide

Guide describing how to install a radon mitigation fan to actively remove radon from the home.