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crawlspace case study


Application Case Study: Crawlspace Insulation Renovation    


The Problem:


The Village at Fox Point is a 56 building, 450-unit housing project originally constructed

in 1949. The buildings and individual units were heated until the 1980’s by steam

generated from a central plant and distributed through underground pipes. During this

time period, sufficient heat escaped from the steam pipes, located in the crawlspaces,

to prevent the plumbing pipes from freezing during the winter months. When steam was

eliminated in the late 1980’s and individual heat and cooling units installed, plumbing

pipes located in the crawlspace began to freeze and break during the winter months.


To correct the situation, heaters were installed in the crawlspaces and operated during

the cold months. Over time, The Village at Fox Point fell into disrepair and became a

problem within the Wilmington Delaware community. In 1995, the property was purchased by owners who planned to renovate the complex and create mid-priced rental units. Once the first renovated units became occupied, the new tenants began to complain about “sick building issues” cold drafts, high heating bills, and began to move out. An inspection of the crawlspaces found that there was no insulation. Of further concern in the crawlspaces was the discovery of mold on the underside of the floorboards. A program to insulate the crawlspaces with fiberglass was implemented but was quickly found to be impractical and incapable of creating an effective air barrier. The fiberglass insulation program did not correct the tenant complaints of cold drafty floors, high heating bills, or poor indoor air quality that originated from the moldy crawlspace area.The new owners

of the property began searching for an insulation and air barrier solution that would

address the issues raised by the tenants, eliminate the need for and costs associated

with the winter crawlspace heaters and address the mold situation within the
crawlspaces of the buildings.

The Solution:


Thermal Seal Experts undertook the task of insulating and air sealing the crawlspaces

of various units within the complex with open cell spray foam insulation by:

  • Installing 3 inches of spray foam insulation directly onto the underside of the floor-

boards. This insulation, with its air barrier properties, blocked the warm air of the living

space from coming into contact with the cooler crawlspace, thus preventing condensation

and resulting mold while providing the tenants with comfortable floor temperatures. The Icynene® also encapsulated any dormant mold spores, depriving them of the air and moisture required for sustenance.

  • Installing 3 inches of spray foam insulation directly onto the concrete walls of the crawlspace and covering the area

to 3 feet below the ground line. This procedure minimized any conductive heat transfer in the space and prevented air leakage from the above grade exterior.


The Results:

The crawlspace heaters were turned off and the temperature remained well above freezing even during the coldest December nights in the buildings that had spray foam insulation installed (temperature testing and monitoring conducted by Furlow Associates). There were no frozen plumbing pipes. Eliminating the crawlspace heaters will save the owners $700,000 over 10 years in equipment, maintenance and operating costs. (Data provided by Furlow Associates and Mr. Bill Bennett, Maintenance Supervisor – Village at Fox Point) Tenants noticed an immediate improvement in floor temperature and elimination of cold drafts. They also noticed an immediate improvement in their indoor air quality as the musty odors of the crawlspace were blocked from entering the living space located above. The occupant, at 1249 Kynlyn Drive, reduced his gas consumption in December 2000 versus December 1999 by 15% due to the installation of spray foam insulation in his crawlspace. This decrease was achieved even though December 2000 had an average temperature 25% colder than December 1999. Without spray foam insulation in the crawlspace, the projected gas consumption for December 2000 would have been 14% higher than December 1999. In equalizing the temperature to the December 1999 level, spray foam in the crawlspace effectively reduced the gas consumption of 1249 Kynlyn Drive by 29%. Air leakage through the building envelope had been identified as a major contributor to energy inefficiency. Insulating and air sealing the crawlspaces of one tested building within The Village at Fox Point with spray foam insulation reduced the air leakage of the entire structure by 56% (Testing conducted by Energy Services Group). Based on the success of the spray foam insulation in addressing the concerns of the tenants and owners, Thermal Seal Experts were requested to renovate the remaining buildings within the complex.


The Insulation Renovation:

√ Reduced gas consumption & saved money – a 29% reduction in gas consumption

√ Allowed for the elimination of extra heating equipment costs totaling $700,000.00

√ Was a key element in the mold remediation program

√ Improved the indoor air quality for tenants by providing an air barrier between the musty air of the crawlspace and the living

    space located above.

√ Provided tenants with a more comfortable living environment, thereby assisting in the reduction of tenant turnover.

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