Case Study

Pay me now or pay me later – Crawlspace Case Study

I recently did a crawl space assessment in Pawleys Island, SC. The house was a well-built home constructed in the 1970s. It was built with good materials and it was built to code.

It was built on a typical vented crawl space. The crawlspace vents were upgraded with power ventilators to increase air circulation.There has never been a major plumbing leak. The house was very close to being a tear-down. Now work is beginning to repair major water damage.


Like the crawlspace in your home, this crawlspace is partly below grade. Being below grade, it is naturally cooler than the outside air. Natural convection pulls in the warm, moist air from the outside (accelerated in this house by the power ventilators), draws the air through the floor into the living space, and vents it through the attic – just like a giant chimney. In the summer, if you leave an iced tea glass on your kitchen table, moisture in the warmer surrounding air will condense on the glass, causing it to “sweat”.The exact same thing happened in this crawlspace and could be happening in your crawlspace.


These photographs illustrate exactly how much damage can be done to your home because of condensation. Floor joists and floor underlayment are saturated with water and rotting. Insulation is so saturated and heavy due to condensation that it can’t stay in place and is falling from the floor above. Water is condensing inside the HVAC ducts and they are falling to the floor because of the weight of the water. Water is dripping from all the surfaces in the crawlspace causing puddles on the floor and adding to the humidity.The guys beginning work on this project refer to it as the “rain forest”. Condensation has created so many problems in this house that it will require weeks to fix.


That doesn’t begin to address the significant health hazards of breathing mold and mildew spores and bacteria thriving in this crawlspace.And due to the same convection (the chimney-effect) that has been mentioned elsewhere on this site, those mold and mildew spores and bacteria do make their way into the living space.


Several years ago there was an advertisement for an auto service company that ended with the catchy line, “You can pay me now, or pay me later.” The same thing can be said of this crawlspace.The owner of this home would have been well advised to make a relatively small investment in a crawlspace encapsulation before all this damage ever took place.

The cost of a crawlspace encapsulation is far less than the cost of these repairs.