Crawlspace Contractors Save Money Using the Crawl Curtain
As the old saying goes, “Time is Money.” If you’re a crawlspace contractor, you know that to do a professional crawlspace encapsulation or just install a quality vapor barrier according to expert specifications, it is going to take time. And when you’re paying two or three guys to do the work, anything you can do to save time reduces cost and adds to the bottom line.
YourCrawlSpace has developed a product that can cut hours from a typical crawlspace installation. All of the crawlspace specification writers from the DOE to Advanced Energy to the EPA to the state weatherization offices agree that that properly installing a vapor barrier includes firmly attaching and sealing the vapor barrier to the foundation wall.
The latest DOE standard states, “A continuous vapor retarding ground cover or vapor barrier shall be installed in all enclosed, accessible crawlspaces beneath conditioned space to prevent the diffusion of soil moisture into the dwelling or building materials.” The standard goes on to specify that the vapor barrier be at least 6 mils thick, non-translucent, extend up the walls and piers a minimum of six inches, and be firmly attached and sealed to the perimeter walls and piers.
Attaching and sealing the moisture retarder to the wall can be problematic.
One approach involves using a compressor or a black-powder actuated nail gun. In experiments conducted in our offices, in best cases, black powder nailers blew out a piece of block varying from golf ball to softball size and nearly the thickness of the block face. In worst cases the block was broken in several pieces.
A second approach requires holes be drilled into the foundation wall every two to three feet and the vapor barrier be attached using nylon fasteners. This adds hours to installations and creates fine silica dust, a documented cause of silicosis and lung cancer.
Both methods require one material to seal the vapor barrier to the wall and mechanical fasteners to hold the material in place. The sealant recommended by a number of crawl space encapsulation companies is a two sided butyl adhesive tape. The Tape is expensive. The sealing tape temporarily holds the vapor barrier in place while holes are drilled through the vapor barrier, into the concrete. Plastic fasteners are then forced into the holes to permanently hold the material in place.
While these methods works, we find them problematic in several ways. First of all, they are a multistep installation requiring specialized tools. The companies that use this technique suggest using a hammer drill and a quarter inch masonry bit to drill holes every two to three feet.
Do the math. A 1,800 square foot crawl space will have a minimum perimeter of 170 feet. Drilling a quarter inch hole every two and a half feet will require a total of 68 holes. Drilling 68 holes in concrete is not an easy task and requires four to five minutes per mechanical fastener installation. That totals nearly five hours just to install the mechanical fasteners. While the mechanical fasteners are not expensive – less than $20 for enough to do the crawlspace in the example – hammer drills can be expensive and our crawlspace example would require several masonry bits to do the job.
Even using mechanical fasteners, the state weatherization offices specify that the vapor barrier-to-wall connection be sealed with an expensive butyl adhesive tape or a “non-water-based (solvent-based) exterior grade sealant.” This adds another step, time, and expense to the vapor barrier installation. Furthermore, using solvent-based sealants in an enclosed crawlspace is potentially dangerous, creating toxic and potentially explosive vapors. Deaths due to fires and explosions are documented using these products in enclosed spaces.
A product called the Crawl Curtain was recently granted a patented by YourCrawlSpace. It is a moisture barrier that can be installed to a foundation wall using an inexpensive low VOC adhesive and no mechanical fasteners. The technique both attaches and seals the wall vapor barrier in one simple step. The material has been extensively field-tested by Habitat for Humanity, individual home-owners, and by the ZEBRAlliance, a unit of the DOE’s Oak Ridge Laboratories. The system is competitively priced and material installs safely and easily in a fraction of the time required using mechanical fasteners. A recent customer reports that he installed the wall vapor barrier in his crawlspace in two hours with the help of his son’s Cub Scout Pack – 10-year-olds! It is really that easy.
The recommended adhesive for attaching the Crawl Curtain vapor barrier is a VOC compliant polyurethane construction adhesive. A polyurethane adhesive has several advantages. First, since polyurethane cures (like concrete) rather than dries, it only off-gasses harmless carbon dioxide as it cures. So, it is safe to use in the confined area of a crawlspace. Second, since water is a catalyst for polyurethane to cure, it is the ideal adhesive for use on potentially damp crawlspace foundation walls. A damp wall will even accelerate the curing process.
We’re so confident that you’ll like and use our Crawl Curtain, we’ll sell the first order to licensed contractors at 25% off our normal contractor’s price. Call for details. 877-442-7295.
Your Crawlspace, Inc. pioneered crawlspace encapsulation in the southeast and has been a leader in crawl space vapor barrier innovation nationally. The company has been protecting houses and making homes healthier, safer, and more comfortable for almost a decade. In consultation with the Department of Energy’s Oak Ridge Laboratories, YourCrawlSpace developed a patented encapsulation and vapor barrier system that is cost-effective, durable, safe, and extraordinarily easy to install. The difference is in the wall attachment. The system has undergone extensive testing in our offices as well as in the field by homeowners, in Oak Ridge Laboratory’s ZEBRAlliance project test homes, and by Our Town Habitat for Humanity’s System Vision houses in the Charlotte, NC area. Your Crawlspace sells its vapor barrier system to homeowners, contractors, and wholesalers nationally. All of our materials are made in the USA and Canada.