DIY Crawl Space Encapsulation on a Budget: Day 1 - Seal Vents

After a musty smell began to work itself up from the crawl space and into our home, we knew that something had to be done. We got estimates from three reputable companies that specialized in crawl space repair. Prices ranged from 5-8k. While we weren't happy about the expense, we were especially frustrated that each company had very different recommendations. After spending countless hours researching the problem and various solutions, I decided that I'd just take care of it myself. I am going to publish my progress so that others may benefit from my experience.

Gear:

• Petzl E91 Tikkina 2 Headlamp
• Hard hat
• Safety goggles
• 3M 6000 Series Half Facepiece Respirator, Medium
• Long-sleeved t-shirt
• Jeans
• Kneepads
• Rain boots 

I only needed to see what I was looking at, so a headlamp was sufficient. The hardhat was a must because we have nails sticking out all over the ceiling of the crawl space. I only wore the safety goggles when using Great Stuff. I used a good respirator because it is musty in the crawl space and I am going to be working in the dirt after I remove the current vapor barrier.  I wore long sleeves and jeans because it's a dirty job. The kneepads made the job much more pleasant since I spent most of my time crawling. Finally, I wore my rain boots because they could be easily hosed off.

Supplies:

• Pactiv Extruded Polystyrene Foam Board Insulation (Common: 1-in x 4-ft x 8-ft; Actual: 1-in x 4-ft x 8-ft) 
• Flat black Rustoleum 
• Great Stuff Insulating Foam Sealant

I purchased 1 sheet of foam board from Lowe's and spray painted one side with flat black Rustoleum. From inside the crawl space, I started at one end and made my way around removing screens and vent fans and noting the dimensions of each opening.

As I made my way to the back of the house, there were several unique circumstances. One opening was covered with plumbing including a drain line from the water heater that exits the home through the crawl space vent. The other unusual opening was partially covered with an extra floor support that prevented me from being able to remove the current vent screen from inside the crawl space. 

After getting measurements, I went outside and cut the foam board with a retractable utility knife and labeled each one. Before going back under the house, I sealed the two previously mentioned openings from the exterior. Despite taking measurements first, nearly every piece of precut foam board had to be trimmed. After fitting it in the opening, I sealed it with Great Stuff insulating foam sealant.

It turns out that Great Stuff is a mess! I should have practiced using it in the crawl space. Instead, my first disaster is clearly visible for all to see. I am still not sure how I will clean it up, but I am sure that it is sealed.

Most of the openings had two screens, one inside and one mounted outside. As mentioned earlier, I removed all of the interior screens that I could access, but I left all of the exterior screens. From the exterior, the foam board is completely unnoticeable.

Unfortunately, one opening does not have an exterior screen, and of course that is the opening with Great Stuff smeared all over it. I don't expect the black painted foam board to last forever, but I do think that it will last long enough until I can afford to purchase vent covers that can be easily installed over the openings. Eventually I will get something like this for all seven openings: Large Outward Mounted Vent Cover (13" x 21")