Crawl Space Encapsulation in Pegram, TN

Two rivers in one county means bottomland, and hollows that drain toward bottomland. Air near the rivers and creeks stays heavy through a Tennessee summer, and a vented crawl space sitting in that air never really dries. It breathes the damp in, night after night. The signs are the same on most of the houses we look at here: a musty smell at the floor registers, hardwood that has started to cup, and fibreglass batts hanging down in the low spots where the paper facing gave up.

The other half of the county is hills. East of the Harpeth and south of the Cumberland, the ridges are steep enough that the state has set a large piece of that country aside as the Cheatham State Wildlife Management Area. Houses in that terrain rarely sit on a flat lot. We regularly see crawl spaces that are tall enough to stand in at the front wall and too tight to crawl at the back. The low end is where damp air pools, and it is usually where the original insulation stopped, because it was the hardest place to reach.

Pegram itself is small, a little over two thousand people, and much of the housing in and around town is older stock on block stem walls with open foundation vents. River air, sloped lots and vented crawl spaces is exactly the combination encapsulation was built for.

The vents and the rim come next. Foundation vents get sealed and insulated, because a sealed crawl space only works if you stop treating it like outdoor space. We foam the rim joist and any gaps at the sill line at the same time. That rim is where a lot of the air leakage lives, and sealing it is part of the same visit.

Drainage comes before the liner where groundwater is a factor. If water enters the crawl space after hard rain, a liner on its own just traps it underneath and hides it. In low ground near the bottoms we put in drainage and a sump pump first, then line over the top.

Last is the air. A sealed crawl space still needs dry air, so we either condition it from the house system or, more often in Cheatham County humidity, set a dedicated dehumidifier sized to the space. That unit is what holds the space dry through August.

• Houses on low ground or near creek bottoms. These take on the most moisture and show floor damage first.
• Homes on sloped lots. Uneven clearance means one end stays damp no matter what the weather does outside.
• Older crawl spaces with open vents and fallen fibreglass. Vented is the old way of doing it, and here it does not work.
• Homes with a musty smell or cupped floors. That is crawl space moisture showing up indoors, not a housekeeping problem.
• Homes about to be remodelled. Do the crawl space first, while access is easy and before new floors go over a damp space.

We do crawl spaces every working week, and we stand behind the detail work: pier wraps, the top edge seal, the door or hatch, the drain at the low point. That is where the job is won. If you want to see what a full crawl space encapsulation looks like step by step, that page walks through it.

See our crawl space encapsulation service, our spray foam insulation work, or the full service area.