Desired Outcome:
Durable, effective vapor barrier minimizing moisture migration into living space.
Vapor barrier completely covers dirt floor with sealed seams and is secured to the foundation.
Before
After
Steps
- Remove debris
This includes biodegradable matter and sharp objects.
2. Layout vapor barrier
Leave enough material to run up the foundation walls and overlap the seams.
3. Use reinforced barrier in traffic areas
In traffic areas it is required to use a crossed-linked or reinforced barrier.
If foundation shows signs of moisture wicking, consider installing the vapor barrier 6 inches above adjacent ground level
4. Attach the vapor barrier
Use one of the following options 4a or 4b to attach the barrier to the foundation
4a. Option 1: attach & seal w/ furring strips & caulk
Secure perimeter of the vapor barrier to the foundation at least 6" above interior grade.
Wrap the barrier around the furring strip two times
Secure to foundation with masonry fasteners. Caulk along the top of the barrier to seal it to the foundation.
4b. Option 2: attach & seal w/ butyl tape
Secure perimeter of the vapor barrier to the foundation at least 6" above interior grade.
Clean off the foundation and apply the tape to the walls.
Use weighted roller or other tool to attach the barrier to the tape.
5. Seal seams
Vapor barrier seams will overlap at least 12 inches and be sealed with Butyl tape, or other adhesive that will cure when applied.
Caulk won't cure and cannot be used to seal seams.
6. Attach & seal to masonry piers
Fasten and seal the barrier to all masonry piers.
7. Leave gap between wood and barrier
Cut barrier 1" to 2" short of any wood post or framing member that extends to the ground.
8. Stake down barrier
Stake the barrier to the ground in traffic areas and around edges of wood penetrations.
Install tape over the top of each stake.
9. Client Ed
Educate the client on things they can do to extend the life of the vapor barrier.