We’ve tested dozens of methods and products to bring you this focused guide on getting the perfect seal with crawl space vapor barrier tape.
Recommended Tapes
Zip System Flashing Tape - For concrete adhesion and pier wrapping
Vapor Barrier Seam Tape - For joining vapor barrier sections
Duct Tape - For temporary positioning only
Preparation
Clean all concrete surfaces with a brush to remove dust before applying tape
Cut tape pieces to size before going into the crawl space
Have a roller tool ready to press tape firmly against surfaces
Taping Techniques
Wall-to-Vapor Barrier Connections
Position vapor barrier against wall using temporary duct tape
Apply Zip System flashing tape along the entire seam
Use a roller to firmly press tape onto concrete for proper adhesion
Vapor Barrier Seams
Overlap vapor barrier sections by 6-8 inches minimum
Apply vapor barrier seam tape along the entire length of overlaps
Press firmly to ensure no gaps or wrinkles
Pier/Column Wrapping
Brush dust off concrete piers
Cut vapor barrier with extra material for wrapping
Wrap piers “like a Christmas present,” cutting notches as needed
Secure with Zip System flashing tape around the entire perimeter
Use roller to press tape firmly against concrete
High-Traffic Areas
Install vapor barrier stakes before taping in step areas
Apply additional tape over stakes to prevent tripping hazards
Tips for Success
Work from the furthest point inward to avoid crawling over completed sections
Ensure no gaps in tape application anywhere
For sealed crawl spaces, use Zip tape and spray foam around all vents
Apply tape in straight, even lines for best appearance and function
Choosing the Right Tape for Your Project
Before installing your vapor barrier tape, it’s important to select the correct type for your application. Different colored tapes serve specific purposes in vapor barrier systems. Learn whether red or blue Tuck Tape is appropriate for your project in our detailed comparison: Red vs. Blue Tuck Tape for Vapor Barriers
Calculate Your Tape Requirements
Running out of tape mid-installation can delay your project and create unnecessary seams. Ensure you purchase the right amount of both seam tape and butyl tape based on your crawl space dimensions with our helpful guide: How Much Tape to Buy for Vapor Barrier Installation