I understand the physical differences in the two types of spray foam insulation, but does one have any real tangible practical differences other that wicking properties? Is there a difference in cost?
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story

Listeners write in about fire-rated doors, using seven minisplits for cooling, and how to build a second-story addition.
Highlights
Fine Homebuilding Magazine
- Home Group
- Antique Trader
- Arts & Crafts Homes
- Bank Note Reporter
- Cabin Life
- Cuisine at Home
- Fine Gardening
- Fine Woodworking
- Green Building Advisor
- Garden Gate
- Horticulture
- Keep Craft Alive
- Log Home Living
- Military Trader/Vehicles
- Numismatic News
- Numismaster
- Old Cars Weekly
- Old House Journal
- Period Homes
- Popular Woodworking
- Script
- ShopNotes
- Sports Collectors Digest
- Threads
- Timber Home Living
- Traditional Building
- Woodsmith
- World Coin News
- Writer's Digest
Replies
There's a big difference in density (0.5# vs 2#-3#), which can make one useful where the other isn't, and vica versa. There are differences in the rates at which air and water vapor pass through, too.