Green Insulation for Bathrooms
Renovating your bathroom means your walls are probably opened up so it’s a perfect time to:
- check for water damage to existing insulation
- upgrade your insulation
The result will be a healthier and more comfortable bathroom.
Check for Water Damage to Insulation
Water damage can take the form of blackened wood—a sign of mold or rot—or obvious water marks. If you find moldy wood or drywall, contact a mold remediation specialist. Mold is a toxin and can cause severe illness if handled without the proper precautions.
Before replacing water-damaged insulation, locate the cause of the problem and be sure that your new bathroom has been designed to eliminate the moisture build-up in the wall cavity.
Choose High R-Value Insulation that is Resistant to Moisture Build-Up
R-Value is the measure of insulation’s effectiveness at slowing the movement of heat. The higher the R-Value the more effective the insulation. For the bathroom, the best insulation choices are either spray foam or spray cellulose. Fiberglass is a poor choice given its tendency to allow air to flow through it that contains moisture. The adjacent wood and drywall the absorb the moisture which can lead to mold problems. If you are just remodeling the bathroom, it might not be realistic to hire a contractor to spray in cellulose so spray foam is the best option.
See Chapter 6, The Kitchen in the book Green Remodeling for more details.
Review Our Green Kitchen Remodel Best Practices
Insulate for Noise-Reduction
Insulating the walls the separate the bathroom from other rooms in the house has the added benefit of increased sound-proofing. For this purpose, fiberglass is also not the preferred material given that conventional fiberglass batts do not provide much in the way of noise reduction. There are specialized sound reducing fiberglass batts that are often used in sound studios for increased cost.
Install a Vapor Barrier to Prevent Rot
Make sure the insulation stays dry after it’s installed. Water vapor inside the wall can condense when it meets cool outer layers, causing rot and harmful mold growth. A vapor barrier should be installed on the warm side of the insulation. This will prevent moisture from getting into the floor, ceiling and walls.
Reduce Air Leakage with Infiltration Reduction Practices
If you install insulation but leave gaps where air can flow through the wall, you have undone practically the entire benefit of installing the insulation. Be sure, then, to leave no room for air leakage. Use a low-toxic sealant to seal around plumbing fixtures and use foam gaskets behind electrical outlets.