FOR PROS
Business tools custom-built for our industry

Say 'so long' to generic business software. Houzz Pro is designed for industry professionals like you.

webuser_819138824

MLV on inside of exterior walls, good or bad??

Joe Mon
January 9, 2020
last modified: January 9, 2020

Hello, I am trying to find an answer to a recent home “improvement” that I made. I own a brick veneer home near Baltimore MD that was built in the early 60’s

I recently gutted a bedroom that had backed fiberglass insulation and wood paneling. i discovered that I have black fiber board sheathing. Everything looked great when I replaced the insulation with rock wool. I noticed that someone put a hole in the sheathing when installing an outlet box and covered it with felt paper. I don’t know if the house is wrapped in felt paper or they just covered the hole.

Before installing rockwool, I caulked all the joints and sealed all gaps and openings around windows. I even wrapped the outlet boxes with fire retardant putty. I then covered the rockwool with sheets of MLV using roofing nails and taping all seams. I then applied one layer of 3/8” drywall and caulked all joints. I then used green glue and installed a second layer of 3/8” drywall, making sure to overlap joints and I caulked around all outlet boxes.

My concern is that I may develop mold or rot within the wall because of the MLV sheets. I am planning to update another room soon and don’t want to make the same mistake.

Comments (14)

Need help with an existing Houzz order? Call 1-800-368-4268