Drywall – Has anyone ever mixed fiberglas strands into drywall mud

drywall

Has anyone mixed 3/8" loose fiberglass strands into drywall mud. I restore boats for a living and we commonly mix these fiberglass strands into the resin to produce a workable paste. This can then be worked with a putty knife. These fiberglass strands are commonly called "chop" and are the same fiberglass which is being put into concrete. I see no reason why they would not reinforce drywall mud also. I am doing some test pieces with 1/2" drywall to determine if this is a good idea or if I am out is left field. Please comment.

Best Answer

In a marine fiberglass-in-resin situation, the resin's surface tension pulls the fibers into the mass, with few protruding fibers. Plus, since the resin is of similar strength to the glass, sanding will remove both fiber and resin at the same rate, leaving a relatively smooth finish.

With strands in drywall mud, however, the mud is likely to leave strands protruding. Plus, if you try and sand it smooth, you'll find that the mud is much weaker than the glass fibers, and you'll inevitably remove more mud than fiber, leaving a "hairy" finish.

People use fiberglass tape or mesh to reinforce the mud, but that only works if, when you're finishing, you only remove some of the mud but never get down to the fiberglass.