Q. My company is in the process of gut rehabbing a house with brick veneer siding. From the interior, we have removed the drywall and wall insulation, exposing 16-gauge steel studs, 24 inches on center. The existing gypsum sheathing is in very poor condition. There is a 3/4-inch air space between the brick veneer and the deteriorated sheathing. Is there any way to replace the sheathing from the interior of the house?

A.Corresponding Editor Paul Fisette responds: Bricks absorb rainwater. Water is driven through the bricks by gravity, capillary suction, vapor pressure, and air pressure. Since the existing gypsum sheathing is wet and deteriorated, it is especially important to maintain the air space between the bricks and the new sheathing, so that any water that penetrates the brick veneer can drain down to weep holes at the bottom of the wall. It is also important to install a layer of #15 or #30 felt over the outside of the sheathing, to protect the wall from future moisture damage.

Replacing the sheathing is an interesting challenge. I can imagine inventive JLC readers everywhere thinking of clever ways to solve this problem. I believe the most effective repair method is to remove the studs in 4-foot sections, and then to insert new pre-assembled wall panels. The panels should have felt attached to the outside. Be sure to provide overlaps of felt at the top, bottom, and sides.