We had some water damage in our home's second floor laundry room because the drip pan, which sits under the W & D overflowed. The drain line in the drip pan failed somehow, so after the water filled up the drip pan, it overflowed, eventually soaking through to the lower level. Do I need to replace sheetrock, plywood, or insulation that got wet, but is now dry? Also, what are my options for a floor drain in the laundry room to prevent this from happening again? Thanks for your time.
Darcy ~ North Carolina
Hi Darcy. Second floor laundry rooms can be convenient, but when there's a problem, it can be much more costly than when the room is located on the main or basement level of a home. If the leak was large enough to come through to the level below, the sheetrock, insulation, and plywood were most likely thoroughly saturated. Even though everything appears to be dry now, there is a good chance that there is still lingering moisture that isn't visible.
My suggestion would be to remove any sheetrock that was saturated and allow the exposed area to completely dry. Any insulation in the walls or floor that was affected should be thrown away and new material installed when drying is complete. While the sheetrock might seem to be dry, there's a good chance that water stains may remain and be difficult to cover with paint. I don't think you should have a problem with the plywood.
The primary reason for replacing the sheetrock and insulation is that any lingering moisture may cause mold to start growing and if it continues without being seen, you could have a large and somewhat expensive problem. This is a concern anywhere, but especially in a state prone to high humidity such as North Carolina.
If local plumbing code allows, a floor drain could be installed in the room that contains your washer/dryer, but I don't think it will do much good. Floor drains work best when the floor area around the drain slopes to allow the water to run to the grate and this isn't possible with a plywood floor. My suggestion would be to run another drain pipe from the drip pan to your main washer drain line or to an exterior wall so there's an emergency backup if the main line becomes clogged. The line to an exterior wall would be similar to the emergency backup systems installed for attic AC condensate lines which alert you to a problem before water is dripping through the ceiling.
I would contact a local contractor that specializes in plumbing repairs and ask them to take a look at the situation. They should be able to give you the most economical solution to your problem.