mobilehomerepair.com

Just brought some used factory standard aluminium trailer windows for my place. Not the greatest but a big step up from the 1979 leaky aluminium ones in there now. My question is caulk or putty tape? Caulk has always worked great but messy. Tape only seems to work with a bead of caulk. These windows will be screwed to the outside of the house. The house has vertical aluminium siding.

Manufacturers installed these windows with putty tape, usually one layer down the sides and bottom and two layers on the top of the window to allow for the ribs in the aluminum siding. Through the years, I have found that actual window leaks were rare. Most calls I get for window leaks were usually roof edge leaks, vents and sometimes the siding.

That being said, caulk would work also. If you use caulk, you might want to use a silicone caulk. Polyurethanes could make it very hard to remove the windows, if that was ever needed, like replacing/repairing windows, or the siding under them.

JMO

both.....

putty tape, and an extra bead of caulk across at least the top of the window, hardly ever leaks.

I have had leaks with putty tape only.

Brenda