How to clean inside storm windows

[nielloeb]

For picture storm windows (those screwed on outside a non-opening window) which have become hazy inside, is this right?

1. Have a partner. 4x6 windows are heavy.
2. Unscrew the screws, holding the window in place while you do the last ones.

3a. Take the window off. 3b. Pry the window off carefully if it's stuck, without bending any of the metal.

1. Clean the window. Make sure it's dry so you don't introduce moisture inside.

5a. If the window used felt around the edges, make sure it's in good shape or replace it. 5b. If the window used felt around the edges, consider taking it off and using caulk, for felt could be the reason the window got dirty on the inside in the first place. 5c. If the window used caulk, remove the old caulk and use a fat bead of butyl or elastomeric caulk on the casing. (Do not use silicone, which makes future repairs or replacement more difficult.) 5d. If the bottom was caulked, be sure to not put it where there are weep holes in the bottom. 6a. Replace the window and screw it in. 6b. If any of the screws don't go in straight, or all the way, as can happen with projects like this, remove each of those screws, put caulk in the hole, then replace the screw. This will prevent air and water from going where it shouldn't, causing you to have to clean the window again sooner.

[Don Young]

I believe I would use felt rather than caulk to seal an inside window since it does not have to be watertight. No matter how you seal the window joint you can not and should not make the entire space air-tight since that could cause damage from the air pressure. Lack of venting can also cause condensation problems. As far as I know, all storm windows have vents of some kind.

Don Young

[Bob F]

I would not consider using caulk. If you do, you'll probably never be able to remove it again, and it will need cleaning again, no matter what you do.

Even sealed doublepane glass fogs up if any defect occurs.