Replacing Skylights - Screw Type Needed

[dlewand53]

I am going to be replacing both the living area and bathroom skylights. As I have read about the replacement on line I have never seen any description for the screw type. One site said to reuse screws and I don't want to do that. However I want to have the new screws already purchased so available when I install the skylights. So, what type of screw should be used? What size? What length? Appreciate any feedback.

[donniedu]

Likely a 3/4 inch long square head. If your replacing them then get SS pan head screws in either 3/4 or 1 inch long.

[Restcure]

I suggest you count all of the screws you're going to need, then remove one from the skylight and take it to your local hardware store for a match.

I'm curious... is there a particular reason you don't want to reuse the screws?

[dlewand53]

My experience has been rusty or the head snaps off when put in again. Want to be sure I am using a non rusting type of screw.

[Petersb]

I would definitely use stainless screws they are not supposed to rust

[mudman2]

Just a thought. U may want to forgoe screws and caulk it down and then Eternabond which you’ll probably have to do down the line anyway. I have a aframe with skylights where one has a crack in the corner of the flange. I’m going to Eternabond it an hope it works.
Everybody says it’s the greatest thing since sliced bread.
We’ll see.

[jimmoore13]

I agree that removing a single screw for a sample would be worth the effort. Plus you may discover that the screws are in great condition. But, they may well be aluminum...not steel. If so, be sure to use a square drive bit rather than Phillips, or you may strip the head. Many RV screws are both Phillips and square drive, which makes it much easier for the assemblers who are using power tools to drive screws with a square drive bit.

If you remove a sample, some regular household caulk will seal the hole temporarily.

If you buy new screws, definitely replace with stainless. Stainless is compatible with aluminum (skylight frame, framing structure, etc.), and they are both stronger and won't corrode.

If any of the screw holes are enlarged, the new screws may not hold well. In that case, or if you have issues with screws vibrating loose on washboard roads, etc., I recommend using Gorilla Glue in the holes and on the threads. This glue bonds to metal and many other materials, and it will thoroughly seal the hole to prevent water chasing down the screw threads in the event of a caulking failure. Bear in mind, however, that Gorilla Glue is STRONG. It might be very hard to remove the screws next time you replace the skylights. Alternatively, you can buy one size larger stainless screws, e.g. #8 instead of #6 and so on.

[NMWildcat]

When I replaced all my skylights, the new screw holes didn't line up and there were more required for the new ones. They were all 1" self tappers. Get some skylight caulk ( yes they make it) and use it around the opening before placing. Then screw it in firmly, but not enough to distort plastic, then eternabond it. Hardest part is cleaning up the old caulk

[Fkrel]

When I replaced the roof on my class A I replaced the skylight I had to drill new holes in the skylight so I spaced them so it was making a new hole in the motorhome also and put buytal tape under the skylight edge after mounting I used dicor self leveling caulk it came out great. Here is a place I orderd a lexan skylight lexan is alot tougher than the usual plexi skylights. RV Skylights, Square, Rectangular & Round.

[MacGumbo]

Originally Posted by Petersb

I would definitely use stainless screws they are not supposed to rust

Actually they can rust, albeit very slow on their own and usually you can clean it off, hence the "stainless" label.