Chinook RV

Recently I’ve installed new roof vents in our Chinook and used roofing tiles to seal the floor of the vacant generator cabinet. This provided serendipitous training for the present home saga.

‘She who must be obeyed’ insisted the leaking home skylight get fixed before Christmas but local roofing contractors were of dubious reliability. No problem, thinks I - should just be a bigger version of my Chinook projects.

Home Depot sourced a nice new double-glazed Velux skylight for me to replace the existing plastic bubble and there was no more excuse to procrastinate. I pried off shingles down to particle board and prepared the 4’ x 2’ opening. Naturally the only rain in months was forecast that evening to increase my stress factor.

The tricky part was stair-stepping new shingles to fit the ragged opening with sufficient overlap for a leak-proof seal. To this end I applied roofing tar in vast quantities and naturally created a heinous mess on clothes and tools. My timid “Honey, I have some items for the laundry….” was not well received.

Anyway, to conclude with some relevance I want to mention a possible alternative to butyl tape for sealing water leaks through the Chinook’s shell. It is Velux adhesive underlayment for skylight and Google will provide more details. This comes in rolls and is very durable plastic sheet with a pre-applied and incredibly tacky tar adhesive layer.

If tar was good enough for the Royal Navy’s sailing ships then the Chinook should also benefit from this more natural and proven material.

I took a look and I may be wrong but I think the Velux product is only adhesive on one side (which makes sense as it is an alternative type of flashing).

The butyl "tape" we are speaking of is not really tape. It's just called that because it comes on a roll, I'm guessing. What it is is butyl rubber in a strip shape. There is unattached paper between the layers on the roll but once you peel that off it's just the same butyl on all sides. Very, very stretchy and tacky. You can easily roll it into a worm, ball, or whatever shape - not just the tape-like shape it comes off the roll in. It's just basically like a sticky rubbery type thing. There isn't a non-sticky side (like you'd think due to the name "tape").

There is a product called Eternabond which is (maybe? I think?) some form of butyl but with a non-sticky skin on one side.

I can't really see a "normal" use on the Chinook though, because when we are bedding items the bedding (butyl or whatever) is going under the flange of the vent/window/whatever and not on top. With the fiberglass shell, we have a good base to bed to.

I have seen it used on Class C's that have sheet metal or other roofs with seams. Since you can't really take the seams apart to seal them as they were originally, you kind of throw in the towel and put a layer of the Eternabond tape over the top of the seams. I have also seen people put it around the edges of a Fantastic Vent, kind of like a band-aid. It's hard to remove though (unlike the butyl tape we're speaking of, which removes with mineral spirits).

Glad you got the skylight done before it rained. Doesn't it just frost you when you live in a climate where it rains like 4" per year and then it threatens to rain on that ONE day you don't want it too? Sheesh.