I haven't been up there for about 6 or 7 mos. Didn't notice it then, but I wasn't looking either. It makes me wonder if it's been there all along for 5 years, but due to the tint of the plastic, I just never noticed it. It's just been sitting in the drive way since Oct. Anyway, recommendations? Do I pressure test it before going to the trouble of replacing it? If it doesn't blow bubbles, should I go ahead and Dicor over it and seal it up? Or get a new one and check for water damage? We did have some significant rain over the last couple months, so there's that. I sprayed some water on the crack,but it didn't suck it or seep in. :h

They get stiffer and weaker over time and finally the flex breaks the plastic.My thought is why take a chance. They aren't horribly expensive, they're not horrible to replace, and if you do have water damage, it would be good to find out before it becomes a horrible experience. JMO of course.

I had this happen on my AF. I could see the water in it from the inside. I took it off and separated the two halves to clean out the water.Put it back on, sealing the two halves with Dicor. I reinstalled it with the screws going through some 1" 18 gage metal banding to help spread the pressure and then sealed the outside, high enough up on the plastic to cover the crack. No problems now for 4 or 5 years.I found a new skylight back then for I think around $140. Never did order it.

UV light causes that plastic to harden and become brittle and then break up. Once the cracks start, it won’t be long until it just crumbles. Replace it. Might as well do that now and be done with it. You will have no choice in the matter soon anyway.

Judging from the size of the cracks, I bet you have water issues underneath. I'd remove it as well and see and if minor replace it with anew one. They are cheap.

Okay, so I pulled the interior trim and there are small cracks in 3 corners. Definitely needs replacing. Doesn't appear to be any water damage--that I can see, other than this discoloration. What's it made of anyway, lexan? Do they make them in a longer-lasting material? Fiberglass? I don't stand in the shower anyway. I spend as little time in there as possible. I don't need to be comfortable. I just assume forgo the skylight, screw a piece of metal down, dicor it, paint it white and call it good.

Do Skylights Just crack? | Good Sam Community

joeshmoe
Explorer
Mar 25, 2019
Thanks for the replies.

In researching, I discovered that using regular Dicor is a no-no on Lexan. "May cause material to crack". Well, That's what I used last year and that's what happened. Didn't know. Oh well.
Bird_Freak
Explorer II
Mar 23, 2019
rhagfo wrote:
MFL wrote:
I agree, you need to replace yours, rather than trying to repair. I have noticed the UV rays tend to harden the plastic/lexan over time. While it is too late in this case, I have found that using Protect All on mine, a couple times a year, and wiping with 303 between times, seems to keep it more soft and pliable.

Jerry

The other thing to do once replaced, is to install vent covers. We replaced the original on our 5er with some inexpensive Camco covers about three years ago. Well we lost one in a strong wind storm this last winter, so replaced it and one other (Cracked) with MaxxAir covers then. About a month later we lost one of the remaining Camco covers in another wind storm, so replaced the remaining two. The MaxxAir have a six year warranty.

MaxxAir Vent Cover
I have never seen a vent cover for a skylight but you do need to replace that one. Mine cracked last year and I was lucky it only leaked in the shower. I got mine from Amazon.
map40
Explorer
Mar 23, 2019
I have several RVs, they all always crack. What I do is as soon as I buy the RV I put a really heavy coat of through-the-roof over it (1/4 or 1/3 in). It is a great sealant, transparent, and gives extra UV protection. Never had to change them again.
rhagfo
Explorer III
Mar 23, 2019
MFL wrote:
I agree, you need to replace yours, rather than trying to repair. I have noticed the UV rays tend to harden the plastic/lexan over time. While it is too late in this case, I have found that using Protect All on mine, a couple times a year, and wiping with 303 between times, seems to keep it more soft and pliable.

Jerry

The other thing to do once replaced, is to install vent covers. We replaced the original on our 5er with some inexpensive Camco covers about three years ago. Well we lost one in a strong wind storm this last winter, so replaced it and one other (Cracked) with MaxxAir covers then. About a month later we lost one of the remaining Camco covers in another wind storm, so replaced the remaining two. The MaxxAir have a six year warranty.

MaxxAir Vent Cover
Richmcm
Explorer
Mar 23, 2019
Had to replace our shower skylight last year. Cracked developed last winter. Old and cold caused it. Purchase a new one from Winnebago. Easy installation. Used a multi tool to remove the old sealer.
MFL
Nomad II
Mar 23, 2019
I agree, you need to replace yours, rather than trying to repair. I have noticed the UV rays tend to harden the plastic/lexan over time. While it is too late in this case, I have found that using Protect All on mine, a couple times a year, and wiping with 303 between times, seems to keep it more soft and pliable.

Jerry
garyemunson
Explorer II
Mar 23, 2019
As for covering it with metal, it won't be that much more expensive to replace it like it was. Life changes and down the road you may find you need/want to sell the RV. A cobbled up repair like you are contemplating may well drive off potential purchasers. I'm a fan of doing things right.
joeshmoe
Explorer
Mar 23, 2019
Okay, so I pulled the interior trim and there are small cracks in 3 corners. Definitely needs replacing. Doesn't appear to be any water damage--that I can see, other than this discoloration.

What's it made of anyway, lexan? Do they make them in a longer-lasting material? Fiberglass?

I don't stand in the shower anyway. I spend as little time in there as possible. I don't need to be comfortable. I just assume forgo the skylight, screw a piece of metal down, dicor it, paint it white and call it good.
SidecarFlip
Explorer III
Mar 23, 2019
Judging from the size of the cracks, I bet you have water issues underneath. I'd remove it as well and see and if minor replace it with anew one. They are cheap.
naturist
Nomad
Mar 22, 2019
UV light causes that plastic to harden and become brittle and then break up. Once the cracks start, it won’t be long until it just crumbles. Replace it. Might as well do that now and be done with it. You will have no choice in the matter soon anyway.

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