Step by Step: Replacing OEM skylights with new Custom Maxim Skylights

[MaximSky]

Joe, I am confident that your skylights will fit. Even if the skylight(s) is larger than the curb by an extreme amount, say 1" overall, if the unit centered, sealed and anchored in the centered position it will be fine.

[MaximSky]

I do believe that removal and replacement of the skylight should not be the main concern vs. using a proper sealant to insure an air and water tight installation. Officially Maxim recommends a neutral cure silicone sealant - Dow Corning 795 - between the roof curb and the bottom of the skylight. But this sealant is not readily available so we also suggest OSI Quad Max. This is also a UV stable sealant that will not fail when exposed to sunlight and can be painted, if one chose to paint the area. If the skylight must be removed, the "peel strength" of sealants is their weak point so pulling up on one corner will literally peel the skylight away. Hope this helps! Thank you all for your comments and support - David (from Maxim)

[carl2591]

do you remember which Sikaflex product you used??. Want to make sure to stay away from that one.

Not sure what AS used on the antenna mount on the roof, but that was a fricken bear to remove. I had 3 sharp chisels and pounded around the edges towards the center for over an hour to get it loose enough to pull off.

sounds like the same devil ...

Originally Posted by Wingeezer

Larry,

However, when I tried to get the old skylight off - no dice!

I tried prying up using plywood to spread the load over the Airstream roof but that Sikaflex just would not give. So I put the screws back in the skylight to think further about the dilemma!


So if I had it to do again, I think I'd be looking for something a little less tenacious than Sikaflex to use when installing Maxim skylights! Not sure what - maybe butyl tape.

Just my experience!

Brian

[carl2591]

good to know about the butyl and heat. Has maxim made any recommendations about what to use for the skylights?.

Seems, as the manf, they would know what are the best products for all types of skylights applications especially with all the airstreams the are now getting their products.

he Sikaflex 715 seem to be a good product, wonder what is the ease of removal if needed.

Originally Posted by asv2

Hello,
I have a new Maxim just installed in April and researched the thread up-and-down before installing, trying to determine what kind of sealant to use.

In Post #200, David at Maxim cautions against using butyl tapes as they have a tendency to ooze. He says heat mixed with contraction and expansion of the polycarbonate may cause the butyl tape to become so hot it will literally melt and therefore render the seal ineffective and possibly become visible from the interior........
Post 134 mentions that David does NOT recommend solvent based sealants as they can attack the skylight components.

I finally settled on Sikaflex 715. (Note there are several different numbered Sikaflex sealants) Sikaflex 715 is not solvent based, but is a "Silane Terminated Polymer" or "STP". Hopefully the Sikaflex 715 will do well.

My Maxim is gray with anodized aluminum frame, looks great! Also, I provided Maxim the exact measurements (22 X 22) and did not add anything. It's a perfect fit.

[Rocinante]

Originally Posted by carl2591

Has maxim made any recommendations about what to use for the skylights?

See post #322 above, I think that's Maxim.

[Wingeezer]

Originally Posted by carl2591

do you remember which Sikaflex product you used??. Want to make sure to stay away from that one.

Not sure what AS used on the antenna mount on the roof, but that was a fricken bear to remove. I had 3 sharp chisels and pounded around the edges towards the center for over an hour to get it loose enough to pull off.

sounds like the same devil ...

It would have been either 221 or 721 - I am not sure which is which, one is on grey that I use around windows etc and the other (I think 721) is white for use on the roof and has additives to make it more UV resistant I believe.

I probably used whatever I had on hand at the time! Those are the only two types I have ever bought.


At the time , I think that I was told at JC that these products, plus Acryl-R were what they used on new trailers including mine, a 2005 Classic 30.

Brian.

[RFP]

Our 2014 23D has its skylight held onto the curb by two-sided tape of some kind. The curb-to-roof flashing sealing looks to be in excellent condition. Question is: Is there any reason to remove what appears to be perfectly good dealing of the curb/flashing before installing a new Maxim skylight? If not, installation will be super quick and easy... I would really like that, it happens so seldom.

[asv2]

Originally Posted by carl2591

good to know about the butyl and heat. Has maxim made any recommendations about what to use for the skylights?.

Seems, as the manf, they would know what are the best products for all types of skylights applications especially with all the airstreams the are now getting their products.

he Sikaflex 715 seem to be a good product, wonder what is the ease of removal if needed.

Hi Carl,
Way back in post #85 Brian/Wingeezer said he used the Sikaflex 721UV. (I printed/made notes of some of the thread before I made my choice!)
David at Maxim did recommend OSI Quad Max. I didn't use only because it's not a sealant I read about in Air Forums, and I reasoned it might not hold up in a moving Airstream application compared to a fixed skylight in a building. It may be a fine sealant for Airstreamers as well. I should have asked David - he was so very helpful and patient with all my questions. They also sent sample colors of the polycarbonate which really helped in picking the right color.

[carl2591]

is this the same stuff..

http://www.amazon.com/Dow-Corning-Si.../dp/B000NY599A

seem like a good product and not all that expensive.

PS i sent a email for pricing and got no response thus far. is it better to call?
unit listed in sig need two.

Originally Posted by MaximSky

I do believe that removal and replacement of the skylight should not be the main concern vs. using a proper sealant to insure an air and water tight installation. Officially Maxim recommends a neutral cure silicone sealant - Dow Corning 795 - between the roof curb and the bottom of the skylight. But this sealant is not readily available so we also suggest OSI Quad Max. This is also a UV stable sealant that will not fail when exposed to sunlight and can be painted, if one chose to paint the area. If the skylight must be removed, the "peel strength" of sealants is their weak point so pulling up on one corner will literally peel the skylight away. Hope this helps! Thank you all for your comments and support - David (from Maxim)

[Florida 55]

McMaster Carr sells Dow Corning 795 sealant in all colors for $8.82 per tube in all colors. McMaster is usually very reasonable for shipping and carries a huge variety of hardware, tools, and industrial products. Also shipping is typically very fast.

Link for Dow Corning 795: http://www.mcmaster.com/#dow-corning...ealants/=12gsf

They also have good prices on Silka sealants: http://www.mcmaster.com/#sika-sealants/=12gsg30

[carl2591]

just got pricing from maxim on 2 skylights for a 2005 classic 31D.

one is $232.00 the other $282.00 that includes shipping. basically one and a half of the OEM tops and never need replacement.

now for it to stop raining so I can get them here and get them on. plus i need to replace the interior trim so another 120 bucks from the pot.. which is running low.

[RFP]

Originally Posted by RFP

OK, maybe this is a dumb question (I'm famous for those!), but wouldn't it be easier to do much of the work in replacing the skylight from inside the trailer? The 'clear' parts of the OEM skylight could be cut out leaving a pretty nice size hole through which to work. Using just a short step ladder, one could stand up through the now-open skylight hole and remove all the vestiges of the original skylight. Also, mount the base assembly of the new one. Then the only work remaining - and that which would have to be done from the roof - is the final installation of the new skylight.

Am I missing something here, or is this a pretty good idea?

Rob

Yesterday, I tackled the job of removing the old skylight and all the Curb-to-roof caulk/sealant. I am super-happy to report that "working from inside the skylight hole" worked out great!

I found it easy and comfortable to stand upright on my crummy little 6' step ladder with the "work" easily accessible. OK, I'm not a very big guy (5'11" and 163 pounds), but there was plenty of room with the old skylight removed... a much larger person could have done what I did and just as easily.

Actually, the hardest part of the job was prying off the old skylight... that darned black two-sided stuff sticks like crazy. I resorted to using a heat gun while prying up with a pry tool (that I can't remember what it's called). I was successful in getting the skylight off unbroken... it's just sitting over the now-open hole as I await the arrival of 3M 4000UV to re-caulk/seal the curb and, of course, my new Maxim skylight.

[Al and Missy]

I found a pair of skylights in the classifieds. Dsaxon22 ordered some based on the "Standard" dimensions and they didn't fit his trailer; thanks Dustin for a great deal!

I was expecting an ordeal to get the old ones off and the curbs cleaned up, but it didn't happen that way. Apparently the PO had replaced the skylights recently and they were just held in place with butyl tape. I pulled them off and, for the most part, the tape just pulled off leaving a clean install surface.



The caulk around the curb had been recently redone as well, so all that was left was to lay a bead of sealant ( I used OSI Quad Max as recommended by David in post 322) purchased at Home Depot. One tube laid a nice thick bead around both curbs.



I set them in place and let them sit overnight.

I got back on the roof this morning and screwed them down with the screws and washers Dustin sent along with the skylights. Thanks again Dustin!







I have the original skylights which are in good shape, still clear, soft, and flexible. One is gray tinted and square at 23.25x23.25 . The other is clear and rectangular at 26.25x18.5. I'll pay Dustin's good deal forward by sending them to the first person who wants them for the shipping charges. PM me if you are interested. They don't weigh anything, so shipping will go by the size, for the most part. I'm located in 32951. The original boxes are 27x27x7 and 30x20x7.

Al

[carl2591]

I can tell you a real quick way to figure out if they are leaking.. remove the two screw on the pull shade on both ends. then remove the two screws on both ends of the plastic trim adn pull it down. now have someone with a water hose spray water on the skylight like it's raining or do this when it raining.

Get a stool and put your head up in there and look with a flashlight to see if you see any water.

I thought mine were fine till I did this and now I am replacing both skylights.

Originally Posted by RFP

Our 2014 23D has its skylight held onto the curb by two-sided tape of some kind. The curb-to-roof flashing sealing looks to be in excellent condition. Question is: Is there any reason to remove what appears to be perfectly good dealing of the curb/flashing before installing a new Maxim skylight? If not, installation will be super quick and easy... I would really like that, it happens so seldom.

[Al and Missy]

I found a pair of skylights in the classifieds. Dsaxon22 ordered some based on the "Standard" dimensions and they didn't fit his trailer; thanks Dustin for a great deal!

I was expecting an ordeal to get the old ones off and the curbs cleaned up, but it didn't happen that way. Apparently the PO had replaced the skylights recently and they were just held in place with butyl tape. I pulled them off and, for the most part, the tape just pulled off leaving a clean install surface.



The caulk around the curb had been recently redone as well, so all that was left was to lay a bead of sealant ( I used OSI Quad Max as recommended by David in post 322) purchased at Home Depot. One tube laid a nice thick bead around both curbs.



I set them in place and let them sit overnight.



I got back on the roof this morning and screwed them down with the screws and washers Dustin sent along with the skylights. Thanks again Dustin!



The first post looked good on my computer. I guess it was finding the links on my machine.

Al

[carl2591]

looks good,,, I went with the white powdercoated as well, which takes a bit longer to get.

My question would be why put screws in top of metal trim and not just around the skirt. you put a nice bead of stuff under there which will most likely hold the top on with no screws.

any time you put a hole on top you create a possible leak path. I was going to just put screws around the skirt, 2 S/S on each side, so any water just drips down the side not inside.

Actually OSI Quad Max is considered a strong adhesive and sealant I bet you can put a nice bead down give in a couple day to set up and not use screws.. less screws, less holes, less place for water to enter.

I am sure someone will come along and say how do you expect it to stay on at 65 MPH when you are going down the road.. Well it appears to me the low profile and curved dome will direct the air over the top not under.

Lewster went to a 3M tape to apply the feet on top of airstream and everyone was all agast. some even put a couple of screws through the tape and then dicor over it all.. have you ever seen a solar panel he installed blow off.. NO.

I am sure someone has seen a panel fly off at some point but not me thus far.

[RFP]

Originally Posted by carl2591

<<< snip >>>

My question would be why put screws in top of metal trim and not just around the skirt. <<< snip >>>

Aren't those "top screws" the ones that Maxim puts there to hold the assembly together? "Factory" screws... from the Maxim factory.

Rob

[Al and Missy]

as RFP said (and I didn't read before posting this) the screws around the top are part of the factory assembly process. I just put screws in the holes in the skirt into the side of the curb.

You are probably right about the adhesive tape being sufficient. The original skylights were held with butyl tape. It came off pretty easily since it was exposed to the sunlight and was pretty hot when I pulled it off. It came off fairly easily but not so easy that wind would lift it, I think. I used the screws because that's what the instructions said to do. "Overkill is just about right", a friend of mine once said.


Al

[rmkrum]

No, the correct phrase is "There is no overkill, there is only 'open fire' and 'time to reload'!"

One of my faves...


Sent from my pocket Internet using Airstream Forums

[TheDuke]

Originally Posted by RFP

Aren't those "top screws" the ones that Maxim puts there to hold the assembly together? "Factory" screws... from the Maxim factory.

Rob

Rob; you are correct. The four screws on top are installed by Maxim. They do have a rubber gasket around each one, however I put a little dab of sealant over each one. I highly recommend installing two screws in each of the pre-drilled holes on all four sides, and cover them with a dab of sealant also.
The Maxims set up higher and have a square frame that has to catch more wind than the factory ones do! If Maxim didn't think it was necessary, I don't think they would punch the holes.