I spent all day yesterday refitting a roof-light on a caravan that we recently purchased. Like you said, it lifted straight out, as the bonding had not adhered to the smooth surface of moulding. I roughed it up with sand paper and refitted it with a whole tube of CT1. If it leaks again I’ll blow the whole caravan up.
I’ve just fitted a new roof light to our old Sterling caravan after the plastic support struts on the original began to disintegrate. Good tip about sanding the sealing surface. Thankfully I’d already done that; it’s only the narrow flat rim that needs sealant, though.
Hi Rick, Had exactly the same with the 2 I installed, same ones as you have MPK;s, I stuck them in with Stixall and leaked after 5 months, after taking them out I used wire wool to key the surfaces and cleaned then re-stuck them back in with Stixall and still going strong with no leaks, touch wood! Glad you got it sorted :) Andy
Couldn't believe we had the same problem and your info helped enormously thank you!! We cut around the sealant that we had only laid a few months ago on the roof side and literally my Dad just pushed up the roof light as to open it so to speak and it just popped out of the sealant, you couldn't make it up! We roughed up the seat in the new roof light, cleaned it with alcohol and washed the blinkin' thing for good measure as you said with fairy, dried with a hairdryer and put it all back together again with "Soudal Fix All High Tack Polymer Adhesive & Sealant"! Hopefully that will be the end of it!! Cheers Rick!!
Hi folks! As promised, here is the video about why my rooflight leaked. Note: Mastic used was: Sikaflex 512 :) Hope it helps others to not have the same problems :)
My fantastic fan rooflight has a small leak in one corner that only leaks when it rains not when there is standing water against much of the seals, its driving my potty I don't understand why its leaking or how to fix it!
THANK YOU !!!!! I replaced both the skylights in my vintage Hymer van some months ago but last week one of them started leaking. I was on the roof yesterday checking it and the sealant could be seen all the way round - so why the leak? I searched on RU-vid and found your video so unscrewed mine to check the adhesion. And lo and behold - it lifted cleanly and easily off the roof, leaving the Sikaflex firmly attached to the roof but the skylight ( exactly the same as yours ) was clean as a whistle. So I'm waiting for it to dry after washing it in soapy water, then with vinegar to remove and grease, then with white spirit. But it made me realise, people also just use adhesives to attach solar panels - and I wonder if the manufacturers use release agents when casting the brackets ? I chose to bolt mine down too, using Rivnuts, but it's a scary thought. Thanks again, you have saved me a lot of wasted effort.
Great tip Rick, one I avoided though as I sprayed my two vents black to colour code them with the colour of my van. I did noticed the residue on the surfaces when I was etching them ready to paint, so you are spot on there. I also used Isopropanol on a cloth to ensure everything was clean. Another tip is to pre-drill the mounting holes and clean all metal filings away (FantasticFan specific) and to not use self drilling screws, this is due to those metal filings also causing ways for water to create a leak, so best to take the extra time in cleaning everything, etching, and using alcohol based solvents to ensure a good strong bond.
Nice one Rick,its a good thing you made this video,bet its helped a lot of people out, I was thinking of all that time you spent doing the job :/you would have thought they would have mentioned that in the fitting instructions. Never mind at least you managed to put it right mate :)
Aaah, yes that makes sense. I was trying to figure out what on earth might have caused the problem. I think that would have had most people scratching their heads. I do wonder why they can't give these things a wipe down with Isoprop before they're assembled, but I guess that would add to the price, and there would still be a recommendation that you wash them thoroughly before fitting. On the plus side, at least you now have a spare fully functioning roof light!
Well said Rick; Damon just released a video stating the same problem after You'd told Him about the problem so that 'he' didn't make the same mistake with his Rebuild of Nina :-)
good advice. I think it wise to rough up any surface you are using adhesive on. A pre-wash with detergent and then a wipe with acetone or similar degreaser (to eliminate any film left over from the detergent) will ensure a vice like grip by the adhesive. i have noticed that professional window installers always run a low grit sandpaper over the paintwork prior to affixing the window. Just an extra bit of redundancy and security.
Ha ha good advice ! Exactly what I did when I refitted it to Nina, video to come ;). Thanks again mate, Nina is getting scarily modern looking with stuff like that being fitted ! :P
I absolutely love your channel. I love that you have been successful while keeping your subject matter fairly broad, and maintaining a monthly cadence. I was first drawn to your video about converting an ordinary point-and-shoot into a night vision camera, because of my interest in tinkering with things. As I said, you haven't restricted yourself to just that topic, which I think is brilliant. I have subscribed and look forward to watching. I don't currently have anything on Tinker Tube, but hope to soon. In the meantime I've been helping my son with his own channel, The Dabber Supreme (its a toy and game review channel). Take care.
A really good tip for sealing anything with any sort of silicone, is to clean the surface with a solvent. Most silicone is solvent based anyway. I generally use brake cleaner. Which is just solvent/degreaser in a can. I had the same sort of carry on sealing in a new shower base. The silicone would not "stick" to the base its self. After a quick spray with brake cleaner, all sorted. Just be careful using solvents on plastic though, as it could damage it and make the plastic brittle if not rinsed off.
a bit like putting new break disc on, give them a good clean, or you might not stop, :), good info, even i learned some think and I am a know it all , thank you
Thanks Rick ! Wish I had seen this earlier !! Just installed a Heki 2 and leaked like a sieve !! Did a second thick layer again of sikaflex and made no difference !! very frustrating.
Im sure its been mentioned but silicone mastic is not the best product to use for rooflights and windows especially on something that moves like a vehicle. A non drying bedding sealant is what should be used. I have always used Hodgson Seamseal and will be using it on my next build starting this month. Enjoying your videos 😎
Nightmare mine has just started leaking again always this time of year when you want to use your van and then you go look inside and find all the roof soaking wet. The weather don’t open at the moment either showers pouring down sun comes out rains again. So you try and find the time to do it. I’m gonna have to try again next weekend run out of time now thanks for your voice. I will use that knowledge of yours. Take it out and give it a good clean. Also, what’s the best silicone to use?
Just typical isn't it? Glad the video was useful, Cider. I nornally use Sikaflex - can't remember which specific one, but they're all pretty good. One of the many self-build camper groups on Facebook will probably give you the answer for the best one to use. 👍
If the manufacturer has not bothered washing off mould release agent when these sklights are so expensive is unforgivable. Mine (an MPK) is made of polypropylene (PP) - which is notoriously resistant to adhesion anyway. Tried your technique repeatedly and it has leaked repeatedly, unfortunately. Just bought a brand new one and I'm going to try cleaning, sanding and then spraying with PLASTIC PRIMER paint. I hope that the sealant/adhesive will then bond to the primer. Wish me luck!
mould release agent - thats what its called - Isopropanol wipe to remove it - should come with the kit if the manufacturer is too lazy to remove it themselves
Maybe you could use the spare rooflight on your shed :D Yep, i learned long ago to at least use sandpaper on any surface i'm going to use adhesives, whether it be mastic or other glues.
Couldn't find any information on this skylight when I fitted it two months ago. Here I am on the road with a sudden leak. Now your video shows up! Got to try and remove that sikaflex from the van roof now. Any tips?
How frustrating for you. Great tip though. I must have just been lucky with mine, or perhaps you were unlucky and got one that had not been washed. In any case, worth doing.
Oh my gosh today I just installed my first Skyline a job that I thought was going to take like an hour and be quite simple one it took about 4 hours and 2 feel like I run a marathon now so worried about the rest of my conversion
I really do think as part of the manufacturing and assembling proses the companies making theas should be washing of any mold release chemicals that are still on them and conditioning any attachment parts for use with construction adhesives.
Hello from Arizona. Anybody know if the mastics... Sikaflex 512 or is it 252 or the mentioned CT-1 Travis is available in the states or what the equivalent is? Getting ready to replace my large Midi Heki roof light in my motorhome and certainly want no leaking issues! Mine smashed in pieces when gale force winds threw it forward and broke. What a hassle it’s been finding a replacement because these are not sold in US any longer. Had to order from UK today. Who knew I couldn’t buy a replacement through Dometic US? They were zero help but Jacksons Leisure LTD came to the rescue.
