SIKAFLEX ALTERNATIVE?

Mtbcol

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Evening all.
It appears the sealant has failed on our roof vent and leaked water on to our bed.

It was sealed only a couple of years ago with Sikaflex 522 (?) or the one it superceded.

I've heard many people say it's not as good as its made out to be, so what could anyone recommend please? Some thing that could be applied and sets in water would be useful as it keeps @#_&! raining here!🤣

Thank you.

Colin.🙂👍
 
Evening all.
It appears the sealant has failed on our roof vent and leaked water on to our bed.

It was sealed only a couple of years ago with Sikaflex 522 (?) or the one it superceded.

I've heard many people say it's not as good as its made out to be, so what could anyone recommend please? Some thing that could be applied and sets in water would be useful as it keeps @#_&! raining here!🤣

Thank you.

Colin.🙂👍
I used white sikaflex ETB from screwfix for several sealing jobs on my MH roof over the last few years and it still seems to be adhering well.
I too also repaired our roof vent over the bed that leaked during the heavy rains we had a few months back, the roof isn't flat (PVC) so some of the fixing screws distort the frame where it's not supported, over the years the frame has cracked in some these places. Didn't fancy a complete removal so I enlarged the width of the cracks with a multitool so that I could get some sealant in. Has been fine up to now.
 
Stixall can apparently be applied when it's wet.

You can apply it, but it won't feckin stick 🤣 Otherwise I think the white is quite good, but not the clear oddly.
 
CT1 is supposed to be able to be used whilst wet, and is quite good stuff
CT1 does have excellent sealing qualities. However it is also a very powerful adhesive, and is effective for application whilst underwater. I have used it successfully for sealing to the underwater part of a boat hull. A potential disadvantage is that it can be very difficult to remove if the need ever arises, e.g. other skylight maintenance, etc..
Sikaflex 291 is also an excellent sealant with good adhesive properties and remains flexible (i.e. vibration resistant).
As with most of these products, it's sensible to allow them to cure for about 24 hours before tightening everything up, otherwise you simply squeeze most of the sealant out from the space you're trying to seal. So start with "finger tight" only.
 
Butyl tape is supposedly the best thing but it can make an awful mess, think it’s called butyl tape anyway, the black stuff that sticks like sh1te to a blanket.
 
Hodgson HS30 is very sticky and flexible
 
Just to say thanks everyone for the replies and suggestions.

I've not had a proper chance to look yet, and suspect it is the seal, however the water seemed to be coming from the inside of the unit? and when I unclipped the fly screen for an initial inspection the dished area around it was full of water, but there was no signs of staining or dampness on the ceiling or the wooded internal frame. I'm wondering now if the clear gen cover us cracked? It'll have to wait til Friday now, and daylight😐

Thanks again everyone 🙂👍
 
Whichever sealant you use a really really really good clean with cellulose thinners makes a world of difference
 
Another vote for butyl tape. Comes in white and grey as well as black. Used sikaflex and another DHL??? in the past and had to redo. Main thing is use a non setting sealant., clean surfaces work tidy. It can get messy, get the right width/thickness tape for your lights and leave paper on the one side until absolutely ready to marry surfaces. Strike any squeeze out to a bevel, there shouldn't be much if you use the right size.
 
Sikalastomer 710 butyl sealant was the recommended sealant for installation of replacement roof lights recently. I gave them a good amount all the way round the ran a bead of Sika white EBT around the outer edges after nipping the frames down and removing the excess 710.

Cheers

H
 
Butyl tape is supposedly the best thing but it can make an awful mess, think it’s called butyl tape anyway, the black stuff that sticks like sh1te to a blanket.
It is as you describe. But the surface you apply it to must have no flex as it has to compress to make effective - so no use unless you are typically squeezing/sandwiching from both sides, or pulling the surface up against the tape with a bunch of screws around the frame you are fitting.
(not sure if I am describing that well?)
 
If you want a proper manufacturers seal, you need to remove the frame and clean it up. I have found that many motor homes use the butyl seal on roof vents and side window frames. It works well providing you buy the right width, too wide and it makes the job harder plus it's a waste of money. You can't buy twice the width in the hopes of cutting it down to get the length you need as it sticks to everything that touches it, including the knife or scissors and whatever you are cutting it on. Otherwise Sikkaflex EBT + is very good but it does stick extremely well so get it right first time and wipe away excess before it sets.
 
It is as you describe. But the surface you apply it to must have no flex as it has to compress to make effective - so no use unless you are typically squeezing/sandwiching from both sides, or pulling the surface up against the tape with a bunch of screws around the frame you are fitting.
(not sure if I am describing that well?)
Don’t all roof lights work that way? All the ones I have had use an inner and outer that screw together to sandwich the roof between them, then a cover on the inside

Edit: just to add, I don’t use butyl, just saying that the stuff supposedly best, it’s what manufacturers use. I am too messy to attempt that so use Sikaflex or the sealant adhesive O’Leary sell but can’t recall name of that.
 
Don’t all roof lights work that way? All the ones I have had use an inner and outer that screw together to sandwich the roof between them, then a cover on the inside
pretty much I think. But if someone is doing a repair as opposed to an installation, they may apply some sealant product and then just press down for pressure rather than disassembling the entire window/vent for a 'full' repair. And while that might be ok for a tube sealant that you squeeze in, butyl tape would not work if you just lifted and then pushed down (IMO anyway).
 
pretty much I think. But if someone is doing a repair as opposed to an installation, they may apply some sealant product and then just press down for pressure rather than disassembling the entire window/vent for a 'full' repair. And while that might be ok for a tube sealant that you squeeze in, butyl tape would not work if you just lifted and then pushed down (IMO anyway).
I agree with that, if it’s leaking you would need to remove completely, thoroughly clean then re fix. Should really do that if using sealant though as well
 
Don’t all roof lights work that way? All the ones I have had use an inner and outer that screw together to sandwich the roof between them, then a cover on the inside

Edit: just to add, I don’t use butyl, just saying that the stuff supposedly best, it’s what manufacturers use. I am too messy to attempt that so use Sikaflex or the sealant adhesive O’Leary sell but can’t recall name of that.
I used the butyl tape method when I installed my Maxx Air Fan on my camper as that was the recommended way. It never leaked, so obviously worked, but I don't know how much better or different using a sikaflex type tube adhesive would be? Probably not a great deal?

Something that should be taken into consideration when choosing a repair product is how it will interact with any sealant already present. Some products just will not stick to other products and so you don't get an effective seal and you only need the tiniest gap for a water leak. (not on a motorhome, but I had a hairline crack in some rendering and every time it rained hard I used to get a virtual waterfall by the French Windows INSIDE the house about 8 foot away from the crack. Took ages to find that and a tiny application of a sealant fixed it.)
 
Just to say thanks everyone for the replies and suggestions.

I've not had a proper chance to look yet, and suspect it is the seal, however the water seemed to be coming from the inside of the unit? and when I unclipped the fly screen for an initial inspection the dished area around it was full of water, but there was no signs of staining or dampness on the ceiling or the wooded internal frame. I'm wondering now if the clear gen cover us cracked? It'll have to wait til Friday now, and daylight😐

Thanks again everyone 🙂👍
We had an ingress of water during a really heavy downpour and wind. The water was blown through the small slit vents in the plastic domed cover. Unscrewed it all and gave a good clean. Have had the vent open during a storm before, but nothing came through. Just put it down to wind in the right (or wrong!) direction.
 

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