Fiamma Roof Vent 28 leaking saga!

[fairwynds]

So, back in May I bought and fitted a Fiamma roof vent to my Hitop. Top section of fibreglass roof is flat and I made up a wooden framework inside the van to give the required minimum depth. I followed the instructions to the letter and even used a brand new tube of Tigerseal adhesive sealant. Anyhow, all was well for a while but with all this rain we've been having the roof has sprung a small leak.
This afternoon I removed the vent completely. The sealant came away from the vent itself without trace, but was firmly adhered to the roof and had to be cut off with a Stanley blade.
Couldn't say for definite how it was leaking but my van is always parked nose up on the sloping driveway which doesn't seem to have helped.
Anyhow, planning to reseat the vent, new sealant, but this time I will use four matchsticks to sit the vent on whilst allowing the sealant to slightly cure, then when I remove them and screw the thing down I'm hoping it won't squeeze out too much and result in a decent thickness of sealant.
All in all, a pain in the a***!

[DavidPallister]

might be worth roughing up the mating face of the vent as well so the sealant sticks to it?

[fairwynds]

Well, all sorted, for now anyhow. Will only know if all is well after the next batch of rain
Roughed up the mating surfaces and used Tigerseal. BUT this time I used plenty! (Think I was guilty of trying to do the job too 'neatly' last time!).
Put vent into hole 'dry', then used black electricians tape to mark all around, giving me a 2mm gap - this would allow me to run a finger around the excess sealant and then get a clean line when tape peeled away.
Sealant bead around the hole in roof, then a second fat bead of sealant around that, and also around the groove of the vent itself. Dropped the vent onto the roof, and used matchsticks to support it whilst sealant cured for a couple of hours (I put some sealant on a scrap of wood so I could keep an eye on the cure rate)
Later I removed the matchsticks and wiped away excess all around, and then a final tidy up with some white spirit on a rag.
After five or six hours I tightened the 8 x fixing screws from inside the van, equally, by another half turn. This squeezed out a further, very neat, bead of sealant which has been allowed to cure fully.
All done, let's wait and see

[max and caddy]

Any pics? I might get one of thes myself..oh and what roof?

[fairwynds]

Any pics? I might get one of thes myself..oh and what roof?

The vans a Bilbos conversion and the roof is their Astron.
Not a great photo but only one I've got on the computer at the moment. Lots of info on Fiammas site.
Main thing is the requirement to fit the unit to roof thickness between 2.5 and 5cm thick, so the standard thin fibreglass Hitop roof needs a frame fitting to accommodate the vent.

[SamsBus2012]

Had a 28cm MPK pop up vent which went brittle and disintegrated on the A38 last summer. Replaced it with a Fiamma 28 (including making up a frame to pack it out). I think its well the worth the slightly higher cost over a new MPK as, imho, its a much better design. Better vent when cooking and if you go for the white one you dont necessarily need additional blinds to block out light.
Fitted mine with Sikaflex 221 which stays slightly flexibe when cured. Dont know if that differs from Tigerseal.

[fairwynds]

Had a 28cm MPK pop up vent which went brittle and disintegrated on the A38 last summer. Replaced it with a Fiamma 28 (including making up a frame to pack it out). I think its well the worth the slightly higher cost over a new MPK as, imho, its a much better design. Better vent when cooking and if you go for the white one you dont necessarily need additional blinds to block out light.
Fitted mine with Sikaflex 221 which stays slightly flexibe when cured. Dont know if that differs from Tigerseal.

We can compare, over the next 12-24 months! The Sikkaflex is top stuff.