522 Sealant

[Marty101010]

Hi, All.

I sealed around a skylight on a caravan with 522 sealant and have noticed a couple of little bits I have not sealed properly, can I go over it again with another layer? Thanks.

 

[Damian]

How did you do the first seal, did you remove the rooflight and clean all the old sealant off both rooflight and van?

If not then the job you did will not last very long as new sealant will not stick to old.

 

[Beachball]

on our caravan the skylight was checked by my caravan repairer he got it done for me some members on here would do it themselves they are very handy .

 

[Marty101010]

How did you do the first seal, did you remove the rooflight and clean all the old sealant off both rooflight and van?

If not then the job you did will not last very long as new sealant will not stick to old.

Hi.
I did not remove the skylight completly I removed all the sealant on the outer edge, the sealant that the sky light was set onto that I could not get to is still there. I cleaned the area with a 50/50 isopropanol and water mix.

 

[Damian]

Sadly you have only achieved a very temporary fix.
The only way to get a good watertight seal is to remove the skylight and clean it and the van roof and use new mastic on refitting.
Oversealing, which is what you have done is not very effective and may cause you more problems in the future.

 

[Damian]

Sadly you have only achieved a very temporary fix.
The only way to get a good watertight seal is to remove the skylight and clean it and the van roof and use new mastic on refitting.
Oversealing, which is what you have done is not very effective and may cause you more problems in the future.

 

[Marty101010]

[/QUOTE]

Sadly you have only achieved a very temporary fix.
The only way to get a good watertight seal is to remove the skylight and clean it and the van roof and use new mastic on refitting.
Oversealing, which is what you have done is not very effective and may cause you more problems in the future.

Oh dear. I was hoping that was not the case.

If I was to do that is the 522 sealant the best thing to use.

I did not have any leaks the mastic was looking a bit rough around the edges.

 

[Marty101010]

If I did take the roof light completely off it would probably be better putting a new one.

if I did get a new one will I still be able to use the inside trim on the caravan with the blind and fly screen, is it only the top bit you buy that sits in the hole.

 

[Damian]

There is no need to get a new unit if the current one is not damaged.

If you did decide on a new one, then they come complete inner and outer.

However, on the current one, the inside is held either by some screws around the edges or by spring clips, depending on the make.

The outer will take some careful removal using either a plastic scraper or fishing line works quite well in a sawing motion.

Removal of all the old mastic takes time, use a plastic scraper, not a metal one , and then clean the area with white spirit followed by Methylated Spirit.

Soudall Fixall is a good mastic to use and is cheaper than 522, and is easier to use and tool to a smooth finish.

Use a really good bead around the rooflight where it will sit on the roof so that when the inner is fitted to the outer and pulls it down, mastic comes out all around the edges, the tool off to form a smooth finish.

 

[Marty101010]

Thank you Damian.

 

[Marty101010]

There is a few different kinds of the soudal fix all, what one should I get.

 

[Damian]

I use Hi Tac White all the time.

 

[Marty101010]

Great, thanks.