Leaking Roof

[Samantha_374233123]

Dear All,

I have just bought a rather old, but nice Bailey Senator, it's about 10 years old.

I'm having trouble with a very leaky roof which has caused damp to seep through the back wall which will need replacing.

Can anyone recommend a waterproofing product we can use to cover the entire roof?

Should we use a membrane or a sealant paint?

Really grateful for any suggestions as we are having trouble finding anything that isn't a sticky black colour!

Thanks.

 

[Damian]

Samantha, have you proven that it is the roof causing the problem, or is it the rails above the windows, or awning rails which are letting water in?

It would be quite unusual for a roof to leak, apart from where there are any joins, but it is very often the external rails which the seal fails on, and lets water into the van, but this can be fixed by removing the rails and resealing them .

Until you determine exactly where the problem is, it is difficult to suggest a remedy.

Trying to cover the whole roof with anything is almost impossible, and a rather pointless waste of time and money.

 

[Samantha_374233123]

We think that the water is coming in through the centre join in the roof - as the ceiling inside the van is damp too. But as far as we know it could be leaking in any of the other spots you mentioned too. We'll investigate further. Thanks for the advice.

 

[Damian]

Samantha,

Now that you have said there is a centre join along the roof, it is definately a case of resealing the van.

You will have to remove any external rails or join covers, remove all the old sealer, which may be a bit more difficult on the roof, and after cleaning with white spirit, reseal using Silkaflex 221 or similar.

You will find rusted screws which will have to be removed, but it is better to throw all the old screws away, and replace with stainless steel screws as you refit the rails etc.

 

[Anthony3]

I agree with Damian's diagnosis.

You really need to get the 'van under cover to stop water getting in.

Failing that, go over the joins with roof sealing tape from a DIY merchant or Duck Tape etc, but you need to apply it to a dry surface.

When you come to do a proper repair be prepared to do some 'woodwork'.

The internal wooden battens may well be rotten, so you will be unable to screw anything firmly back in place. The wood may need replacing or, if not too bad, drying out and infiltrating with a resin wood hardner.

Stainless steel screws are a good idea and screw the screws into a 'new' position; don't use original screw holes if at all possible.

Sikaflex 221 or the newer one (252??) is very good stuff which I've always used, but be aware it is both an adhesive and a sealer. Once set it is VERY difficult to remove, so get everything positioned correctly.

Whatever you do, do not use silicone based domestic sealants as they have no adhesive properties and are useless where any flexing is involved.

Some so-called non-setting sealants used in the caravan industry actually harden and crack over the years thus letting in water through the cracks; personally I'd keep away from them although there may be better polymers available nowadays.

Last time I did it, I was lucky to have a dry spell of ~ 2weeks to work on the 'van, otherwise you'll need to find a friendly farmer's barn or get a cover over it.

Good Luck