leaking roof

[rangie]

recently bought a herald motorvan its a 1994 some minor holes have apearedin outer shell how can i repair them any advice wellcome

[fred22]

I am sure that if what I am about to say is incorrect someone will correct me but, as I understand it ,these holes are often caused by the aluminium roof covering oxidising into a white powder. At least that is what happened to me.

If the holes are caused by oxidisation you may find that the little hole you can see is only the tip of the iceberg and the metal will be paper thin for some distance either side of the hole.

I successfully treated mine in the following manner,

Clear around the hole until you get to good aluminium.

Tap the centre of the hole to make a small indentation.

Roughen/clean the surface of the indentation (emery cloth, course wire wool etc)

Fill the hole with a good quality car body filler just proud of the roof surface.. You can get some which claim to be for aluminium but I don't know if they are any different.

Smooth down when dry and paint to match existing roof

In an emergency Gaffer Tape or body sealer can be used to keep out the water.

 

[rangie]

thanks for the reply but i failed to metion its a moulded plastic shell

[rapidoman]

had same problem with autotrail few year ago :'( it sounds like the gel coat has blistered if so you should be able to remove damaged area and fill with epoxy resin or isopon and repaint. we had so many blisters that we took van to body shop and had whole roof repaired and resprayed. still going strong as far as i know ( changed van several years ago ) (lol)

[rangie]

thanks rapidoman you confirmed my thoughts cheers

[Derek Uzzell]

Rangie

 

If the holes in your Herald’s GRP roof are actually allowing water to pass through the roof (as seems to be the case from the title of this thread), then the problem may well be more serious than just damage to the gel-coat’s upper surface.

 

I used to own a 1996 Herald and recall that there were minor surface imperfections in its roof’s finish, which were probably inevitable given the large size of the moulding. I also remember that the GRP moulding was pretty thin in places, particularly in the overcab area.

 

If the holes in your roof go right through the moulded shell, or there is damage to the GRP layers below the holes (possibly due to rainwater finding its way through the outer holes into the inner glass-fibre layers and then freezing), simply repairing the external holes may not be sufficient.

 

I’m pretty sure Herald roofs used coloured resin in the gel-coat, rather than being painted, but, if you want to match the existing colour, then you will probably have to paint-spray over the repair as happened with rapidoman’s Auto-Trail.

 

Carrying out repairs to GRP is, in principle, relatively straightforward, but you might want to take professional advice before going down the DIY route. If you GOOGLE-search on “grp repairs” you will find plenty of useful information. There’s also a “Working with Plastics” chapter in John Wickersham’s “Build Your Own Motorcaravan” book that might be helpful.