Fibreglass flat roofing repairs

  TopCat® 15:23 11 Apr 2009

Now for something completely different and I hope someone can help.

The extensions to my bungalow have about 67 sq mtrs of flat-roofed area covered with fibreglass. This is now showing its age as I can see the matting fibres in some places, just below the remaining surface coat.

Can anyone please suggest a suitable all-covering waterproofing treatment that is recommended for such a roof. I'm looking for a long-term solution that my son-in-law and I can apply this summer.

Thanks for your help on this query. TC.

  caccy 15:32 11 Apr 2009

We have the same type of roof, the top coat is just coloured fibreglass gel.

  TopCat® 15:38 11 Apr 2009

It's that top coat that is now very very thin and I'm looking for the right 'paint' to do over the whole area. TC.

  Fruit Bat /\0/\ 16:10 11 Apr 2009
  wiz-king 16:43 11 Apr 2009

I would think almost any two part polyester resin would do, but have a word with click here the preparation will be the hard work, it will need a good scrub down, rinse and dry with a couple of days dry weather.

  Woolwell 16:44 11 Apr 2009

How old is the roof? I suspect that many of these roofs do not have a life linger than 30 years.

  rdave13 17:38 11 Apr 2009

As Fruit Bat /\0/\'s link. It's a slightly cheaper version of Gell coat. Coloured resin and the catalyst comes with the tin. Roughen the surface with some glass paper (I find that belt sander belts are the best type)by hand and chemically clean the surface with acetone. Once the surface is prepared then use a cheap paint roller and apply it as thick as you can, making sure air is removed as much as possible while coating.
It's a dirty job but leaves a good protective coating on the roof. I chuck the tools after use.

  TopCat® 17:52 11 Apr 2009

Thanks very much for the link - and the firm is actually in Redruth, Cornwall which is a great bonus.


Checking the plans for this particular extension I see they were drawn up in 1979 but the actual job was completed in late 1980. Now you've got me worried as 30 years is up this year!

I'll have a chat with the company at Redruth and get their advice on how to proceed. Thank you everyone for the help. TC.

  2bathred 01:27 12 Apr 2009

ever thought of butyl rubber as used for fish pond liners. can be cut to any size has no seams and is UV protected. usually has a 30+ year g'tee

  JYPX 21:44 12 Apr 2009

TopCat® - I appreciate that you are perhaps looking for an inexpensive solution, but frankly your post is a pretty good endorsement for fibreglass roofs. Why not contact a specialist company and have it re-done? 30 years is not bad for a flat roof. I had my garage and my extension done a couple of years ago (to replace the horrible tar roofs) and consider it money well spent. The best aspect was - to my amazement and delight - the creation of a slight pitch on both roofs. Hey presto- no more flat roofs......

  Strawballs 22:03 12 Apr 2009

You will need to find out if it is a Polyester or Vynalester resin used in the first place, if the former then you can use either type or if the latter then it must be a Vynalester used to resin seal the roof.

If you are going to do the job you must abraid the surface then you can use paint rollers to apply the resin and it would not hurt to give it another layer of chopped strand matt, putt a layer of resin on the roof lay the matt on top while still wet then roll with the rollers to bring the resin through using a small amount of resin on the roller.

As said before it MUST be done in dry conditions untill completely cured and the warmer the better.

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