Fibre glass v Felt for flat roofs

[essexmick]

I've just bought a 1930s semi with a flat roofed extension.

The surveyor has identified extensive moss on the felt lining to the flat roof, and has said moss needs to be removed, which will take some of the roof with it, which means whole thing needs to be relined.

A builder recently came around and said the solution would be a fibre glass roof, he reckons they're more durable than the felt ones.

However, I've just had someone off mybuilder say that builders would say that fibre glass are better, because they're easier to do.

So I was wondering whether anyone had any views on what would we better for the roof: fibre glass or felt?

 

[freddiemercurystwin]

Have you actually looked for yourself at the moss? If the roof isn't leaking why does it need replacing? Photos please.

All flat roof materials are much of a muchness provided workmanship is good.

 

[essexmick]

Have you actually looked for yourself at the moss? If the roof isn't leaking why does it need replacing? Photos please.

All flat roof materials are much of a muchness provided workmanship is good.

Yes, I've seen there's quite a lot of moss on the roof.

Surveyor said that is there's moss on the roof, this damages the roof, and will mean leaks are likely.

I'll get you a photo.

 

[essexmick]

Have you actually looked for yourself at the moss? If the roof isn't leaking why does it need replacing? Photos please.

All flat roof materials are much of a muchness provided workmanship is good.

Here's the photo of the roof, what do you reckon? Does it need replacing?

I had a builder say to me today that moss on a felt roof is not necessarily a problem.

He added that a fibre glass roof is more expensive and better than a felt roof, because its likely to last longer, but he said both materials were good.

Untitled

• essexmick
• 14 Sep 2014
• 1

 

[dilly]

The good thing about grp is that nothing sticks to it,so the moss has nothing to anchor into and you can pressure wash the roof as well.

 

[essexmick]

The good thing about grp is that nothing sticks to it,so the moss has nothing to anchor into and you can pressure wash the roof as well.

What is grp?

 

[essexmick]

The surveyor who identified that the roof needed removing said that I should get an estimate for a modern kind of elastomeric felt?

I'm assuming this is not the same thing as fibre glass?

 

[freddiemercurystwin]

I've said my piece, which still stands, but can't see anything with that pic, too small.

 

[essexmick]

Another roofing company has just recommended a rubber surface, from Firestone.

Does anyone have any thoughts on this surface?

 

[geraldthehamster]

The surveyor has identified extensive moss on the felt lining to the flat roof, and has said moss needs to be removed, which will take some of the roof with it, which means whole thing needs to be relined.

I would get up there and see how attached the moss is. I bet you'll find you can just lift it off in handfuls without damaging the roof.

Surveyors commonly identify potential, rather than actual problems.

Cheers
Richard

 

[HERTS P&D]

I had moss on my flat roof, mentioned by the survey. It took 7 years before it leaked.

Save your pennies for a rainy day.

Andy

 

[essexmick]

I had moss on my flat roof, mentioned by the survey. It took 7 years before it leaked.

Save your pennies for a rainy day.

Andy

If you don't mind me asking, once it starts leaking, isn't that too late?

I mean presumably the support to your roof, and the plaster in the ceiling has to be replaced, at the point you find out the ceiling is leaking, because the water has to travel through all that for you to know a leak is occurring?

 

[essexmick]

One other thing is that we are going to get a new boiler, and the heating engineer has said he'll put a new flue through the flat roof, which will open the felt up.

Do you think that we may as well replace the roof anyway, once the flue has been put through, or is it an easy job to patch it up around the flue?

 

[essexmick]

I've just noted that the surveyor has pointed out that the flat roof structure has no external openings to ventilate the flat roof structure.

What does putting ventilation entail? And how much would it cost?

 

[geraldthehamster]

I've just noted that the surveyor has pointed out that the flat roof structure has no external openings to ventilate the flat roof structure.

What does putting ventilation entail? And how much would it cost?

I'd use the survey to light the stove, and worry about these things if they happen.

Cheers
Richard