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Foam spray on UNDERSIDE of roof tiles

Postby adrian-wales » Thu Oct 09, 2008 7:55 am

I have had a Quote from a company that say they can spray foam in our attic on the underside of the tiles,

Basically this will secure the roof and stop the need for the roof to be replaced.

The spray foam is similar to the expanding foam.

It apparently sticks like strong glue and completely covers the inside of the roof tiles so you can no longer see the tiles to a depth of 55 mil.

My question is...

Can anyone advise me on wether this is a good way of fixing/securing the roof ?

Does it work?

Has anyone here ever had it done?

And if so is a £3,500 quote a good cheap quote? as he says that they can do it for cash for that price, otherwise it will be £4,250
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Postby bobplum » Fri Oct 10, 2008 4:45 pm

use the internet and find a roofing association or something similar and question them
or for a thousand pounds go out and buy loads of expanding foam cans,large industrial type and a gun and do it your self?
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Postby midgie » Wed Oct 15, 2008 9:26 am

I agree with the previous reply. Contact the National Federation of Roofing Contractors for advise.
4K is a lot of money - I would have thought that a roof could be stripped and retiled with new underlay and battens for less.
This foam has been known to promote rot in timber it comes into contact with and makes reuse of the tiles impossible therefore valueless. If the tiles need to be repaired or replaced later then the job is extreemly difficult.
There have been reports of companies cold-calling offering this solution to problems that do not exist - homeowners are very vulnerable to suggestions that their roof is in a bad way. Roofs by and large will last for 50 to 100 years - if it isn't broke then don't mess with it.
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Postby forswaps » Sat Oct 18, 2008 5:52 pm

I am a roofing contractor myself and I feel it is close to a con, costs double a roof strip and once on makes any repair nearly immposable. where does the water go that gets through the tiles etc onto the foam, onto the wall plate, wont take long to rot.
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Postby spruce goose » Mon Oct 20, 2008 9:32 am

I agree with forswaps and midgie. These people are cold callers trying to scare you into departing with large sums of money. Does the roof actually leak? Have tiles started to slip down in places (a sign nails are rusting and starting to fail)? Can you see daylight cracks when looking up at the roof from the inside? If you allow them to spray this rubbish on the inside of your roof you could well render the whole roof unfixable! If any of the outside part of the timber joist, wall plate or ridge plate is exposed to the elements (which could be the case with cracked or slipped tiles and rotten battens) this will cause timber to rot away from the outside. You won't be able to see these problems from the inside and the first thing you'll know about the rotten timber is when your roof starts to sag in places, which is where the joists have failed. Get 3 reputable roof tilers in and get a quote for a proper job which will include new roofing underlay (breathable) and new battens. They should be able to use the old tiles if they' re any good! Good luck
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Postby the specialist » Thu Jan 15, 2009 7:50 pm

I know this is late but everyone is spot on with their advice. These salesman who often know nothing about roof's other than they are on top of the house just want a sale.

They don't realise that it is not a permanent solution as tiles and slates still deteriorate over time - from the top. They eventually need replacing and when they do the roof strip will be much more difficult and therefore cost a lot more. If the roof needs replacing so be it. They also tell you that the foam provides good insulation. They don't tell you before it works as an insulant you have to heat the whole roof space first. Hardly sensible is it. Insulation is best on the ceiling.

Hope you didn't buy it!
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Postby TheDoctor5 » Wed Jan 28, 2009 10:15 am

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