Flat roof refelting questions

I have a typical 1960’s 3 bed semi that has a flat concrete roofed garage to the side that has been converted into an office. With heavy rain I am getting some damp patches lately on the office ceiling. I can see the felt on the flat roof is cracked and blistered in places, it has been there since the garage was converted about 25 years ago.

I got a roofer who was highly recommended by two different people to look at it. He is suggesting leaving the existing torch on felt in place and refelting on top of it with one layer of torch on felt. He says the existing felt will be a good base and eliminates the need for two new layers. I was surprised at his suggestions but I have no expertise in this area, maybe he is right.

Should the original 25 year old felt be removed ?
If it is ok to leave the existing felt, is 1 new layer sufficient ?
Any other comments or pointers welcome.

Tks.

No clue, but a proper roof is better. Why not ask a second roofer for an opinion.

After 25 years I would remove the old felt and insulate on top of concrete followed by 2 layers of felt.I had this done on a commercial roof a few years ago and it worked out perfect.

Thanks for the replies, it was a cold room so a few years ago I had it insulated internally including the roof so I’m happy insulation wise.

I assumed the way to go would be to remove the old felt and replace with 2 new layers of torch on felt. The roofer is saying existing felt is good as a base and 1 layer of torch on felt would be the norm in this case.

Has anyone else had similar or different advice ?

I will get another roofer opinion.

I have a similar set up and may need attention in the near future. Would you mind me asking what would be the approx cost .

I would advise the old layer be removed. I had an experience some years ago where the original layer was left and a new layer placed on the old layer. The old layer retained pockets of water and damp and when the last big freeze came, the water froze, expanded and destroyed the old and new layers leading to massive leaks when the ice thawed.

Make sure you put in battens, to make water run off.
I had a flat roof done years back, with no problems... he gave a 20 year guarantee.
The company is based in Rathmines area. I can look it up for you.

Billo said:

I have a similar set up and may need attention in the near future. Would you mind me asking what would be the approx cost .

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Don't know yet, quote will be emailed, will let you know when I get it.

https://www.grpfibreglass.net/?gcli...edQIm9boX_cBNBLDMw0bBKOPsJBoHBoC57YQAvD_BwE#/

Get a quote from these guys, great solution for flat roofs. I bought their kit and completed 3sqm concrete garage roof myself for about 300 euro. Two years in and as good as the day it was completed.
I would not keep the old felt for reasons stated above, and wouldn't use a roofer who recommends it.

I have no affiliation to this business.

Jumpingjacks said:

https://www.grpfibreglass.net/?gcli...edQIm9boX_cBNBLDMw0bBKOPsJBoHBoC57YQAvD_BwE#/

Get a quote from these guys, great solution for flat roofs.

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Thanks, I would consider a fibreglass roof but that website would not instil confidence.
It has many typos, looks like it was translated by google. Contact details are vague addresses in Dublin and Cork and only a mobile phone number.

Des Pondent said:

Thanks, I would consider a fibreglass roof but that website would not instil confidence.

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Agreed, and .net websites are easy and cheap to put out. Standard consumer advice would be to avoid companies who do not include correct contact details including a physical address on their website

That said, there has been a company of that name in existence since 2017, but that does not guarantee the website is genuine.