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I have a flat roof to do, its very old and the felt is brittle. It's got the loose gravel on the top and about 2 inches of moss all over it. I have cleared the moss but rain water still seems to pool in certain areas, very small pools and only a couple, is this normal. Also before I apply a new felt which has to be blow torched on the underside to stick to the existing old felt, how dry does the surface have to be, I've been told that if its damp and the excess water is swept off there shouldn't be a problem, also apparently there are other products out there which can be used specifically in damp weather. Any advice would be appreciated. Thanks, Roo
 

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Pompass Ass
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I have a flat roof to do, its very old and the felt is brittle. It's got the loose gravel on the top and about 2 inches of moss all over it. I have cleared the moss but rain water still seems to pool in certain areas, very small pools and only a couple, is this normal. Also before I apply a new felt which has to be blow torched on the underside to stick to the existing old felt, how dry does the surface have to be, I've been told that if its damp and the excess water is swept off there shouldn't be a problem, also apparently there are other products out there which can be used specifically in damp weather. Any advice would be appreciated. Thanks, Roo
You need to hire a roofer that knows what he is doing.

a BUG roof will hold water, that is normal.

The old roof including the old felt needs to be removed, then new felt put down, you can not have any moisture on the roof at all while installing a new roof system.

It will be cheaper and easier to hire a licenesed roofer and have it done right the 1st time.
 

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Call a licensed roofing contractor who is skilled with a torch. You're goign to burn something down.

The felt is not applied with a torch.

Puddles are normal and acceptable if they evaporate within 48 hours of the last precipitation event. check with the manufacturer of the materials for more information.
 

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I have done a few flat roofs. It is simple.
step 1. call roofing company
step 2. have them remove all the old junk & install EPDM (about twice the price of a built up roof)
step 3. enjoy not having to call your roofer again for 50 yrs.
 

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Roofer
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I have a flat roof to do, its very old and the felt is brittle. It's got the loose gravel on the top and about 2 inches of moss all over it. I have cleared the moss but rain water still seems to pool in certain areas, very small pools and only a couple, is this normal. Also before I apply a new felt which has to be blow torched on the underside to stick to the existing old felt, how dry does the surface have to be, I've been told that if its damp and the excess water is swept off there shouldn't be a problem, also apparently there are other products out there which can be used specifically in damp weather. Any advice would be appreciated. Thanks, Roo

You need to remove 100% of moss and "any loose" gravel.

Water will pool on flat roofs, so long as it don't pool longer than 48 hours it's pretty normal, over 72 hours is really bad.

The surface of the existing roof needs to be 100% dry.
If it's damp/wet when you are trying to get started you can use a broom to push the bulk off than use a cotton "string" mop to suck up the remaining puddles and than run your torch across the surface in quick motions to dry up the rest.

Run the torch 30 seconds to long in anyone spot and you overheat the new product which will turn into blisters in the near future, 30 seconds not long enough and you won't get full adhesion.
Either will result in premature failure.

If you can't afford to hire a roofing contractor than hire a roofer,
you supply materials and labor and let him/her supply experience.
 

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The felt is not applied with a torch.
:surrender: omg.. i dont even know you but i know exactly what your facial expression was when you wrote that.. lol... i cant stop laughing.

Aside from the extremely wise advice given already... you have more than blisters and ruined mats to fear. Run that torch to hot or too long and youll start a smoldering fire underneath the membrane... you wont even know its burning for about 3 days and it caves in and destroys everything it fell on.

Its a lot more complicated than you are aware of and i promise on everything I own, have, know, am worth.... that if youre looking to save money by doing it yourself, its going to cost you at least double.
 

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:surrender: omg.. i dont even know you but i know exactly what your facial expression was when you wrote that.. lol... i cant stop laughing.

Aside from the extremely wise advice given already... you have more than blisters and ruined mats to fear. Run that torch to hot or too long and youll start a smoldering fire underneath the membrane... you wont even know its burning for about 3 days and it caves in and destroys everything it fell on.

Its a lot more complicated than you are aware of and i promise on everything I own, have, know, am worth.... that if youre looking to save money by doing it yourself, its going to cost you at least double.
It was REEEEALLY funny 4 years ago when he posted it..
 
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