2 layers on a flat roof?

[guinch]

I have an old flat felt roof on an extension to the house that had developed a leak over the winter. I patched it with tape to see it though but figure it needs replaced before another winter. Never having attempted a roof before I thought the first step would be to get some quotes see what the "pros" would do with it.

I have had one back there the guy will do the following:

• 
  Strip the roof..
  Recover roof with 1 layer fibreglass felt
  1 layer 4mm polyester torch on green mineral felt
  finish with flashings and raggle cut into wall.

Everything I read about felt roofs has three layers. Is the above two layer system legit or am I best to avoid this?

 

[^woody^]

That's correct for a Torch-on system.

 

[joe-90]

How much is he asking for?

 

[guinch]

OK if it looks OK then I might consider this as he is asking for £500 which is probably pretty reasonable. (its approx 10-12M sqr BTW).

 

[joe-90]

It's more than reasonable, it's cheap. Make sure the roof boards are good though.

 

[donemybit]

£500 for approx 11sm works out at £45.45 per sm. On that spec I would have thought thats about right. Its a days work, materials won't cost all that much.

 

[alan333]

If the roof boarding is planks I'd go for three layers, the first being nailed. If it's sheets like plywood then 2 layers would be ok, but I'd taoe tye joints first.