decking on flat roof

gardan47 · Posted: Wed Mar 28, 2007 3:01 am Post Subject: decking on flat roof

hi i am trying to find out if i can fit some decking on to my flat roof to make a balcony from the bedroom the roof was rebuilt 4 years ago with new boards and felt and seems still in good condition
thanks Gar

daverik · Posted: Wed Mar 28, 2007 9:10 pm Post Subject:

NO, not without spending a small fortune.

^woody^ · Posted: Wed Mar 28, 2007 9:12 pm Post Subject:

Yes you can.

You need some propriatary spacers under the decking.

Do a google for ' promenade tiles ' and suppliers of the spacers should be listed

freddymercurystwin · Posted: Thu Mar 29, 2007 10:11 pm Post Subject:

You need something like these; http://www.wallbarn.com/rubber-paving.htm

Are you going down the legal route? ie building regs, planning etc? No doubt you'll not want to hear this but your flat roof would have been designed as a flat roof whereas the potential loads on a balcony can be considerably more unless its only going to be tiny, still, thats a matter for your conscience!

kevnurse · Posted: Sat Mar 31, 2007 10:16 am Post Subject:

The supporting structure for your decking can only be the walls supporting your roof. You cannot use any part of the roof to support the decking (unless you have a supporting wall under it). So, this means that you have to fit beams on top of the walls and then span the roof area between the beams with joists. The length of span will determine the thickness of the joists. This, in turn will determine the weight of the joists and the overall pressure that will pass down through the walls into the foundations. If its an old building, the additional weight of your deck might not be significant, because yars ago they made thick walls and big foundations, but new houses are built for purpose on an economy basis and they are not designed to take additional weight. Get an architect and structural engineer to give you some advice. It might cost you a few hundred quid, but its worth it.