Cold Flat Roof No Ventilation Problem

Postby rossbardon » Sat Mar 05, 2011 8:29 pm

I have recently brought a property which has a old conservatory / extension at the back with a flat roof. I want to put up a new plasterboard ceiling in this room to replace the cardboard tiles which are on the ceiling. Upon removing the tiles I have found:

* Paper layer with one side film (looks like old radiator paper)?
* Wool Insulation maybe 100mm thick
* No ventilation!

The gap between the end of the joists and the decking is 155mm (top of slope) to 105mm bottom end (bottom of slope).

I now need to decide what is best to do.

1) Do I add vents into the soffits for ventilation? But due to the limited joist size I would probably need to forfeit having any insulation.

2) Or do I carry on with no ventilation and stuff it with insulation? (As it was already).

The roof is NOT in bad order considering its age and lack of ventilation but I would like to do what I can to improve its life span and reduce potential problems for myself in the future.

Advice gratefully welcomed!
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DIY EPDM rubber roofing kits and solutions

Postby welsh brickie » Sat Mar 19, 2011 11:41 am

fix 75mm kingspan insulation boards tight in between the roofing joists.On the outside drill and fix soffit vents for ventilation and plasterboard the ceiling job done...
welsh brickie
Rank: Project Manager
Posts: 2171
Joined: Sat Apr 12, 2008 7:54 am

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