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nss1888
11-12-2006, 10:46 AM
Hey folks...

My hoose has a flat roof on a section of it ( it was extended before I moved in)

In the cavity between external side and Plasterboard there should be some form of insulation but there isn't..

Now this leaves me with a bit of a problem. I want to put insulation in the cavity, but I Dont want to take off the external side and put insulation in OR take ALL the plaster board down and the replace it after putting int the insulation from benieth...

Can you get insulation pumped into this cavity (cavity wall insulation type stuff)??

And if so who/where/how much etc???

Any help greatfully appreciated...

sticky
12-12-2006, 12:14 AM
i think it would depend on if its a nine inch wall cause if it aint the pressure would just push all the plaster boards off and bow if its a nine inch with 3 inch cavity or 4 inch brick and block i dont think there will be a prob

nss1888
12-12-2006, 08:39 AM
Ta for the reply sticky,

but I want the insulation in the roof between the external facing felted side and the internal facing plasterboard side... not he walls (which are only one breeze block thick, i.e. no cavity to insulate)...

The size of the cavity in the cealing is probably 6-9inches...

I'm guessing from your comments that this wouldn't work as the pressure of injection would bow the plasterboard...

Is there any other way I can insutale my flat roof??

sticky
12-12-2006, 06:49 PM
i think the other way of doing it would be making a new ceiling so it would be like 4 to 6 inch lower but you would be able to insulate between platserboards if you know what i mean

nss1888
13-12-2006, 08:34 AM
Aye that might be a plan.. ta for your thoughts....

I had thought about the loose insulation stuff a leaf blower and only removing one of the plasterboard sections along one of the walls perpendicular to the joists... and then blowing the loose insulation stuff through the cavity... Probably wouldnae work, but it was a thought... :Hammer:

sticky
13-12-2006, 08:16 PM
easy to do m8 hope it works for ya wont take long to put it up cheers

garlad
01-03-2007, 03:25 PM
I am currently looking at putting insulation over my flat roof, and putting a new felt over this. Builder due out tomorrow. Will let you know results

Hitman
01-03-2007, 11:52 PM
Before you start trying to put insulation in a flat roof you must first find out what type of flat roof it is.
All flat roofs now are known as warm deck roofs.
This means that the roof decking in made of an insulation material like pearldeck or kingspan.

This type of roof does not need internal insulation as this is taken care of by the decking itself.
This type of roof is not vented either because the idea of ventilation is to stop condensation building up in the roof void caused by the hot air inside meeting the cold air outside.

A warm deck roof does not allow this to happen and so is completly sealed in.
The insulation properties of this roof are far superior to the old type and the sealed gap between the deck and plasterboard create even more insulation.

If your flat roof does not have ventilation vents i would guess its meant to be this way.

I was told by building control that if you cant put insulation in a warm deck roof, it will cause condensation in the roof void and give you a real headache...Dont quite understand why.

If you have an old type roof then it may be possible to take the facia board off and poke insulation between the joists with a lenth of timber or something.

Note: If it is an old type roof...(by old type i mean that the decking is just plywood or chipboard) and it does'nt have vents then it has been bodged.