Loft Insulation advice please.

[36TEAK36]

I am looking for some loft insulation advice please.

I live in a standard 1930's 3 bed semi with a pitched roof. For the past couple of years I have noticed that around the edges of the upstairs rooms we get what looks like a very faint black mould. It only appears in the winter months, so I assume it is something to do with damp.

I very rarely go up into my loft, so to be honest I have never really taken much notice of things, but I have checked that there is insulation under the loft floorboards, and there seems to be plenty. One think I did notice was, previous owners had pinned very thin sheets of board to the beams of the roof, and when I removed one of these board there was just the roof tiles and no insulation whatsover underneath. I know virtually nothing about insulation, but I would have thought that there would need to be some sort of insulation there. If the boards were not there, it would just be the roof tiles showing, and this seems a little odd to me.

Any advice would be most appreciated.

[chas2008]

some older houses were constructed this way with no roofing felt/membrane its quite normal ..Wickes do a helpfull leaflet

http://www.wickes.co.uk/pcat/32insulate

[tezestwing]

Hi The walls are most likely to be single brick (not cavity) and if the roof insulation goes tight into the eves this could prevent or restrict ventilation thus in the winter any air is loaded with damp that then is picked up at the corner by the room plaster and most likely lath and plaster ceiling
The only solution is to try to draw back any insulation to let it breath at that point this is a must do if it is cavity walls so that air flow into the cavity isn't restricted
You could do just one sideto start with and see if it improvesyouuld take damp reading before and after with suitable meter obtain from DIY store HTH Tez

[tezestwing]

Sorry about the grammar but for some reason if I try to correct it goes into some sort of spasm and joins tex up when you type HTH Tez

[36TEAK36]

Thank you both for your advice.I will try a draw back some of the insulation to see if that makes any difference.

[The Builder]

With the greatest respect to Tez...... there are a couple of things I'd like to disagree with. I would be very surprised if a 1930s semi was not cavity built. Worth checking because cavity wall insulation would go a long way to alleviating what is most likely a condensation problem.
Removing insulation would also likely make the condensation worse. Make sure plenty of insulation is packed well into the eaves. Usually you would have to mess about with eaves ventilation (roofspace cross ventilation). In your case you have the perfect method of roof ventilation. Take down ALL of the board that has been tacked under the rafters. This is the root of your problem. The boards are preventing the natural flow of air (and water vapour) from escaping between the tiles(or slates).
In a perfect world ............ fill the cavity (if there is one) ............ load the ceiling with insulation, making sure that this connects completely with the cavity over the wall/ceiling junction (the most vulnerable spot)................. take down the boards under the rafters and let the roofspace breathe..............

[tezestwing]

with respect TB as far as I am aware it has always been a no no to bridge the cavity http://www.handymanknowhow.co.uk/savingenergy/loft%20insulation.htm this is only one of many site to recommend this also I was only pointing TEAK into doing a part at a time as you so rightly point out that there could be many options I didn't want to confuse the issue and take one thing at a time as clearly a lack of felt + some form of boarding with what sort of insulation twixt the roof joist ? needs some form of investigation to the problem btw I live in a 1934 semi that has solid wall construction so around that era nothing was in stone so to speak HTH Tez

[tezestwing]

http://www.handymanknowhow.co.uk/savingenergy/loft%20insulation.htm try again not sure why this site unable to copy and paste HTH Tez

[tezestwing]

try again with this http://www.ultimatehandyman.co.uk/insulation/loft_insulation.htm HTH Tez

[The Builder]

Thanks Tez ............... sorry about that :o)
1934 house with a solid 9 inch brick construction eh?............I guess it just depends which part of the country you're in :o)

[d0gsb0dy]

Tezestwing. With regard to your text problem, try pressing the 'insert' key.

[Sprayseal]

If you are looking for insulation, spray foam insulation is great and it is eco friendly. You can read more about it here: http://sprayseal.co.uk/. Hope this helps!