Roof insulation, anyone done DIY? Also some basic questions...

[thetigerwhocametoteax]

Yes I know not the most exciting of topics but I need to get some roof insulation sorted. Especially now its getting chilly and the bloody oil tank needs filling again.

We have an two old cottages that have been knocked into one, but still has two seperate attics. One is unconverted and just basic floor boards on floor and roof rafters exposed, no insulation at all. The other has been very basic converted and has some rock wool under the plaster boards but still freeeezing up there.

So really what I want to know if whether the rolls of insulation stuff you roll out on the floor or the insulation boards (like Kingspan) pushed into the spaces between the rafters is most effective / easier to do DIY / cheaper? Anyone done it DIY and have any tips? Good places to get insulation cheap? We seemed to have missed the free loft insulation deals, they are all now means tested and we are sadly not eligible....

Thanks!

The rolls, like Knauf I think it is, are definitely cheaper and easier. You just literally roll them out about a foot away from the eaves to allow some ventilation (instructions on the roll!). You can add more for a thicker insulation if you want which should be more effective. But you do put them across the joists so it makes walking in the attic tricky because you can't see the joists and could go through the ceiling if you are an idiot and not being careful

If you want to walk up there or store stuff then you need the insulated boards like the Kingspan ones. A cheapo own brand version were on offer I noticed a few weeks ago at my local BnQ, might still be. Also in my old house I put polystyrene type stuff between the roof trusses so that it was insulated under the tiles and on the floor, so that I could use the space.

Oh just noticed your ref to an oil tank. Wasn't there something on the news about them a few days ago? Maybe free replacement or summit under Green Deal? (not means tested)

you can theoretically get green deal cashback on oil boiler replacement and insulation. Good luck getting through the hoops, after which you MAY get cashback.

green deal? Green wash.

www.building.co.uk/government-to-tweak-failing-green-deal-cashback-scheme/5061000.article

Kingspan etc should do the trick and is what is planned for this house.

The DIY route for roof insulation is dead easy and effective as demonstrated by the fact that my cack handed DH has done it on our last 3 houses.

Rolling the woolly insulation out is veryvsimple but minimum thickness is now meant to be 270mm which will make it impossible to walj on and will mean you have a "cold roof" (ie. the heat is kept out of yhe attic space). If you want to have a space ypu can walk pn you will need to put rigid insulation under the boards and if you want a "warm roof" (ie one where the heat enters the attic but doesn't leach out through the roof) you will need to put indulation between the rafters in ceiling. It's all eady to fo (yhe rigid stuff cuts very easily) but pulling up boatfs/down ceilings is obviously a pain and disruptive.

Thanks for the replies. I think the "cold roof" / "warm roof" issue is the one I am unsure about. I guess it is better for things that are stored in the attic space to have some heat ie insulate between the rafters. However I guess for heat retention in the house the roll out stuff on the floor is better.

Does it make any difference as far as air circulation / damp issues which one you do, considering its a really old cottage? We've a grey slate roof which does get the wind and some rain coming through it at times!

Well, heat rises so it's best to trap that heat as low as possible, imo. From the sound of it, you're not short of ventilation up there but, to be honest, I'd be more worried about the leaky roof than the insulation...

agree with lalalonglegs, get the roof fixed properly - you shouldn't be getting water in no matter what. you certainly don't want water trapped in insulation making it damp

it is easy to do insulation, we done our roof. it just rolls out - once you get above the height of the rafters its easier to roll out as you can use whole rolls of it rather than break it up into pieces. its a really mess job though. once above the height of the rafters we used boards to walk on rather than guess where the rafters were then removed them when we finished an area.