£1 per roll Loft Insulation

andrew-b

Some updated stats from this thread:

19 orders for a total of 440 rolls = average 23 rolls
11 orders with unconfirmed numbers of rolls = 253 based on above average
Estimated 693 rolls from 30 orders

The_Grim_Reaper

Skint_Catt wrote: »

How can you work out how much you need? We're in rented and there's sod all insulation in the roof - I'd rather pay to insulate it than waste money on heating going out through the roof!

The current recommendations are for a total of 270mm of insulation, so if you have no insulation at all at the moment you'll need to order both 100mm rolls and 170mm rolls:
Measure your loft area, you can do this on the ground floor. If it's a simple square or rectangle shape then it's: Length in metres x Width in metres = metres(squared)

then for the 170mm deep, divide the metres(squared) by 3.36 = rolls required, round up to nearest full number
then for the 100mm deep, divide the metres(squared) by 5.76 = rolls required, round up to nearest full number

e.g 6mtr x 10mtr = 60mtr²
60mtr² ÷ 3.36 = 18 then round up if necessary (rolls of 170mm)
60mtr² ÷ 5.76 = 10.42 then round up to 11 (rolls of 100mm)

order:
18 x 170mm Rockwool Insulation (nPower offer price £1/roll)
11 x 100mm Rockwool Insulation (nPower offer price £1/roll)

The nPower/Build Center calculator could be up and running again soon http://shop.build-center.co.uk/build/DIYcalculator/diy_loft_calc_new_v2.htm

andrew-b

Grim reaper..your maths is screwed mate!!!

6x10= 60 square metres

3.36 square metres in a 170mm thick roll
5.76 square metres in a 100mm thick roll

Need to know how much insulation already there ..if it's upto tops of ceiling joists then you have 100mm already and would need 170mm insulation. The area of 60 (for example) divided by 3.36 = 17.86. round up = 18 rolls of 170mm insulation

If no insulation at all then you need the 18 rolls of 170mm insulation PLUS the same area worth of 100mm. For 60 square metres that means you need 60 divided by 5.76 = 10.42..round up = 11 rolls of 100mm insulation PLUS 18 rolls of 170mm

60 square metres is big compared to most houses.

The_Grim_Reaper

andrew-b wrote: »

Grim reaper..your maths is screwed mate!!!

6x10= 60 square metres

3.36 square metres in a 170mm thick roll
5.76 square metres in a 100mm thick roll

Yeah I must have spent tooooooo long on the phone or something DOH! LOL

Thanks for sorting me out :T

twiglet98

Many thanks, wish I could have seen this earlier and will try the local Build Centre in the morning. We have 100mm already, ground floor area is about 7 metres by 9 metres so quite a big space. I qualified for a Warm Front grant to top it up but the fitters arrived and refused to go into the loft as we have asbestos ceilings, so we'll have to get masks and do it ourselves!

joecassels

I tried repeatedly to get through today by phone and web but had no luck. Does anyone know if the ship's now sailed?

The_Grim_Reaper

joecassels wrote: »

I tried repeatedly to get through today by phone and web but had no luck. Does anyone know if the ship's now sailed?

Not sure about that, seeing as the Build Center's websites down. http://shop.build-center.co.uk/build/indexa1.html (just getting redirected to npower at the moment) You could try the free 0800 529529 or your local depot in the morning when the mayhem will, I have no doubt resume. Well worth a try though I'd have thought. First come first served!

little_acorn_2

Skint - here's how to calculate for yourself.

First measure the length & width of your loft in metres. Then times the two measurements to give you the size in square metres. (For example, 2.5m x 7.7m = 19.25 sqm).

This bit taken from pdf on npower website:

If you've no insulation you'll need 100mm thick roll for between the joists and 170mm roll cross-laid over at a right angle.

Coverage of one roll of 100mm is 5.76 sq metres.
So divide your loft size in square metres by 5.76 to give number of rolls required. (In example above, divide 19.25 by 5.76 = 3.34 rolls so you'd need to buy four rolls)

Coverage of 170mm is 3.36 sq metres, so again divide your loft size in square metres by 3.36 to give number of rolls required. (In my example, divide 19.25 by 3.36 = 5.72 rolls so you'd need to buy six rolls).

Here's a link to the DIY insulation guide on npower website http://www.npower.com/web/diyloftinsulation/ssLINK/diy_insulation_guide

kevmcfad

***UPDATE***

The website's totally knackered now. I tried earlier but it would only let me get to the stage of estimating the floor area. When you click through to this link http://www.npower.com/web/diyloftinsulation/index.htm and then click on "Calculate Cost - Free Quote" it only refreshes the page and gives this message:

"Due to unprecedented demand for this offer, our partners at Build Centre are currently unable to process orders.

Please try again soon.":mad:

little_acorn_2

kevmcfad wrote: »

***UPDATE***

The website's totally knackered now. I tried earlier but it would only let me get to the stage of estimating the floor area. When you click through to this link http://www.npower.com/web/diyloftinsulation/index.htm and then click on "Calculate Cost - Free Quote" it only refreshes the page and gives this message:

"Due to unprecedented demand for this offer, our partners at Build Centre are currently unable to process orders.

Please try again soon.":mad:

This should be a message to the government that people will insulate if it's cheap enough. Also just a reminder to anyone on benefits that you can probably get it done for free through any one of the energy providers, even if you're renting, as long as you have permission of property owner.