Loft insulation

27col

You lot believe what you want. I know what I believe.

mech_2

I'm just going by figures given by the Energy Saving Trust. They say you can save £205 a year by insulating an uninsulated loft to 270mm of insulation, but you only save £60 a year when topping up loft insulation from 50mm to 270mm. So what's the saving from 100mm to 270mm? Let's be kind and say £46. Even if I do it all myself and my time is worthless, how much insulation does that buy?

But they assume a per-unit cost of just over 4p/kWh in a typical house with gas heating. Typical usage is about 20500 kWh/year, so they must be assuming a gas bill with roughly £820 of tier 2 units. I'm a low user. My gas bill at the rates I'm paying now consists of only £240 of tier 2 units in a year, so I stand to save proportionally less. On that basis I'd only save about £13.50 a year.

So I have to empty the loft of junk (which is up there because I have nowhere else to store it), take up the boarding, build up the floor joists by 6 inches, add insulation, re-board the loft, put the junk back. How many times £13 will that cost in time and materials?

Except the slope of my roof encroaches on the upstairs ceilings. There's a 2 foot strip around the parameter of my house upstairs that I can't insulate by more than 4 inches anyway, so I wouldn't even save £13 a year.

Fire_Fox

Many people would make more money by selling the junk in their lofts on eBay etc. than they would do by insulating the space created!

missile

mech wrote: »

I'm just going by figures given by the Energy Saving Trust.

Don't believe everything you read. IMHO, it would take many years to recover your time and money.
1.It is a lot of work to lift the flooring
2.Working with fibre insulation is messy and it is not too kind to your hands or health unless you wear the correct PPE

Much easier and possibly save more by:
1.Only fill the kettle with the volume of water you need.
2.Switch off TV and a.n.other appliances. A Sky box on stand-by 24/7 wastes a lot of electricity
3.You could use the time you would have wasted to earn more money, than you would save.

allan673

you can get space boards from b and q etc, or wickes do a similar one for laying over chipboard floors. they are very expensive though so its not really cost effective.
im in a similar position, half of my loft is boarded out.ive got 120mm of insulation down now.i was going to take up most of the chipboard floor and then put down another 150mm of insulation to give me 270mm total.
i wasnt going to raise the joists, just lay it on top of my insulation now???

wywywywy

I personally would think that getting cavity wall insulation done would be more beneficial than adding loft insulation onto the existing adequate loft insulation. If you have a cavity wall that is!

smartpicture

The thing is, I'm not just looking at it from the point of view of saving money. My house already has cavity wall insualtion and the 4" of loft insualtion I mentioned at the beginning, but it's still cold. I just want to be warm enough.

I had a new boiler and central heating installed only a few years ago. I also keep a spreadsheet graph of all my electricity / gas costs (yes, I now it's sad!) and the cavity wall insulation made no difference that I could see. I was really hoping that more loft insulation would be the answer - but without giving up my storage space!

However, what people have said on here is starting to concern me. I never considered the extra weight when I boarded out the loft originally. In one bedroom, I can clearly see the shape of the beams pressing into the ceiling. Is this normal, or something to worry about?

silvercar

I'm getting loft insulation next week. My son's bedroom has been at 15-17 C most mornings this week, so I'm waiting to see if there will be an improvement. Current insulation is loose chippings of something and has blown about a bit, roughly 2-4 inches. Getting 10 inches apparently. Done via the energy saving trust people and costing £215 for 84 sq mtrs.

Mikeyorks

silvercar wrote: »

Current insulation is loose chippings of something and has blown about a bit,

.... fortunately we only have an inch of that as a base. It's so disgusting that even the fieldmice that come in won't touch it. It's some sort of mica ... and just brushing it to one side to do some wiring ... makes your chest tight (must send the OH up there - she's getting a bit droopy in that area ) and a mask is essential. So I trust someone else is doing all the work

missile

smartpicture wrote: »

In one bedroom, I can clearly see the shape of the beams pressing into the ceiling. Is this normal, or something to worry about?

Perhaps you could explain this a bit better?

In normal house construction, the roof joists hold up the ceiling plasterboard. Perhaps what you are seeing is the ceiling bulging down between the joists?

Whatever the cause, this is not normal and I would be concerned.