Loft insulation - how much did it reduce your heating bills?

[malcolm]

Has anyone put a bit more insulation in your loft? Older houses tended to have 100mm of fibreglass between the rafters and the current recommendation is about 300mm.

I'm trying to build a calculator for myself and want to make it a bit more accurate than the official calculations that you have to pay for which don't seem to take into account rising heat - they say I would be better off insulating the ground floor than messing with the loft.

For me the loft insulation seems to have made way more difference than that predicted in the official calculations. I don't think the heating upstairs has come on at all since it was installed. Bills for me are difficult to judge as it has been warm and the insulation only went in a month ago. It is annoying as I need to insulate other stuff and won't get to see what difference it makes by itself.

Anyone else added a bit more into the loft? What did it do to your heating bills?

 

[brightspark]

before i insulated the loft our roof never had snow on it and u could feel the cold of the celing in the rooms i stuffed the attic with insulation and boarded over most of it . the rooms are a lot hotter and my roof is one of the last ones that the snow thaws out on -

 

[JEZGUZ]

My flat (top half of a semi) used to lose heat very quickly. Had a visit from the energy efficiency people and the landlord, the energy bloke had a look in the loft and said there was no insulation and the landlord swore blind that it had been done, I had a look and apart from bird and wasps nests there was sod all up there. Landlord seemed to be not bothered so I found a place doing insulation cheap and spent £27 on some basic quality stuff. Bills have dropped by 50% (£99.00 for the last quarter, gas and electric combined) might put some more up there as I've still got some left over.

 

[DecK]

they say I would be better off insulating the ground floor than messing with the loft.

Who said that? Whoever it was deserves to get battered around the head with something hard. Under floor insulation on a ground floor isn't going to do much unless you have underfloor heating installed. In this situation it serves as a barrier to the heated floor slab having heat drained away through conduction with floor build up.

Main sources of heat loss are roof and walls. 300mm of MGW in the attic is the standard and the next best place to concentrate is to pump the cavity in the external wall if there is one. Heating loss through the floor is on par with losses through doors and windows in a normal house

 

[malcolm]

JEZGUZ - In a top floor flat stuff it up to 300mm thickness in thw loft. Make sure there aren't any air gaps. I reckon the flat downstairs would pay for your heating.

 

[Pete.]

When I bought my house it had no insulation at all. We had 200mm of insulation put in the loft under one of those govt schemes and it transformed the place. I don't know how much I've saved on the heating but I did have to buy a fridge

 

[rtbcomp]

If you have a cold water tank in the loft insulate on top and round the sides, not underneath, to keep it from freezing.

 

[JEZGUZ]

I can tell when the downstairs people are in, I don't have to put my heating on as the heat from their flat rises through the floor

 

[waldershelf]

My loft has between 12 and 18 inches of insulation and it hasn't reduced my bills at all.... its just a case of doing what you can to keep them the same.

 

[snowcat]

I put masses into mine when I did the loft conversation, My original house had barley 50mm. I went nearly 600mm in the side lofts of fibre, then 100mm of sellotex board in all the studs, top loft was also fibered to about the same then again boarded, walls were solid 9" typical 1950s which I skinned with 75mm fibre board then put shielded plasterboard on the top.

I have never once regretted going OTT on the insulation, It is such a tiny cost factored for 10-20 years over heating costs.

Iv just started on my new house a 3000 square foot 1800s brick stable block, I plan to rescreed all the floors and incorporate 50mm of insulation and UFH on the slab, then false cavity all the existing walls, I have yet to decide on max roof insulation because I want to have some beams exposed, however as I'm heating from biomass or GSHP on 40C water temps I want as much efficacy as possible.

 

[BrokenBiker]

when i was in a flat, i was top floor and the loft was rammed with insulation, we never had to put heating on at all as when it got cold the old guy downstairs put his on and we were boiling

 

[mechman]

My loft insulation is that good I now live in it

 

[zx9]

I put masses into mine when I did the loft conversation, My original house had barley 50mm. I went nearly 600mm in the side lofts of fibre, then 100mm of sellotex board in all the studs, top loft was also fibered to about the same then again boarded, walls were solid 9" typical 1950s which I skinned with 75mm fibre board then put shielded plasterboard on the top.

I have never once regretted going OTT on the insulation, It is such a tiny cost factored for 10-20 years over heating costs.

Iv just started on my new house a 3000 square foot 1800s brick stable block, I plan to rescreed all the floors and incorporate 50mm of insulation and UFH on the slab, then false cavity all the existing walls, I have yet to decide on max roof insulation because I want to have some beams exposed, however as I'm heating from biomass or GSHP on 40C water temps I want as much efficacy as possible.

When we had the loft conversion done three years ago I was amazed by the amount of insulation that went into the walls and ceiling, at the time I moaned about loss of head room. Now the loft is all warm and toasty in contrast to the the rest of the house, 1930's 9 and 4 1/5 inch brick with no caverties which looses heat like a wet paper bag.

 

[steveo3002]

added more to the loft when there was some special deal on , cant say what the bills are but its much warmer and well worth doing

 

[Burdekin]

Don't know but certainly helps keep home warmer.

We've got the Hive central heating control system installed and that's a revelation for us.

 

[brightspark]

Don't know but certainly helps keep home warmer.

We've got the Hive central heating control system installed and that's a revelation for us.

it works for some people especialy if your away from home a lot or come in at diffrent times-of the day . a few hours here and there soon mount up . im predictable so the boiler timer works fine for me

 

[Wedg1e]

I can't tell the difference and I've added three layers to the poxy bit of fibreglass that was in Wedg1e Villa when I bought it. I think it leaks through the windows, around the doors and through the walls so not sure I can criticise the loft insulation
My parents had cavity wall insulation added to their 3-bed semi and forever after the old man said he couldn't detect any difference in either the warmth of the house or the size of the bills. With the way the energy charges go up and down (well OK, mostly up) it's nigh-on impossible to keep tabs or work out a saving anyway.

 

[rtbcomp]

The re-introduction of the standing charge doesn't help, no amount of energy saving will reduce that. Mine went from 30p to 40p per day, whilst the unit cost went down a bit.

 

[addjunkie]

My place is an old stone farm house, when we bougt it, "i paid, she choose it, so its we". There was almost no insulation in the roof, concrete floors, and solid stone walls, rising damp, falling damp, and damp comming in sideways. All windows single glazed and siliconed up. A condensation dream.

It was impossible to get heat into the place, open fire, heating and aga on, still cold.

Now im broke, the house has 100mm kingspan in the floors, underfloor heating, and a poured screed over the top, wish id had it done in the shed too. Roof has 150 mm kingspan everywhere, then another 35 mil on the plaster board. All the outside walls now have 50mm kingspan on too. All a rated windows too.

What a difference, house is just under 3000 sq feet, we used 200 quids worth of oil and 3 ton of logs in 12 months. Lounge rarley below 18 degrees in the morning after 8 hours sleep. Only room we put the heating on upstairs is the bathroom. The other big difference i have noticed built a porch a year later, seems to have made the house warmer.

At the time it was painful buying the insulation, worse putting it all in. Nearly killed me. But long term worth every penny.

 

[malcolm]

Thanks all. I've been trying to tie in the SAP calculation with real life, and reckon loft insulation has made more difference than predicted. It seems there are better ways of calculation, but you have to pay people to do them. Secondary glazing and wall insulation to do next to keep building regs happy.

I think there is a lot in draft lobbies and porches, and putting unheated spaces outside heated spaces. Zoning heating is another favourite. I think that must be why the heating bills here were 1/4 of that predicted before any insulation at all (and less than neighbours with smaller and more modern houses). Although I find the neighbours houses far too hot which will be another reason.