[Closed] Govt Green Energy Giveaway - what to get?

I wouldn’t get too excited until the scheme is laid out in full. Boilers may not be covered according to Martin Lewis.

https://www.google.co.uk/amp/s/www.moneysavingexpert.com/news/2020/07/homeowners-to-receive-p5-000-vouchers-to-improve-energy-efficien/amp/

We don’t have cavity walls. Has anyone had exterior insulating fitted to their walls?

I fitted interior insulation to our bedroom. Only 50mm of cellotex and only one wall but it has made a huge difference. Used to be really cold in the morning, but now it is pretty pleasant. Would ideally do the whole exterior but that is a massive job and I doubt we would see any kind of payback

Even with the gov grant you'll be looking at a multiple of a new tank to fit.

Fwiw I had a new harlequin 1400l bunded tank with outlet and apollo monitor system delivered for 1350 quid last week.

Even if it is 500 to fit it.....it'll still be less than a good sized heatpump.

Running costs of heat pump unless you have the perfect location that gets good sun all day long and you don't have extended periods below zero ......and the green party will be along to say I'm wrong how ever based on experiences of those I know with brand new houses who have had heat pumps forced on them......I'll not be rushing for that technology any time soon not least till the bulk of my electric is self generated

I'm going for insulation instead. 100 mm exterior insulation with cedar or larch cladding over the top.... Still be multiples of the tank to buy and fit mind.

@trail_rat, I like the idea of wood cladding over external insulation but can't find a lot of details as to how to do it - most websites for external insulation just render. Can you point me at any good sources?

Don't suppose this will cover solar panels, will it?

I fitted interior insulation to our bedroom. Only 50mm of cellotex and only one wall but it has made a huge difference.

Hmm, interesting, tell me more...

My brother swapped from oil to air source heat pump a while ago now and after a few teething troubles were fixed he has liked it. You need big rads and run it longer though as the water doesn't get as hot as from a boiler.

A house in my street did external wall insulation a few years ago. Looked a massive job, but looks very smart. It's hard to tell it's been done, just the deeply rebated Windows as a clue really. It must make the house feel much more comfortable but on cost alone it's payback would be a couple of decades at least without the grant, probably still many years with. Worth considering if planning to stay in the house a while perhaps.

Don’t suppose this will cover solar panels, will it?

If replacing an oil boiler you may get best value from installing a biomass boiler and claiming running costs through the renewable heat incentive.

There is a calculator on the government site so you can see how much you might get for heat pump or biomass boiler.

https://www.gov.uk/domestic-renewable-heat-incentive

There is a debate as to whether biomass is truly 'green' but if replacing an oil boiler the answer is almost certainly massively more green.

Trail rat - this idea starts with replacing the existing tank (2,500ltr) and moving it, so we recon approx £2.5k

I know heat pumps would potentially be approx £15-20k but we would see it as a long term investment.

But if they are not that great then no point switching !

Which would give the best long term benefit?

The best bang for your buck will pretty much always be insulation of some sort.

It's cheaper to retain inefficiently produced heat than it is to produce heat efficiently and piss it out into the environment.

They can be good.

You need to find a good heating engineer who is honest and not just going to sell you the dream.

They are not applicable to alot of situations/locations.

Unfortunately many folk want them hidden out of view and for that it often means shaded cool spots and it's just making life difficult for them.

Ask somafunk how his air - air heat pump is for example.

As for insulation and cladding..... The mechanics of it I'm not exactly sure of. Give me 4 weeks and I'll let you know. What I do know is there's a sodding expensive breathable membrane involved.

It's not cheap sure but like you I'm looking at the bigger picture long term and doing this means my produced heat which largely comes from wood anyway is retained longer. As it is 1400l of oil will last me 2 years maybe more. My old tank was only 1200l and that's before insulation. We are just twin leaf rendered cavity wall with plaster direct no insulation so this will be a massive improvement. Not passive haus at all as the construction means ventilation must be maintained to sub floors and eaves but gains are gains

Agree with Perchypanther.

I spoke to a mate who does energy modelling for buildings. He says that in every job he’s done (ranging from wee cottages to big offices) stopping heat from getting out is the number 1 recommendation.

I would second the need for a genuine specialist to do the job but certainly a good heat pump installation should work absolutely fine. What the installation actually is depends on the house though - underfloor vs rads? How good is insulation? Air tightness? As noted above, a general rule of sorting your heat loss first and your heat source second is a pretty good one. We are installing a heat pump in a 70s bungalow at the moment but have worked hard on insulation first, which we could do because it's part of a bigger renovation.

Heat pumps shouldn't really be considered in isolation, radiators are a bodge really as they are more suited to running under floor heating which is, again, more ££££. Same with trail_rats problem, if you don't have a decent amount of land or the right sub-surface conditions then you need a 100 odd metre borehole which is, you guessed it, more ££££. It's not really something suited to retrofitting unless the house is REALLY worth it.

Can you cover external insulation with wood? I'd have thought that would be a massive no due to fire regs since it's just sheets of polystyrene/pu. I know regs are different to flats/hmo's but still.

Can you cover external insulation with wood? I’d have thought that would be a massive no due to fire regs since it’s just sheets of polystyrene/pu. I know regs are different to flats/hmo’s but still.

How do you think they build wooden clad houses.

It's about using the right insulation. ....hence the spendy membrane required.

My building warrents been approved and all the work and specifications are detailed on the architects drawings

I'd also assumed air-air heatpump.

I'd have a borehole all day long if I had the money. Geothermal heat source of you have the geotechnics for it is the tits.

Can you cover external insulation with wood?

It depends...but in geeneral term, yeah, you can, but it'd only be for aesthetics.

I’d have thought that would be a massive no due to fire regs since it’s just sheets of polystyrene/pu.

Not all EWI is EPS. Almost all of the systems on the market are extensively tested for fire performance.

I know regs are different to flats/hmo’s but still.

Have a look out of your window. If you can see a block of high rise flats, then there's a fair chance it has EWI on it and that I put it there.

Don’t suppose this will cover solar panels, will it?

You don't want to do that - sunlight won't get through if you cover them.

yeah, you can, but it’d only be for aesthetics.

Exactly why I'm doing it. Ties in with my extension work.

The only place- I'm.not allowed to do it.....or externally insulate is behind the oil tank and boiler.

We get through 2500 ltrs in less than a year! It is a fairly big house. I did a load of insulation work before last winter, which did make some difference, but there are some roof spaces that you can not get access to.

The house is also built directly on to limestone rock with very thin soil layer so I doubt heat pump Would work ... apart from drilling a very big hole

It’s cheaper to retain inefficiently produced heat than it is to produce heat efficiently and piss it out into the environment.

Ooh, get you and your 'science'.

FWIW, hopefully Rishi will bung us a few quid to insulate the loft properly.

FWIW, hopefully Rishi will bung us a few quid to insulate the loft properly.

You'll need to pay a third of the cost of the work which will be by a list of approved specialists, who will be tearing the arse out of it.

I fully expect the eligibility for the grant to be means tested and that your average STW'er won't qualify.

It likely won't be much different in practice than the various existing schemes that have been in operation for the last twenty odd years ( 12 of which i spent working for specialist contractors who were tearing the arse out of it)

They were great schemes for the people who genuinely needed them because they lived in substandard housing.
They were never really designed for the middle classes to install geothermal and solar panels in their 4 bed detached villas. I don't imagine this next scheme will be any different.

by a list of approved specialists, who will be tearing the arse out of it.

my experiance last time round.

The only thing that would have been funded with any adequacy was if i was willing to let them drill heaps of holes and fill the cavity .....

of course in a highly exposed and wet area that is ill advised - it didn't stop them with the hard sell though.

basically anything that comes with gov funding can almost always be done cheaper by local contractors.

roof spaces that you can not get access to.

whats your wall construction? any gains to be made on insulation of walls. Uk on the whole are pretty poor at this.

Uk on the whole are pretty poor at this.

You're in Aberdeenshire, right?

Have a look out of your window. If you can see a council house, there's a fair chance it has EWI installed and that I was inv olved in putting it there. 😉

i live in an (ex) council house. perchy .... but the only thing i can see from its windows is a horse stables. Cooncil came round and blew insulation into the arse of some of the neighbours houses that are still council....thats why i know it doesnt work here.

thats why i know it doesnt work here.

It doesn't really work anywhere ( unless it was designed and built in as part of the new build)

When I was on the EWI treadmill, we had an entire department dedicated to removing cavity wall insulation so we could install the EWI afterwards.

i saw it in Arbroath ..... external insulation and render on cooncil hooses in Charles avenue.....

thats why im not externally cladding and rendering. .... i think it looks ruddy awful - but i do get that isn't the point on a council house. the deep reveals and the not moving exisiting wall furniture such as gas boxes / waste exits and soil stacks ..... just leaving cut outs.

Im hoping the wood lets me deal with the detailing better.

- im guessing that wasnt in your remit 😀

the deep reveals

An unavoidable downside of increasing wall thickness by 112mm....unless you use phenolic insulation which gives you, roughly, the same u-value for a board that's only 40% as thick. Spendy though.

and the not moving exisiting wall furniture such as gas boxes / waste exits and soil stacks ….. just leaving cut outs.

– im guessing that wasnt in your remit 😀

In order for the councils to qualify for the funding for a property they only needed to insulate 80% of the external wall area. We always offered the option to move gas boxes, extend flues and services and all that. That obviously carries a cost and many councils only care about how many properties they can do.
By missing all the nice bits out they were probably able to do 20% more houses.

It can look great if it's done well but, crucially, can still be brutally efficient if it's done half-arsed.

An unavoidable downside of increasing wall thickness by 112mm

Without doubt.....and who knows maybe my thought process on the wood clad looking better than render is wrong....I just think I'll be able to hide more sins than if it was masses of concrete 🙂

I fully expect the eligibility for the grant to be means tested and that your average STW’er won’t qualify.

all the initial stuff seems to say every household will get £5k and poorer ones £10k so fingers crossed!

Depends on the prices the gov approved contractors charge though if its worthwhile or not.

all the initial stuff seems to say every household will get £5k and poorer ones £10k so fingers crossed!

I admire your optimism in the face of overwhelming evidence of the Government consistently under delivering on all the good stuff they promise in the future.

And it's not £5k. It's partial funding (two thirds) of £5k of works so, about £3,333. You need to pay the other third yourself.

I fitted interior insulation to our bedroom. Only 50mm of cellotex and only one wall but it has made a huge difference.

Hmm, interesting, tell me more…

The room has two external walls, one with a bay window, no cavity. It has traditionally been pretty cold but very noticably on the external wall without a window as that has the bed against it. When we redecorated (to get rid of the lovely red walls!) I put up three sheets of insualted palsterboard. It was quite a good fit so only had two joints and not much cutting and filling. Its been up a good few years now and it really has made a big difference. Touching the wall before in winter it felt like an ice block, now it just feels like an interior wall. Well worth doing and not much cost or effort. Ideally I'd do the bay too but that is 10x more work for a tiny gain, it is so much better now that I'm not too worried about doing more.

[img] [/img]

How do you think they build wooden clad houses.

I just assumed the insulation was mounted to the inner skin as per mine (albeit mine has a block outer).

With you on cavity, we got it done, dunno what difference it made. Didn't feel any different especially with the 100mm dia hole they drilled in the wall for the back boiler.

I like the idea of wood cladding over external insulation but can’t find a lot of details as to how to do it – most websites for external insulation just render.

loads of houses in Cambridge seem to be getting external insulation, they do a pretty impressive fake brick covering as well...

Its petty impressive, once done you can only tell by the extra depth around windows etc.

[url= https://live.staticflickr.com/7486/16190586106_9fe02c0704.jp g" target="_blank">https://live.staticflickr.com/7486/16190586106_9fe02c0704.jp g"/> [/img][/url][url= https://flic.kr/p/qEGZbj ]External Insulation[/url] by [url= https://www.flickr.com/photos/brf/ ]Ben Freeman[/url], on Flickr

[url= https://live.staticflickr.com/5470/17676765655_36bf85caa8.jp g" target="_blank">https://live.staticflickr.com/5470/17676765655_36bf85caa8.jp g"/> [/img][/url][url= https://flic.kr/p/sW33zD ]Brick and Render External Insulation[/url] by [url= https://www.flickr.com/photos/brf/ ]Ben Freeman[/url], on Flickr

I just assumed the insulation was mounted to the inner skin as per mine (albeit mine has a block outer).

but even then - in a structure thats internally and externally wooden (wooden frame , clad with wood with insulation inside) its still the same fire risk. if nothing else at least my having the bricks between me and the Flammable stuff gives me half a chance.

The problem with internal insulation for me is if it drops the dew point to being within the wall. My house is 1960s timber framed with a brick skin - I really don't want to let the timber frame get wet.

if nothing else at least my having the bricks between me and the Flammable stuff gives me half a chance.

Yep Cellotex is supposed to be extremely toxic when burnt, some Cyanide derivative gas...

if nothing else at least my having the bricks between me and the Flammable stuff gives me half a chance.

In a structure with timber and insulation it's pretty much always going to be the timber that that's the fire risk.

Most EPS boards contain a fire retardant chemical which causes them to melt under extreme heat rather than ignite. Mineral fibre boards, which is what all high rise EWI should be done with are about as flammable as a piece of granite

The problem with internal insulation for me is if it drops the dew point to being within the wall. My house is 1960s timber framed with a brick skin – I really don’t want to let the timber frame get wet.

Any competent contractor will get the system manufacturer to provide an interstitial condensation calculation to inform the spec and prevent this happening.

In a structure with timber and insulation it’s pretty much always going to be the timber that that’s the fire risk.

Indeed the fire will burn up to my asbestos eaves 🙂

I have an air source heat pump which was installed when we rebuilt the house from 4 stone walls. We built an insulated box inside the house and spent a fortune on insulation. The ASHP replaced what would have been oil heating but at the time, oil was well over 45p a litre I think. Bit cheaper now.
We get the 7 year govt green energy payment 'thing' which covers the cost of the installation and a little towards monthly cost of running it.

As someone else has mentioned, it works well as a secondary source of heating and indeed, we have an aga on the Economy 7 tarrif which heats the house year round. It is a very rare occasion that we even have the heating on. We also burn wood in preference of having the heating on as well. It heats the hot water tank in no time at all though - about 1.5 hrs max. But again, this is set to happen during the night on Economy 7 tariff. Switching to that would be worthwhile I reckon if you were seriously considering doing it.

If you can get mains gas then our calcs suggested the cost saving was minimal but a definite saving over oil (at that time). At the moment I'm not sure it's the same cost differential but it is easier to budget if you're not at the mercy of oil price fluctuations...

Horses for courses, in summary!

As lots of others have said, insulate before you upgrade any heating system. It's like if you had a leaky pipe, you would find the leak and fix that first instead of increasing the flow of water.

The other thing is you will all get some good general info and anecdotal stories on here but every house has a different context. Almost every house will require a different specific insulation and heating system which is best for that house. The best way to do that is to get a consultant to do a survey on the house. I really think the best advice you'll get here is where you can look to find the right information about your house.

Regarding the external insulation and using timber cladding. I've really never understood why so many people are adverse to using timber in the UK. I guess it is just less common throughout history so people are more untrusting of it. But head to Scandinavia and you'll find the majority of houses built from wood. They aren't all burning down every week, nobody is worried about their house going up in flames. Yes wood is flammable (as are many other things like all your belongings inside your house) but there are standards in place to reduce the risk of fire spread.

Trailrat - the part I would be interested to see the detail for on your timber clad external insulation is where the walls meet the roof. Often there's not much overhand on the roof so, usually none on the gable end meeting the roof, so how are they accounting for covering the new thicker wall at the top?

Someone asked about the construction of that. It could be as simple as: timber studs fixed into external wall, insulation between studs, breather membrane (which is essentially a Giant Gore-Tex, might explain the cost Trailrat 😉 ), then vetical or horizontal batons to fix your cladding on, cladding. The main thing is stopping moisture building up in the wall so that means speccing the right materials and thicknesses to stop the dew point being inside the wall and allowing any moisture that does build up inside to breathe (hence breather membrane).

Quite interested in this kind of thing so thought I would give some random points I thought after reading all of it. Hopefully some small things are useful to someone :).