Boosting energy efficiency status of buildings to combat climate change - what does it take?

frozen_wastes

zeupater wrote: »

Hi
Make a spreadsheet of what you can do, investigate the potential energy savings for each item (which will include relative heat-loss calculation & comparison), find out what each will cost and perform a simple ROI exercise on each sub-project ...

Regarding EPCs ... well, they're based on a set of completely dumbed down assumptions

Totally agree with all these points. If fact tonight I apply a can of expanding foam costing £5 to the gap between the outside edge of the floor and the outside wall underneath my kitchen cabinets. I've always had cold floors right were I'm preparing food, and sure enough there's a draught I can feel once I remove the cabinet skirting board. It probably also explained why there was always a faint musty smell coming from those cabinets (though no signs of mould anywhere).

It's an easy return on investment, with many other benefits. However I doubt it will move the needle much in terms of heating costs.

Draught sealing has some obvious candidates to address: Gaps under old doors and windows are obvious with much literature.

But there's plenty of other less obvious candidates:
- Pipe transits through floors and walls
- Cable transits through light fittings in the ceiling
- Cable transits through sole and ceiling plates inside stud walls whereever a light switch or socket exists.
- Cable transit in stud void where your consumer unit is located
- Skirting boards on outside walls could also probably do with a bead of silicone top and bottom.

I guess expanding foam and silicone sealant can address a lot of these gaps, and it's cheap.

I know about EPC's being very dumb. When I read the one for my house, it was a band F even though it had triple glazing and insulated walls, floors and ceiling. When I read the assumptions, it assumed there was no insulation in the floor, even though the space was fully accessible for inspection and anyone could plainly see the fibreglass insulation suspended in nets down there.

joefizz

frozen_wastes wrote: »

- Cable transits through light fittings in the ceiling

Wait until you seal most of the rest of the building to see how big a draught this can be! Or maybe its just you feel it more.


Similar position to yourself a couple of years ago, 80s timber framed bungalow built (or not built) to NI building regs.
I stripped it right down to the shell and made a lot of changes. I had originally intended in pulling off all the plasterboard to the external walls, breaking through vapour barrier and removing the 80s insulation (where fitted!) with modern insulation. Didnt bother in the end for a couple of reasons, primarily the absolute ball ache of doing this (needed building regs approval and got no sense out of them at all, 'you want to do what?'), inconvenience and the fact I was building an attached garage full length of the house anyway so probably wouldnt make that much difference.


A lot of it was simple stuff, when they had put the double glazed windows in they hadnt used filler in a lot of cases and with shrinkage there was just an airgap between inside and outside window sills in some places. Took that and the covers and internal sills all out, filled, plastered up and replaced all the window sills with internal wooden ones again. So if you are going to just put sealer top and bottom, take off and check for any gaps whilst you are at it. Some gaps are meant to be there but they can be filled with stuff other than air if you check ;-)



Took all rads off, cleaned, stripped, painted, cleaned through pipes (microbore - pita), fitted thermostatic valves to most of them. Insulated behind rads and put some of that shiny foil on, I know I know...


I travel a lot and liked the look of some of the way icelandic homes are done in secondary internal plywood square walls so did that on two of the remaining outward facing rooms. (wooden frame over plasterboard, insulation then plywood 'tiles' made nailed up and varnished - makes it look warm if nothing else.
I originally had only done this in the living room on the adjoining wall, primarily as soundproofing but it seemed to work well.



Took all ceiling coving off which was used to hide a multitude of cold breaks, sealed every single corner of every single part of every single room, sealed every gap above light fittings and cable access.



Similarly any electrical socket on an external facing wall was sealed up on the insulation side (was replacing them all anyway and fitting new ones)



Replaced thin insulation under the laminate floors with vapour barrier and 10mm of board insulation. All the skirting was taken off and at points I swear the draught felt like looking straight out into the street. Sealed all that up and skimmed the doors and door frames to accommodate. Left gap at bottom of plasterboard to floor but did use some non porous flexible fillings to cover up gap behind skirting.


I did leave the tiled bathroom and kitchen floors but as you mention the draughts coming in through service gaps was ridiculous. As was the gap under the double glazed back door, again, not filled, just covered with pvc trim! Be careful filling with expanding filler if you do this, close the door and dont use too much... ...just in case you bend the frame and can never open the door again. Similarly with gaps in windows etc, just be careful with the expanding foam, certain types from the builders merchants are best for this, not the diy sheds.


Went up to a minimum of 750mm insulation in the loft. I put a sealed storage area above one of the rooms accessible with another loft hatch and insulated above that as well so I have warm and cold storage areas in the loft (need to store moisture affected items at times).


I put in a drimaster for fresh air and had planned to go to a full recovery hvac system but didnt bother getting round to it. The drimaster also works in shoulder months when heat is in the loft early evening and pumps heat in. Only real problem I found out was that in dead of winter it was making me sick! Rel humidity was dropping below 40% and I was waking up coughing...


All of the above dropped my oil usage down from 1800 litres a year down to around 1000. (ofch and hot water).

The house isnt passive but last week the postman broke the insulated letter box and the draught racing through the house now is very noticeable, in fact this winter the letter box was the only real thing with condensation on it, so now its broke I might change onto a plastic one or just make the internal side out of wood (have some irish elm left over from the window sills).


I also have solar panels and a battery system so a month or so ago installed a cheap(ish) air source heat pump feeding the hallway outside hotpress, bathroom and office. Ive increased the insulation above the ashp primary path along the ceiling. Ive used this along with the battery to run it and the immersion in the last couple of months to cut down oil usage and am aiming for total use of 600 litres per year.
I think thats probably achieveable without any change in lifestyle. I have the bedrooms at lower temperatures anyway, bathroom is left free as it has the system overflow radiator anyway, I still have the big plasma tv in the living room so thats about 3-400W of heat output ;-)


Honestly Im well beyond the path of diminishing returns as I dont think its really that possible to retrofit without effectively tearing down and rebuilding. To get the level of wall insulation I really wanted there wasnt enough room in a lot of the walls so would have had to extend internally then hang plasterboard off that etc etc. I dont think building regs has a section for that ;-)


I just stayed with the double glazing I put in 10 years ago because it really wasnt worth the extra effort/cost. With the garage/reworking the garden theres only really two large outward facing windows now and with the possibility of a small porch/patio doors added to the recess in front of the front door that might take away a lot of that cold hitting the house. I also have plans to possible build a sort of greenhouse/lean to section on the back of the kitchen door/window and that will help also although the main driver for that will be if I can keep plants alive long enough to justify!
Increased fencing the back garden also keeps the north wind from directly hitting the back of the house now so again I dont know if that is just my wishful thinking or if it actually does make any difference but my thinking is that even a degree or so difference...
Above all else having done all of the above, if I knew then what I know now I would never have taken out the old wooden framed single glazing and replaced it with upvc double glazing. I dont think it was an option at the time (retail) to get double glazing units fitted to the wooden frames but now Id order them and do it myself.
I did look at making some secondary internal glazing, continental style, but in the only window it would make a difference (my bedroom, massive window) it would have impeded the fire escape window so didnt bother, thermal blocking pull down blind and then thermal lined curtains covering the whole gap will have to do. Ive also experimented this winter with the stick on plastic for a couple of windows. I did try this out once before when I had the single glazed wooden windows and it did make a difference, more for the draughts than anything else.



A good friend of mine has a passive house but it was built like that from the ground up. The windows and doors for their house cost almost as much as my house when I bought it in the mid nineties!


With the draughts etc its more about the feeling cold, we all get used to the temperature we are at (within reason) and when I got rid of all the access points (oh yeah chimney sheep up the chimney made a huge difference - without it, put feet up on the sofa all is well, put feet down and theres a cold chill circulating under it from the chimney).


Most of the things I 'fixed' were either down to shoddy original/later workmanship or just passage of time and probably fixing the gaps between window frames and walls and under back door were the majority of it. All really just cost less than about 40 quid for the whole house to put right, expanding foam, proper window sealant (not silicone, there are various types check with a builders merchant) and decorators caulk inside on the window sills and paying attention to cold bridges.

frozen_wastes

joefizz wrote: »

All of the above dropped my oil usage down from 1800 litres a year down to around 1000. (ofch and hot water).

installed a cheap(ish) air source heat pump feeding the hallway outside hotpress, bathroom and office...……………
Ive used this along with the battery to run it and the immersion in the last couple of months to cut down oil usage and am aiming for total use of 600 litres per year.

Now that's impressive just on the first count. I've now just finished with my expanding foam under the kitchen cabinets. A real pain to reach, so I doubled the length of the exp foam straw (leftover from last years can). Hope that will sort out the cold floor, but I'll get some rockwool slab insulation to put under the floor in that area just to be extra cosy (a bit thin the fibre glass around the edges of the floor).

I've definitely got a small gap around the window frames on the outside between the frame and the brick façade, so I need to seal that up for avoidance of rain ingress more than anything else (I doubt it'll help with insulation, since the wall cavity between façade and timber frame is probably ventilated.

Regarding building control, I am very surprised you need it to retrofit internal insulation. In Scotland, you don't need a building warrant (as it's called up here) for internal insulation - only external insulation application requires a warrant.

ajbell

What about micro generation?. I generate around 4.5 MWH a year and take only about 1MWH from the grid annually, I could be self sufficient with batteries.
Why not install Solar panels on every new build and bring back the FIT scheme to encourage others.

ajbell

Really interesting........https://m.youtube.com/watch?v=nWLzlrGGuxQ

Coastalwatch

ajbell wrote: »

Really interesting........https://m.youtube.com/watch?v=nWLzlrGGuxQ

Hmmmm! Think I'll give a miss, thanks all the same.:)

frozen_wastes

ajbell wrote: »

What about micro generation?. I generate around 4.5 MWH a year and take only about 1MWH from the grid annually, I could be self sufficient with batteries.
Why not install Solar panels on every new build and bring back the FIT scheme to encourage others.

Solar panels have been on my watch list for years now. The trouble is that I've never been able to make economic sense out of them. The best case has only ever been on of achieving a payback over a 17 year period, which to me is a marginal case, given the asset life of a system is about 25 years (assuming new solar tech doesn't make a 25 year old system look archaic)

Every time the panel prices drop, the feedin tariff dropped just as hard, if not harder.

So now we're in a phase where the feedin tariff is eliminated as well as the export tariff. Any surplus electricity generated may as well be curtailed, as perverse as that sounds, it's the same reward as exporting to the grid for free.

Now for business premises, particularly offices, I actually did a study on my employers office and I found opportunity for a 8 year payback because offices are occupied during the daytime.

But residential property has peak consumption in the evening time, so there's no merit for having solar unless you can employ batteries (very expensive) or fetch an export tariff (doesn't exist - not until the small export guarantee comes into effect anyway).

Already there's no economic case for residential solar (up in Scotland anyway), at least not this year. Nonetheless, I am expecting price of equipment to continue falling so I had hope.

But now we've got a proposal by HMRC to raise the rate of VAT on energy saving products from 5% to 20% effective October. Bear in mind that our gas and electric bills are charged at 5% VAT, it doesn't make for a level playing field.
https://www.solarpowerportal.co.uk/news/proposed_solar_and_storage_vat_hike_risks_setting_uk_decarbonisation_back_y

If that's not the last nail in the coffin for Solar, then the minded to decision for the Targeted Charging Review by Ofgem certainly would:
https://www.ofgem.gov.uk/publications-and-updates/targeted-charging-review-minded-decision-and-draft-impact-assessment
Have a read in particular for Annex 4.

Essentially it's a proposal to change our electricity bills from a usage based fee system, to a capacity based system (i.e. you pay for peak power, rather than how much overall electricity you use). If you use your oven, kettle, washing machine and other heavy consumers all at the same time - you pay big. If you use all of your heavy consumers just as much, but at separate times, you pay little! It essentially eliminates any financial benefit that solar power can offer, and it's a disincentive for investing in any energy efficiency measure as a whole. However household batteries could turn out to be very useful in this situation.

Add all of that together, and it would appear that government doesn't want the householder to be generating and consuming their own electricity. That evidently just upsets the status quo and they want us to continue paying ever increasing amounts of money to our utility companies as usual. I've written some words about that to my MP, as that really would slam the brakes on measures to decarbonise our energy model.

EricMears

frozen_wastes wrote: »

Solar panels have been on my watch list for years now. The trouble is that I've never been able to make economic sense out of them. The best case has only ever been on of achieving a payback over a 17 year period. . .

Be interested to hear just how many years SPs have been on that watch list ?

We started building a new house in 1997 and 'considered' fitting SPs from the start. However, with a payback period of 400+ years (NOT a typo - I do mean more than four hundred years) I'm afraid they stayed on our watch list until the FIT scheme was introduced.

We installed SPs on our (non-ideal) roof in August 2011 at a cost of £12,500 and had collected more than that by July last year which was approximately a 7 year payback.

We happened to have the cash available in a low-yielding ISA so bought the kit outright. Had we not, extending a mortgage at around 3% would have added £2,500 or so to the total so payback would have been postponed for approx. two years.

And of course we've still got 16 years worth of FIT payments to collect. Probably the best yielding investment I've ever made.

But it doesn't stop there - I haven't even tried to calculate the savings we've made in buying electricity. That's not easy to do as we've made other savings independently of self-generation but it's got to be around £200 per year from SPs.

frozen_wastes

EricMears wrote: »

Be interested to hear just how many years SPs have been on that watch list ?

It's been on my watch list since 2014. There certainly wasn't a 7 year payback back then (this was after the 41p/kwh feedin tariff), but it was the culling of the feedin tarrif from 13ish p/kwh all the way down to 4p/kwh that destroyed by plans in 2016. Equipment prices had been steadily falling, but when the tariff fell off a cliff like that, it was a very clear message that the government doesn't want solar to succeed at all.

We are where we are now. Still the vast majority of rooftops in both residential and business premises don't have solar panels. In spite of that, solar is providing 25% of overall electricity demand on a sunny mid summer noon so the potential for solar to expand remains huge. I would argue that it doesn't need support anymore, certainly not in the south of england. But barriers to installation such as VAT and targeted charging proposals need to be eliminated.

EricMears

frozen_wastes wrote: »

when the tariff fell off a cliff like that, it was a very clear message that the government doesn't want solar to succeed at all.

Or an even clearer message that the government realised the FIT scheme had served its purpose ?

frozen_wastes wrote: »

I would argue that it doesn't need support anymore

I think I'd agree (and I'm sure the government must).