Dr Hu

Pic Below - I know we have just had the coldest week of the year, and it IS January! - but sheesh!! - this weeks Smart Meter reading

Fairly modern (1990) 4 bed detached, Double Glazed, Deep Loft Insulation, new condensing Combi Boiler (Worcerster Bosch Greenstar CDi) - I mean what more can you do?
(apart from fit a Log Burner - hahahaha - how green! )
Heating set to 19 during the day, 20 in the Evening with a setback temp of 16.5

Try and make me feel better...

IdonthaveaScooby

Write a letter to NATO to curtail warmongering

I appreciate it’ll fall on deaf ears


otherwise, more layers

BMWhere?

Wow, that's a lot of energy! Is that your combined gas and leccy?

I have a high efficiency pre-fabricated house, heated to 22 degrees all day using an air/water heat pump. Total electricity consumption (for everything) for the week was 203.5kWh.

Weather wasn't great last week (a lot of cloud cover), so not much energy gain from the windows and the solar panels were covered with snow for two days, yet still managed to generate 28.9kWh of which of which 18.9kWh was self consumed and 5.1kWh was fed into the grid. So net total of 176.1 kWh grid supplied power for the week.

Note, the reason I keep the same temperature all day is to maximise the use of own electricity. If I let the house cool during the day and only heat in the evening, then there would be no self consumption during daylight hours so more or less 100% grid feed in, and then a surge of electricity after dark all supplied from the grid. As the buy back rate is higher than the feed in rate, its much cheaper if I use as much of my own power as possible. Also, generally warmer temperatures during the daytime mean the heat pump is more efficient. If I actually wanted to save, then it would be better to heat during daylight and turn the heating off in the evenings. Over night on the coldest days, I'd probably loose max 2 degrees!

Dr Hu

Yes - thats combined - the Elec was just over £20 - rest is Gas.... and you are not making me feel better - hahahaha

Richy P1984

Wow, I was feeling hard done by looking at £45 combined! That's with the thermostat set to 18 degrees for all on periods. Three bed semi 1950's concrete construction with NO insulation apart from the loft.

BMWhere?

Sorry!

However, interesting to see what a difference modern building techniques and technology can make! Assuming our non-heating consumption is similar, I'm using less than 1/3 of your total energy consumption and nearly 550kWh less on heating per week while keeping my house comfortably warm.

I know the costs of retro-fitting heating systems and solar panels is prohibitive for many, but if you can afford the investment, there are big savings to be had. The argument that it will take 20years to recover the investment is also not entirely correct as energy prices will only go upwards and typically at a higher rate than inflation.

ALi-B

iTrader: (1)

Yep you ticked the usual boxes... But HAVE you REALLY.


Double glazing. Yeah. BUT. Are they shutting tight (clue; hear traffic and wind? There's a gap in the seal). Argon filled units? Quality of thermal breaks in the frame (especially if aluminium)? Cold bridging via trickle vents in frame vs sash. Cavities closed and insulated around the frame? Same goes for doors and bifolds/patios etc. especially Juliette doors as they usually leak air between the two doors.

Guess what. My 5yr old windows had all these issues. Just replaced the lot (long story) with extreme scrutiny on the fitting and closing the cavities and insulation around the reveals (never trust fitters to do this). Difference is very noticeable. Also ditched those pesky trickle vents as I had MVHR so can still comply with building regs.

Attic insulation. What's the eave ventilation like?...is it letting a gale blow through up there? If you have Tyvec breather membrane under the roof tiles its probably over-ventilated. Any Dormas? Guarantee the nooks and crannies will be missing insulation.

Are your walls lined with plasterboard? Feel round sockets and switches on a windy day for draughts. You could be living in a plasterboard tent where outside air is circulating between the brick and plaster. From poor internal brick pointing, gaps around exterior waste pipes, dot and dab boarding etc. Or even the bricks themselves; Did you know breezeblocks are porous to air? Simple fix during construction of the house is to paint them before boarding out or plaster straight into the brick.

Any vaulted ceilings or flat roofs? If so make sure there are no flush fitting spot lamps in them, same with upstairs rooms with ceiling spots that vent into the attic. As they are a huge air leak. Unless they are IP65 and air tight (most aren't). I filled in all my upstairs GU10s and went back to surface mount ceiling lights.

Boiler. WB Greenstar, very good BUT is it set up right? Measure and regularly monitor the return temps. If return water is above 50C it won't condense and you're boiler's efficiency drops by about 10% (hence the adverts to tell you to turn down the flow temps). Aim for maximun flow of around 60-65C and return of 40 to 45degrees. Do this by system balancing on the rad valves and properly sizing radiators; Too much flow through small radiators or undersized will force you run higher return temps(always over-size). If you have thermostatic valves, if they aren't Drayton TRV 4s they are likely junk, or soon will be. If you have a mix of underfloor heating and radiators the boiler can short-cycle when just heating the floor, there is a engineer menu to adjust the cycling time and burner modulation rate to slow it from racing upto 60+C and shutting off, over and over.

Heating controls? Is it TPi? Better still, multi-zone, smart thermostats help here, but good quality TRVs can work just as well unless you want to vary a room temperature at different times or days of the week.

You can consider weather compensated controls, but I'll warn they can be an ****. This is my second house with WC controls (first one was a Honeywell AQ6000 that blew the mind of every plumber that tried messing with it). When set up and working right they can be very good, but if a room(s) has a higher heat loss than others, it needs oversized rads or extra insulation. As a WC system only drips in as much heat as it thinks the house needs, problem is most houses don't have an even heat demand throughout.

Also system condition; Magnetic filter? If no fit one. And use branded inhibitors. Some rads can sludge up in a little over 5yrs (mine were and that's a plastic pipe system so no indifferent metals). Feel for cold spots in the middle, that's usually a indicator of a channel(s) blocked up.

Alternatively knock the stat down to 12degrees and buy a battery heated gilet and socks; That's what I've been wearing at work as we have no heating (1960s single skin asbestos warehouse), absolutely ace (until the batteries go flat).

BMWhere?

I installed smart thermostats on the radiators in my old apartment, cut my heating costs by 40% and my apartment also felt warmer. The savings in the first winter covered the cost of the kit, very worthwhile investment.

Modern windows are now typically tripple glazed and also coated to let the suns heat in but block heat escaping. Biggest losses are the fitting seals around the frame. This is where pre-fab builds gain a lot of efficiency as they build the house around the windows which are delivered in advance so you get an optimal seal, rather than building an oversized hole and packing it out when the undersized windows are delivered later.

IdonthaveaScooby

We”ll all be living in Elons prefab containers sooner or later

he even puts his ole mum up with a mattress on the floor when she visits apparently

hedgecutter

iTrader: (5)

Can't cheer you up, as we installed a ground source heat pump in our self build barn conversion 2 years ago. Insulation exceeded all regs, achieving A grade EPC, and we qualified for the RHI just before the government stopped it. They pay us just over 1k a quarter, over seven years, so about 26 grand. So I haven't bothered to look what it costs to keep it heated 24/7. Sorry. But it's **** all anyway, and I get to spend the RHI on the car

hedgecutter

iTrader: (5)

Oh, did I say that we get to claim all the VAT back as self builders as well?

Dr Hu

Thanks for the replies everyone..... its a bit better so far this week, as its much warmer outside... so about half so far - which sort of shows my Thermal Loss must be quite large - we do have an open plan Kitchen Diner, with a 3 fold and a 2 fold Bi-Folds (with quilted pull down blinds) and a roof latern - I guess this is not great as its the coldest room in the house.
Thermostat is in the Hall, which I'd say is the second coldest place in the house.
I had raised the set-back Temp on the thermostat, as I read recently not to allow the house to go cold, keep it ticking over, the setback was 12c - so I raised it to 16.5c and heating comes on during the night at that temp, so the house is definately losing heat quite fast - I since dripped it again to 14.5 as I don't want/need the heating on during the night.

To answer AliB's comprehensive comments below (all appreciated by the way):

Yep you ticked the usual boxes... But HAVE you REALLY.


Double glazing. Yeah. BUT. Are they shutting tight (clue; hear traffic and wind? There's a gap in the seal). Argon filled units? Quality of thermal breaks in the frame (especially if aluminium)? Cold bridging via trickle vents in frame vs sash. Cavities closed and insulated around the frame? Same goes for doors and bifolds/patios etc. especially Juliette doors as they usually leak air between the two doors.
We have Double Glazing - around 25 years old - we have a couple of blown panes, and the exterior glass to frame seals are not great any longer - perished. We have a very solid wooden front door in a wooden frame with smallish single pane glass at the side - don't really want to fit a uPVC door, but appreciate the single pane glass panel is not great

Guess what. My 5yr old windows had all these issues. Just replaced the lot (long story) with extreme scrutiny on the fitting and closing the cavities and insulation around the reveals (never trust fitters to do this). Difference is very noticeable. Also ditched those pesky trickle vents as I had MVHR so can still comply with building regs.
Most of our older Double Glazing units don't have Trickle Vents, but the newer ones fitted more recently in our Kitchen Conversion does - they remain firmly closed!! No comment on the way they were fitted, but I guess from your experience not the best!

Attic insulation. What's the eave ventilation like?...is it letting a gale blow through up there? If you have Tyvec breather membrane under the roof tiles its probably over-ventilated. Any Dormas? Guarantee the nooks and crannies will be missing insulation.
Well - we had the standard yellow glassfibre sh1te about 10mm, but about 7/8 years ago we were approached by one of these Insulation Companies on behalf of the Govt and had deep wool insulation fitted for free (having young kids helped!) - which made a MASSIVE difference to the house warmth - really noticeable - the insulation fitters fitted polystyrene wedges between the tar sheets against the tiles, they said this was mandatory for good ventilation, however you can see daylight through parts the eaves etc when crawling around in the loft, the attic is always very cold (as you'd expect). We have no insulation bwteen floors (ie downstarrs ceiling/upstairs floor) and given the difference in warmth the attic insulation made, always wonder what difference insulation would make here, but what a massive job to retro-fit!!

Are your walls lined with plasterboard? Feel round sockets and switches on a windy day for draughts. You could be living in a plasterboard tent where outside air is circulating between the brick and plaster. From poor internal brick pointing, gaps around exterior waste pipes, dot and dab boarding etc. Or even the bricks themselves; Did you know breezeblocks are porous to air? Simple fix during construction of the house is to paint them before boarding out or plaster straight into the brick.
Yes we have plasterboard (modern house construction - dot n dab plasterboard on exterior walls, stud wall./cardboard waffle interior walls) - I've never really noticed drafts from sockets, but is something I will investigate - we do have a Letterbox DRU Metro gas fire let into the chimney breast - you can feel noticeable drafts around this, but I think this is by design for regs/ventilation?

Any vaulted ceilings or flat roofs? If so make sure there are no flush fitting spot lamps in them, same with upstairs rooms with ceiling spots that vent into the attic. As they are a huge air leak. Unless they are IP65 and air tight (most aren't). I filled in all my upstairs GU10s and went back to surface mount ceiling lights.
We inherited 6 x MR16 Halogen downlighters in the Landing Ceiling which almost certainly leak air into the loft. open backed - I have changed half the bulbs to LED, and are considering some Thermal Hood type things to cover them in the loft, as currently they have a a foot square hole round each one in the insulation to prevent overheating. I know this is not good!! I hate them anyway, especially being MR16!!

Boiler. WB Greenstar, very good BUT is it set up right? Measure and regularly monitor the return temps. If return water is above 50C it won't condense and you're boiler's efficiency drops by about 10% (hence the adverts to tell you to turn down the flow temps). Aim for maximun flow of around 60-65C and return of 40 to 45degrees. Do this by system balancing on the rad valves and properly sizing radiators; Too much flow through small radiators or undersized will force you run higher return temps(always over-size). If you have thermostatic valves, if they aren't Drayton TRV 4s they are likely junk, or soon will be. If you have a mix of underfloor heating and radiators the boiler can short-cycle when just heating the floor, there is a engineer menu to adjust the cycling time and burner modulation rate to slow it from racing upto 60+C and shutting off, over and over.
I have it set to a pretty low flow temp - against the 'e' stop on the temp control which is around 50-55c - I don't have a suitable pipe thermometer to use to check flow temps - we have a mix of rads, double plate rads in the lounge, which gets toasty as soon as you shut the door, and modern upright ali rads in the new kitchen/hall - upstairs are all boggo single panel rads on small bore pipe (yuck) - they do all get hot though, and are well bled, and balanced as best as possible. We do not have ANY TRV's apart from the 2 new rads fitted in the kitchen - do you think this will make a big difference?

Heating controls? Is it TPi? Better still, multi-zone, smart thermostats help here, but good quality TRVs can work just as well unless you want to vary a room temperature at different times or days of the week.
with the newish boiler we had a ESi Heating Thermostat in the hall (not smart) - its quite good, and does TPi, OST etc which are all set, however I read recently that WorcesterB doesn't accept OpenTherm commands - I believe they use proprietry - I did consider upgrading to the WB Weather Compensation controls, but as the flow rate temp is pretty low anyway I did wonder how cost effective this would be - as this is quite expensive to fit. to fit a Smart Thermostat with Smart TRV's etc is quite an outlay, and we have pretty 'fixed' periods of house occupation that doesnt really differ, so question the need for a App controlled heating system.

You can consider weather compensated controls, but I'll warn they can be an ****. This is my second house with WC controls (first one was a Honeywell AQ6000 that blew the mind of every plumber that tried messing with it). When set up and working right they can be very good, but if a room(s) has a higher heat loss than others, it needs oversized rads or extra insulation. As a WC system only drips in as much heat as it thinks the house needs, problem is most houses don't have an even heat demand throughout.

Also system condition; Magnetic filter? If no fit one. And use branded inhibitors. Some rads can sludge up in a little over 5yrs (mine were and that's a plastic pipe system so no indifferent metals). Feel for cold spots in the middle, that's usually a indicator of a channel(s) blocked up.
Fitter fitted a Mag Trap on the new boiler, and its cleaned/serviced every year - all the rads get piping hot

Alternatively knock the stat down to 12degrees and buy a battery heated gilet and socks; That's what I've been wearing at work as we have no heating (1960s single skin asbestos warehouse), absolutely ace (until the batteries go flat).
I can vouch for a heated Gilet - we bought some last year for use outside and OMG!! Game Changer! highly recommend to anyone who gets cold - hahahaha

And Lastly - hedgcutter - I remain unconvinced of the benefits of ASHP or GSHP - considering electricty is like 4 times the price currently of Gas.... its going to be a hard sell to the General Public - I don't think I've yet heard of anyone being truly happy with a ASHP... but have heard some absolute horror stories costing some a LOT of money. Considering a Gas Boiler is circa 2 to 3k fitted - but a ASHP can be 11-12k plus rad requirements costing more.... its going to be a hard sell! - unless like BMWhere where you generate your own power with battery storage - but thats adding yet another 20k to the 12k ASHP anyway - plus good quality building quality/insulation/PassivHaus standards, which we all know are virtually unknown the UK it's all getting rather expensive for Mr Joe Soap....

hedgecutter

iTrader: (5)

Totally agree with all that. Building from scratch, I've had to guess what might be best in 10 or twenty years time, and gas wasn't an available option, even tanked. At least I could insulate the nth out of it, and will soon be able to generate and store electricity. This barn is listed, so the heating system was only a small % of the huge costs involved, and ufh is undoubtedly the best system for a granite barn with porous walls.

EddScott

When it's very cold, our monitor thing will sail past £100 a week no problem. My house is famously cold (within the family anyway)

House isn't big per se, but rooms are big. Attic conversion has been done but don't think there's much in the way of insulation up there.

It doesn't help though that we're on Octopus Intelligent and the monitor doesn't report the right cost when the car is on charge. Fortunately, the actual bill isn't quite as bad as the monitor makes out.

BMWhere?

Was having a chat with a colleague who's other half is a green energy consultant about setback temperatures.

The theory is, if you heat with a heat pump, you shouldn't setback at all as heat pumps are good at maintaining temperatures, but not good at full on heating, so high demand after setback reduces the efficiency of the heat-pump.

For Gas/Oil heating, setback is desirable for efficiency as you can heat back up pretty quickly and losses decrease as the temperature falls. However, there is a critical point where the building starts to cool. Heating air requires relatively little energy compared to heating the building. Initially during setback, only the air is cooling and the building retains its heat. Once the building also starts to loose heat, then this will require a lot more energy to get back up to temperature than just re-heating the air. The general consensus for optimal efficiency is around 17-18C. This is the same temperature which was recommended for my smart radiator valves in my old place.

ALi-B

iTrader: (1)

Sorry for late reply, my head got totally frazzled last week by the gaffer at work for giving me a successionof jobs that "hAd BeEn To OtHeR gArAgEs WhO cOuLd'Nt FiX iT! Not helped with some of them being Land Rovers. 🤯







Bifolds can be quite leaky, especially across the bottom and on the end that open. Ours had a totally flat, zero ridge threshold so no rebate to close against and they used a thicker brush gasket to compensate, which seemed ok, but blew through under pressure when it was windy. The replacements have a raised ridge on the threshold to to shut tight against.



Roof lantern suggests a flat roof. It maybe insulation has been missed in areas. Especially if they used celotex. Builders have a habit of not cutting it very well and leaving gaps (they should fill gaps with expanding foam).





Modern glazing is alot thicker. At that age I'm going to guess the hinges are going to be worn and results in the window not pulling tightly closed at the hinged end. My mums old house had similar age PVC windows which were ok, but had to have nearly all hinges replaced as they had dropped (catching the frame when closing) and weren't pulling closed tightly. Reduction in outside noise before and after was noticeable. Hinges and seals are alot cheaper than new windows.





The problem with most trickle vents is they are often cut into the hollow sections of the frame, and as they only shut on the inside, outside air can still circulate inside the frame making the thermal break pointless (especially if frames are aluminium). They also allow air to flow in either direction, when really it should be one-way depending on room use; To let stale/damp air out of bathrooms and kitchens, and allow fresh air into living and bedrooms; You don't really want damp air in a bathroom being blown into the rest of the house. Plus no control of excessive airflow rate on windy days; It really is crappy design that nobody in the industry has properly addressed and building regs seem to cause as many issues as they solve. Except mechanical ventilation, which isn't cheap as a retrofit. But good (as in powerful) extractor (to outside) in the kitchen and bathroom (switched by light on timer) should be enough to negate trickle vents so long as they are not the naff asthmatic 4" Marley "Part F" trade counter fans that the average builder/spark uses which does nothing but make a lot of noise.









Sounds like they did it right. The old tar felt doesnt breath. So does need more free air than the newer breathable fabrics. The eaves and soffits will be vented which will be where the daylight can be seen. Not much can be done but ensure that air doesn't get though to the downstairs like holes in the ceiling for lights etc.



Insulation between floors in contentious as some argue it heats rooms above and aids ventilation blah blah. I did it as I moved from a dorma bungalow that desperately needed insulation between floors as the eaves basically vented through the downstairs ceiling and it had terrible soundproofing between rooms (since found out I have hyperacusis). So when I had to re-floor the house I moved to due to floorboards being wrecked by previous plumbers/sparks, I insulated between floors for both heat and noise (kept about 1ft away from exterior walls to protect joist ends just case of damp in brickwork).



Ground floor insulation is probably of more benefit if it's a wooden suspended floor. There was a period in the late 80's and early 90's builders dabbled with polystyrene backed floorboards, so it may have them but I think it fell out of favour as it can be creaky.







Yep its regs. Open fires and stoves that use room air for combustion need to have a unrestricted source of outside air. I have vent in the wall that lets a gale through as its located by a alley that funnels the wind through it. Between you and me, mine has a bag of wool insulation shoved behind the grill. Have a working CO detector/alarm in the same room, plus have the sense to crack the window a bit when I use the fire (which isn't often). Alternative is you can get fires/stoves that can directly draw air from outside negating the need for a fresh air grille it's possible your fire may have some sort of outside air supply built in.





Swap the fittings for IP65 ones (fire rated). They are air tight (have a glass cover/bezel). The hoods are ok, but seem a bit expensive for upside down plant pots and you still have to glue/seal them to the ceiling and somehow seal around the wiring which is probably looped in and out of each fitting.







TRVs in unused rooms or rooms that get too hot will help especially if the heating stat is in a cold room. Cheap ones don't work for long as they either stick closed over summer or become "all or nothing" as they age.





WB still not using opentherm is an ****. Their own controls are quite good though but last time I checked were a bit behind with the smart stuff.



Weather compensation I think is hit and miss. The logic is simple enough; Colder outside = Higher boiler flow temp. Most heat pumps use it, mine is based on a REGO1000 (whatever that is), which to be quite frank is a unituitive pile of crap to configure as it is not self-learning, so took two winters to get the heat curve (flow temp vs outside temp) dialled in so it didn't over-use the heat pump or under-heat. Previous house had a Honeywell system that despite being ancient was self-learning and to the user just worked like a normal programmable room stat.



Ok, I have massively oversized radiators and underfloor heating, but to maintain my house temperature at approx 21C the flow temp doesn't go above 30degrees C unless it's below freezing outside.



So there has to be a energy saving advantage to be able to automatically throttle the boiler's flow temp during warmer days.



Smart controls are a half way house. Probably a bit pointless on a single zone heating system. One distinct advantage is the ability to set-back the heating based on your phone's location. Or turning off automatically when it's warm outside. And programming timers/temps from the comfort of your sofa instead of poking the thing on the wall in the hallway whenever you want to change a setting.



I did have a Honeywell Evohome which was very good except the BDR91 relay units that started to die and lose communication and Honeywell/retailers doubling down and blaming the installation; I think the internal PSU degrades and creates radio noise, meant to convert them to external power to test my theory, but never got round to it.



Currently using a Heatmiser Neo zoned smart heating (to control set-back - I leave heatpump to do its own thing and heat a buffer tank that each zone taps heat off as and when). It is a lot more robust. But not TPi, and the room stats are the 240v version with a built in power supply...that self-heats the temperature sensor Had to modify the wall plate to fix it. If I'd known I'd have bought the low voltage versions which have a remote power supply.











I have a GSHP. Inherited. Badly installed. Badly configured. Air locking. Tripping overheat alarms etc. I've completely re-plumbed everything and after hours of head scratching over installer manuals originally written in Swedish then probably translated into German before English, configured it. It's now ok. Average electric use during Dec/Jan is about 38kw/h a day ; That's for everything; heat, hot water, cooking and lighting.



So they can work, but they must be used as part of a whole-house solution. Many are just being plonked into houses with insufficient/bodged insulation that needs completely re-plumbing. And a alternative energy system (PV and/or battery on Eco7) to help with the leccy costs.



Return on investment is the killer for most home improvements. OK I'm probably saving £1k a year over gas/oil. But the payback time to cover the costs involved if done by "professionals" is going to be best part of a decade. I don't care; I gained the heat pump and DIY'd a lot of it and don't intend on moving ever again.



FWIW I was quoted over £50k for exterior wall insulation! Not being funny but it's just cladding the house in polystyrene then spraying on some textured render; How does that cost £50k? There is no way I'd get any saving return on that kind of expenditure. Goes to show what sharks exist in the "eco" sectors; A full PV and battery install would cost a quarter of that and give far more energy saving and return on investment.

hedgecutter

iTrader: (5)

Just to add to that, our annual usage is around 3000kwh for a 100m2 ground floorplan, ( 3 floors) so the heatpump is actually very effective.......in a ground up build with maximum insulation. So obviously not relevant to you, but as Ali has shown, correctly installed, they work very well. I believe the capital cost will be covered when it's sold, because it's efficient in comparison with equivalent local properties. Insulation is everything.