Leaderboard

Today was a big day for any self builder. The day the second most important bit of paper ever arrived, the building control Completion Certificate (The most important bit of paper being the granting of planning permission) This “ends” a long chain of events that has taken way longer than we ever expected. It all started in October 2013, that’s a staggering 8 years ago, when we completed on the purchase of the building plot, though it was at least a year before that we started looking for a plot. Construction did not start in earnest until Spring 2015 when the final design, planning and building warrant was in place. Construction started well with a local building firm contracted to do the foundations and build and erect the timber frame. But that all ground to a halt by Spring 2016 when it became clear there were no buyers for our old house in a stagnated housing market and we had to terminate our arrangements with the builder, thankfully on good terms with them. Since then it has been a slow “build as you earn” self build doing way more of the work ourselves than we ever expected, and building to what turned out eventually to be a very low cost, and somehow against expectations, we finished the house that we could not afford to build. The VAT reclaim was paid out a few weeks ago and that paid off some interest free borrowing we had accumulated finally leaving us with no debt and a very modest amount of savings left. Phew. The house is about 150 square metres in total floor area and the final build cost has come in just a shade under £1000 per square metre not including plot price, services and professional fees. So now the house is “completed” does that mean we are “finished” No of course not. Some things have been left out for now and some not fully completed. So our “to do” list still includes the following: Bedrooms and stairs still need carpets and most rooms still need curtains or blinds. An airing cupboard needs to be formed around the hot water tank and we might still build the pantry in the corner of the kitchen. Outside there is the balcony still to build, some decking and paving, at least one more shed, a bridge over the burn, the car port and the tarmac entrance still needs it’s top coat and some drainage installing. Then there is fencing and making something of the garden. So at least another 2 years work to “finish” which will make it into a 10 year project. No I would never have believed at the start it was going to take that long, and it was not until I typed this and looked up the dates that I realised we had been working on this for 8 years already.

Wow that took me a long time, what a difference a year makes! I did always know that it was going to be a difficult room to do, and also the largest in the bungalow, but I have reached completion, apart from the carpet which is on order. So firstly there was the repair to the area under the window, which needed the brickwork rebuilding and then replastering... Next I started work on the acoustic wall, comprising of a metal framing system filled with Ultrawool, sheeps wool insulation, and topped with a soundblock 12.5mm board, no photos of the wool, as it was a bit of a battle to keep it in place ? After all the planning, the old chimney breast for my media kit was looking rather tight, but luckily tape measure didn't let me down! All painted up... Gypsum cladding installed, alcoves painted, and TV installed... And finally, window reveal and window board painted (window board at the moment is just the ply holding the bow window up, as at some point (maybe next year) this window is being replaced with a 3G flat window, so this will be removed), curtain pole and radiator reinstalled... Will put a final photo up once carpet is in and all furniture is back. What a push all that was!!

Welcome. There is an easy answer 1 and 3/4 hours. The better answer is to understand what it all means. I shall start with the ASHP power, the 5 kW (that is lower case k for 1000, and upper case W for watt, watt is lower case, unless at the start of the sentence or referring to James Watt). Now a watt [W] is a joule per second. A joule, J, is the SI unit for energy and is named after James Prescott Joule. Any SI unit that is in capitals like W or J, is a derived unit. A joule is derived from the kilogram (kg), the metre (m) and time (s). The kilogram is the odd one out in the SI system as it is the base unit, even though it is made from 1000 grams. So 1 J = 1 kg.m2.s-2 So all that is really saying is that you are moving energy with respect to time. 5 kW = 5000 J.s-1. This may seem a bit pointless, until you get to the bit about specific heat capacity of materials. Which is coming now. All materials have the capacity to store energy, so if you heat up a stone in the sun, it has absorbed some solar energy and increased in temperature. Always remember that temperature not energy. You can look up what the different amounts of energy that are needed to raise a material by 1 K or 1°C (note that it is an upper case K as it is named after a person William Thomson, better known as Lord Kelvin). It is generally better to use the kelvin scale, even though the scales match, once the offset is taken into account, 0°C is 273 K, well close enough). Now liquid water is a strange material in that it has a high density compared to its solid and gaseous states, 1000 kg.m-3 (at 277 K, 4°C). This works out nicely, and close enough for all intents and purposes at 1 kg per litre. The energy needed to increase water 1 kg, by 1 K is 4.18 kJ. This is usually written as 4.18 kJ.kg-1.K-1 or 4.18 J/kg.K. Now you have 200 litres of water at mains temperature (we shall call that 283 K or 10°C) and you want to raise it up 38 K, to 321 K So now it is just a matter of doing the arithmetic. Energy (kJ) needed = 4.18 [kJ.kg-1.K-1] x 200 [kg] x (321 [K] - 283 [K) Energy (kJ) needed = 4.18 [kJ.kg-1.K-1] x 200 [kg] x38 [K] Energy (kJ) needed = 31,768 All those letters, except the kJ cancel out to leave just the energy figure. So that is the energy required, assuming perfect energy transfer and no losses. Now remember that the power of your ASHP is 5 kW, which is 5 kJ.s-1. If you divide the energy needed, 31,768 kJ by the energy input, 5 kJ.s-1, you get left with the number of seconds. So Times (s) = 31,768 [kJ] / 5 [kJ.s-1] Time (s) = 6,353.6 Now we know that there are 60 seconds in a minute, and 60 minute in an hour. Time (minute) = 6,353.6 / 60 Time (minute) = 105.89 Now as that is below 120 minutes, or two hours, if we take away 60 minutes, the remainder is the minute part of the second hour. 105.89 - 60 = 45.89 Call it 46 minutes. Now add on the 1 hour. 1 hour 46 minutes. You will find that people often talk about their water cylinder storing some number of kWh (be careful with this one, it is as typed, not Kw/h, KW per Hour, or kill wot our). All a kWh is, is a constant amount of power, the kW part, multiplied by the time it is delivered, or consumed. That is why it is kWh, 1000 [k] x power [kW] x time [hour]. Now there are 3,600 seconds in an hour (60 minutes x 60 seconds). If we divide the kilo joules needed by 3,600 seconds, we get the kWh needed. kWh = 31,768 [kJ] / 3,600 kWh = 8.82 If you divide 8.82 [kWh] by 5 [kW] you get 1.76 hours. Which is 105.89 minutes. In reality, there are losses, and the closer the sink temperature (the water in the cylinder) and the source temperature (the water from the ASHP) get to each other, the less energy is transferred, so it will actually take longer, but that is another lecture in thermodynamics. (as usual, I may have made an error somewhere, and I am sure others will pull me up on it)

Gone west, the floor is engineered oak, thát is finished in grey wax. Close image attached. Things I would have done different 1. The walls from strip foundations to DPC, are done in cement blocks, I would do them in durisol blocks - not reliant on someone else and would have had a easier transition to the main walls. 2. Had the roof structure designed around Pozi rafters from day one. 3. We have electric towel rails, would chosen them, before the electrical contractors arrived, as two sockets ended up in the wrong place. 4. Simplified the front wall as all the corners were a real pain to build as just every block has to be cut. 5. I would get the architect to detail door and window thresholds. As this was a steep learning curve. 6. I changed the build method to Durisol block part way through the warrant process, this gave us a 4 month delay. Things I wouldn't change 1. Shopping around for materials, local building merchants are super expensive. Contractors don't really care how much they pay, as they passing the cost to you, plus a percentage. Most contractors had the material free issued from me. 2. Planning well ahead, purchasing PV, Boiler, thermal store, MVHR, at start of first lockdown in clearance sales Things I learned The house ends bigger than you think. Things take longer to do than you think. Be flexible with material and design choices

Fired in a test/ seemed poss ok/ whacked it in.. far more mortar than anticipated, but shored up the stones ok w'out foam. Mortar's a good 1.5" deep in places tho. Will need maybe two more goes to get the surfaces out enough to do final render layer. How long for this 1st fairly thick layer to set? Thanks, zoot

How to set up a failed VAT reclaim application process in one easy lesson (pay attention at the back there please .... @pocster ) In brief: make the date of Entry in the Valuation List four months before you (the Valuation Office) tell both the Local Authority and the Council Tax payer have an HMRC employee who is asking why I applied more than three months after the date I was told of the listing , and 8 months after the actual listing was made by the Valuation Office, but less than 3 months after the date that the letter telling us arrived. It took the Valution Office 5 months to tell both the LA and me of the listing Another way of saying the same thing is : disqualify the claimant from applying by not telling them about the listing for 5 months. As far as HMRC are concened, that's already two months late Facts: Date of Entry to the Valuation List (called the Effective Date of Alteration) : 1st December 2020 From that date, the clock startes ticking: you have three months from that date to get your claim in. Date which the Authority (Wyre) and I were told of the listing : after the 21st April 2021 (letter dated 21st April 2021) - I make that 5 months later To add insult to injury the HMRC are asking me to list the (planned) works carried out between 1st December and the date I applied for the refund. They already have that data: all they need to do is look at the spreadsheet submitted: each entry is dated. And all entries are listed in date order. All the employee has to do is read the words and numbers. Which makes me suspicious. Are they lining themselves up to deduct the VAT claimed for items purchased between 1st December 2020 and the date I applied for the reclaim? Can't take joke? Honestly, there's no need to submit a VAT reclaim. Nobody forces ya! Make life easier, do without the money -

So was my school, a couple of miles away. In 1976 I think it was, Concorde was doing some low altitude 'sound' test. That was nosier than the 6AM daily flight of the VC10. Still down here it it tends to be helicopters out of Culdrose, they also do training flights in jets as well. Whenever I hear a helicopter, The Rolling Stones' Paint It Black comes into my mine and I think they must be going off to devastate Goldsithney or Perranuthnoe. Penzance now has a heliport again, but they are just dropping emmets on the Isles of Scilly

It's incredibly difficult to use the appliance ratings to determine exactly how noisy an appliance is going to be when installed in your house because it depends on a number of things. First is that the frequency of the sound makes a big difference to both perception and distance of travel of the sound - e.g. low frequencies travel further than high frequencies. Second is the shape, size and general design of the room together with other background noise. There's also the actual space within which the appliance is installed which can either amplify or attenuate certain problematic frequencies. I spent a few years designing exhaust systems and silencers for motorbikes and in this area it's a bit different because you've got large pressure pulses of hot gas to deal with, but generally it's more important understand the frequency of the sound rather than just the spl as different frequencies will be perceived differently between individuals. As the only way you'll really know is when you've got it installed in a functioning kitchen and house, I'd go for the one that's most practical for your needs and then if the noise is a problem, you can deal with it through some simple acoustic measures.

Yes. You need to make it as comfortable as possible. You will be in it for years. Boxing in the underneath of a van is simple. All you are trying to do is stop air movement. So can be as simple as thick plastic sheeting or really posh insulated panels. The trouble with just a heater is that it may well raise the temperature, but you are only heating the air that is already in there. This lowers the relative humidity. Trouble is, with a caravans poor thermal insulation, as soon as the temperature drops a bit, condensation forms. It is this that causes a problem. So using a cheap A2AHP, with an adjustable vent behind it, will allow fresh air (lower absolute humidity usually) in, and heating at a much lower cost. Hot water I would just use a cylinder set to a high temp. All I had in the static I lived in 40 years ago when I was a poor student (25 quid a week including electricity at Rockley Sands Caravan Park). Mine had a tiny bath in it as well, no shower though. Was great, until the Falklands War started, then the Marine Base got really busy and noisy. I can tell you that if a helicopter, or a Harrier, flies low over a 28 foot static van, the roof bows in, and shakes the van more than any washing machine, or amorous students.

Welcome. I'm sure someone said it was very helpful to build a "skirt" (of osb maybe?) around the lower edge of the static caravan to stop the wind whistling through underneath. Helps keep things a little warmer and reduces the chance of pipes freezing.

No pipes run in the insulation. I couldn't avoid a service void in one room ceiling and external wall to get some pipes to some taps. I've got wall hung WC frames on a couple of external walls, but just put them in a false wall.

I think if you have evidence that it took 5 months to receive notice of the listing which you clearly do have then you should be ok. It’s pitiful that they can’t work some of this out themselves however! I would take the opportunity to tell them that as you don’t yet have the completion certificate and there are still a few things to finish you intend to submit a supplementary claim at a later date a la the tribunal decision in the linked case below ? Ellis and Bromley tribunal decision

I'll have a look for pictures. Cellulose was blown in through 100mm holes in the PB, which is a down-side as they all need to be but back in. Yep, wiring through the webs of the I-Joists and down the lengths of then. Very easy for penetrating the outside (airtight) sheathing and gasketting all the holes to seal.. Edited to add: Here's the only image I have of cabling into the insulated area...not much good. But some more general ones of the frame

Yes. For a 7.5mm screw, drill a 6 or 6.5mm pilot hole. I use the 70mm ones from Screwfix. An alternative could be coach screws.

We are building with 215mm concrete block and 200mm eps external insulation. It has the benefit of being quite simple to manage the glazing installation and thermal bridges. The insulation is a continuous wrap around the floor, walls and roof.

so at 26mm ID its the same bore as 28mm copper so flow rate calculators that assume 28mm copper should be valid. And the compression fittings make it do-able with a spanner. that is really excellent thank you! presume the crimp fittings need the right crimp tool (that your plumber had?), looks like they are about 100 quid, worth having if you are doing lots I guess.

I have been a long time observer on Buildhub since the idea of building a new house came about. Having read another post today it inspired to me to share our journey with some images of the build as it has progressed. Which may be of interest. From the outset I aspired to achieve a very well insulated, airtight and energy efficient house and so far its all going well. Triple glazed windows all round, u values of 0.12 all over and hopefully extremely air tight once we get further on.

Def look towards a 200mm cavity of your going for EPs beads. Wet plaster is a massive help. Then it's just the simple things. No letter box, good quality 3g Windows, every light switch and socket conduit sealed up, ceiling lights covered over using thermal hoods or clay plant pots if your tight like me, airtightness tape from the blocks to your window and door frames. There's many tiny details that aren't expensive to do but will have a big impact on your houses heat loss.

I was recommended a Shelly 1 by @PeterW and have been using it to turn my rads on upstairs. Using the app on my phone I can set it like a normal timer clock so it turns the pump on at whatever time I need during the week. You can also just load up the app and turn it on as well. Very easy to set up using wago connectors and a few wires to turn a massive amount of things on and off. The Facebook support group is also very good.

A few here have done it. Full fill insualtion and lightweight blocks for inner leaf will get you close. Or insualted plasterboard which is the common way down south for getting a traditional build to NZEB. But a 200mm cavity would make things much easier and give you more options. Have a play around with this. https://www.cba-blocks.org.uk/u-value-calculator/ Are you set on a traditional block build then? We're ICF with a total of 250mm of graphite EPS insulation (equiv to about 150mm PIR) that gets us well within passive standards. PIR is still horribly expensive so you'll want to look at blown beads, mineral wool slabs etc. For the foundations that largely depends on your ground conditions. Passive rafts from the likes of Kore in Monaghan are growing in popularity. Your architect should be well up to speed on how to get the best U values for your build. Should be...

Tekscrews?

I'll be doing that for architrave and skirting for any tiled/wood/laminate areas, but I can see the benefits of door lining going in before plastering. Maybe not before plasterboard though I guess. I'll probably loose fit when putting up the MF and slide it out for plaster boarding, before then finally fitting before plastering.

Yes, @pocster , you were asleep as usual ?. The BCO route is one way of indicating you are finished. However, there are several others as detailed below Here's the relevant bit from the form you have to complete; This is the key issue The 3 months will usually run from the date of the document you’re using as your completion evidence. Here's a photo Oh, that word 'usually' (above): needs to be read in conjunction with the notes provided in the main VAT thread.

Plenty of people post their plans for discussion. Like many I started off designating a room as a "plant room" In reality it only houses the MVHR unit and a few valves and a pump for the heating. A monoblock ASHP needs next to nothing inside and the HW cylinder was relocated to the corner of a bedroom (where one day it will be boxed in as an airing cupboard) to get it closer to the taps. The "plant room" is now better used as a workshop, that happens to have an MVHR unit in it and a few bits and pieces relating to the heating.

https://shelly.cloud Probably best to use a 1PM so you can also power monitor and understand the load.

The person who might be on thin ice here is the guy that bought half the plot and built the house. If the planners come back and enforce the original plan to be built, including incorporating the existing buildings then he will be forced to do something with buildings and land he does not own. That could get legal and messy. Your objection to any further planning permission should be along the lines that planning was granted for one dwelling incorporating the existing buildings and that has not been done. Had the original plan been built there would be no spare buildings now left to convert. It needs someone to frame that sentiment in proper planning terms.

Under the stairs then? Or with the shoes / coats?

IF you keep the cylinder in the garage you WILL need a how water return circulating system or your hot water delivery times will be stupidly long. I would put the HW tank in the house as close to the main points of use as I could so as not to need a HW circulation system.

Maybe a candidate for a hot water return pipe!

Your shout, I see nothing wrong in the cylinder in the garage if space is a premium just make sure it’s well insulated cylinder and garage space where it’s located. Along with insulated underground pipework. Best add spare ducts for future use while you are digging out!

Regardless of the heating system, heat losses and maximum heat demand will be the same. You can't fool nature. The reason that the government is pushing heat pumps is that they are the only practical way to supply thermal energy to home in a low CO2 emissions manner. This is because we are cleaning up our electricity generation. This is expensive, hugely expensive, but in the last decade we have reduced that sector emissions 5 fold. There is an alternative to use resistance heating, like we did between the 1960's and the late 1980's. This would mean we would have to add a lot more generation capacity. This is possibly cheaper, in the short term, than retrofitting heating systems. But there is a land issue. The UK does not like having wind turbines and solar farms on its land. We have convinced ourselves that only the best farming land will be used for this, will kill every bird within a mile of a turbine and the glare from a solar farm will give every child cataracts. It is all bollocks of course, but perception is more important than fact. So it is basically down to us to upgrade our homes. If your roof is suitable for PV, add it. It is cheap to self install and could probably do 70% of your DHW needs (with some diverter trickery) Airtightness and insulation really need to be considered together. External wall insulation is usually the most cost effective and will (should) improve airtightness. It is like putting a windproof winter jacket on. There will always be areas that air can bypass this that may have to be address after the installation. This may well be hard to get at area i.e. between loft space and the rooms below. These can possibly be addressed when fitting PV as scaffolding will be on site. Ideally you would convert your roof void to a warm roof system, then mechanically ventilate your house. This is expensive. So go down a layer and make the interface between room ceilings and loft space airtight, then ventilate the rest of the house. Some internal insulation may be useful. The ground floor is a large area, that is usually connected to the ground, which is cold. Insulating the floor will help a lot. This is not always easy as door and ceiling heights are important, as is the first step on the staircase. Digging up the existing floor, adding in 200mm of insulation, screen and UFH pipework is not really a viable option. But 20mm of insulation will help. Now back to ventilation. You have probably read that systems with heat recovery are not effective unless the ACH are below 3. I have never calculated this, but it intuitively make sense. So get the airtightness sorted out. It is more important than having a wall U-Value of 0.1 W.m-2.K-1. Fitting MVHR is a bit disruptive as it usually requires boxing in some pipework between floors. This does depend on the house layout. Through the wall systems are available, but they are not as efficient as proper systems, but are cheaper. Ditch any thoughts of a log burner. All these do is add CO2 to the atmosphere (what we are trying to avoid), put holes in your walls and roof (what we are trying to avoid), fill the house and street with particulates (there is new WHO guidance on this), cost a lot to run and smell. Fitting an ASHP is probably the easiest option if you have room for radiators (really convectors), but plinth heater can help in tight spaces. All these are, are fan heaters, with the heat coming from hot water, rather than an electrical element. I have no idea how noisy they are in a domestic setting, only experienced them in offices, where I never noticed them. The main thing is to not be tricked into thinking that there is some wonder technology that will sort it all out, cost less to install, have zero running costs and the government will pay for it all, and reduce your income tax to 10p. So if you hear the terms Far Infra Red, Reflective, Nano, Eco, Sustainable, Multifoil, Easy, or other such nonsense, laugh at them and walk away. Yes

Shelly can do IFTTT so just hook it in line with the boost immersion on the tank ..?

We have a 300l UVC heated by a 8.3kW ASHP, water heated to and stored at 48C, legionella cycle every 3 weeks to take it over 60C. Similar pattern of use, 2 long showers in the morning, 2 in the evening. We can comfortably run a deep bath and run one shower from the tank before it runs cool. Showers flow at 16l/m. We have never run out of hot water. Your main challenges are recovery time, i.e. how long to heat the UVC up - with an ASHP it will take longer and therefore a bigger (300l) UVC makes sense. Previous experience from a rented property with a 200l UVC was it always ran cold after two showers, and being direct electric took ages to recover. Second challenge is when you choose to heat the UVC - if you only heat during the night, e.g. E7, then ideally you'd be looking to heat all your water then and need to store enough until the next heating cycle, and therefore a bigger (400l+) UVC. Top it up through the day and you can reduce the size. And just to add another variable, are you planning solar thermal or PV?

I cannot guarantee the formula is correct but it seems to be ballpark and i’m delighted someone found it useful. You would need a 25kW combi boiler to keep up with that flow rate. A heat pump at say 8.33kW ( for easy sums) output will buy you a meaningful amount of extra hot water. It would reduce your effective draw on the stored energy in the tank by 1/3 to 8l/min giving you 30 minutes of continuous showering. If you were to space them out over a period of an hour you could have 4 x 10 minute showers, In a situation of exceptionally high demand,like with guests, you could have the tank at a higher temp or engage a couple of immersions to give you even more capacity.

Hi severnside I will try to answer your questions below 1. Start up is very low they are all inverter units and as small units biggest is 5kW when running all of them consume less than 1.5kW on a cold night so far. Pp depends on where you live here no issue but supplier should investigate all that for you if it’s needed and deal with it. 2.not turned it off since installed it’s on 24/7 at24 degrees so can’t really answer but it can kick out some heat if required so would not see it as an issue if off for awhile 3.we have gravity drained needs an external wall or a corner next to external wall pumps make a noise for about3-5seconds every 15-30mins I would find it annoying in a bedroom I think. 4. Total cost for all 4 units (these are top of the line units) inc power supplies etc etc was just under 10k from Midland Air Conditioning a very professional outfit they travel all over as well. I did get lower quotes but was lower spec kit and cheaper brands the company’s reminded me a bit of used car salesmen if you know what I mean. Also comes with 7 year warranty. service as domestic is only every 2 years as well with them (they do a lot of commercial installs eg Birmingham Bill ring etc). hope that helps

I had the 2g / 3g debate and decided on 2g as the heat loss difference was tiny. If I could wind the clock back, I would have chosen 3g. The 2g en-suite window is the only window in the house that gets any condensation. Not a lot, just a little around the edges, but for that reason wish I had spent the extra on 3g

Ignoring the acoustic advantage, personally it's getting to the stage where I think double glazed anything should be banned. The climate crisis we're all in, the carbon taxes and phasing out of fossil fuels over the next few years are all going to make a few euro saving during construction very expensive long term. That rooflight will be there for 20-30 years at least. Unless it's a protected building where space is limited or you're trying to reuse original sash frames, etc. I think a carbon tax on single or poor double glazing that don't reach a certain performance should be applied. I can understand developers looking to cut costs but homeowners should be looking more long term. End rant

And power is on. Feels like a milestone after having to elevate it to the MD of EDF!.

Installing rigid ducting is a tonne more work. I've just done my install and the sections that needed ridged ducting took a lifetime in comparison to the flexible sections. A simple vertical to horizontal bend takes a couple of hours. I cannot imaging the PITA of doing a 100% rigid install, even if it's PVC rather than galvanised steel. Walk away. I do recommend running the largest diameter to your manifolds and to have the manifolds positioned to minimise the length of the flexible ducting. I used Lindab to my ducting.

Hi update, house now built, just some cladding and slips to do outside - waiting on material. Ended up with triple glazing as suggested, made and installed by Wood Kraft in Elgin. Once the foundations were completed it took another 11 months before we were in. Spec Private water with our own borehole, mains gas, septic treatment plant. Triple glazed throughout MVHR Durisol walls, parge coated internally (sand, cement and lime mix) for airtightness, floor to wall junction with liquid airtightness paint, battons and plasterboard. External a mix of stone slips and Scottish larch. Posi rafter roof structure, battoned and counter battoned 100mm to give 350mm insulation space and then spray foam insulation. Passive House systems Reflective vapour airtightness layer, further battoned and plasterboard. Roof finished in slates and sarnafil EPDM standing seam and 3.1kw PV. Floor slab buildup, strip foundations with 100 to 150mm reinforced C34 concreted slab, 200mm of PIR insulation, UFH pipes throughout, at 300mm spacing, finished 100mm concrete with 70mm insulated perimeter. Work completed by myself Floor insulation UFH All plumbing except gas Durisol block work All battons to wall and roof Internal stud walls Parge coat Vapour control on roof internals (all ceilings match roof line) PV install, except electrical hook up Installed all bathroom s (x3) External cladding and currently doing stone slips. MVHR install Project managing and organising sub contractors who completed - ground work, roof structure, sarnafil and slates, electrical, windows, joiner for plasterboard and second fix joinery, taper for plasterboard. Images are a before and after

Hi Chris see below for answers as best I have so far 1. why switch - Brief history No gas in Village (north Shropshire) was on Anthracite boiler 2K+pa running cost. RHI came out so fitted pellet stove in place of anthracite boiler had for 7 years RHI finished in April this year. Pellets were costing me c1200pa (4 tons). Been looking at ASHPs as house is well insulated. Then we had the warm weather and house was too hot which led me to A2AHP's so we could have free cooling in summer as loads of excess PV. That really was the logic. Oh and to top it off wife has MS and so cannot fill boiler and she pointed out if I died she would have to move as cannot do the heating! using heat pump at least solves that one ? 2.Why A2A - Cooling in summer, If one unit fails still have 3 working so heat/cool still works, efficiency of the Mitsubishi units is really good and have a great installer in Midland Air Conditioning. Too many cowboys out there just wanting your cash without the skills and service to ensure a good solution. Didnt need water heating as solar thermal and PV. 3.Where - North Shropshire SY13 area not particularly warm 4.Hours a day - 24/7 its just on and set to 24 degrees on every unit 5.PV has covered all the running costs so far apart from £1.91 if we used it all 100% for heating . Reality is it is used for other things too eg car charging water heating etc but it has definitely contributed. In my figures I have assumed zero input from PV so just raw imported energy costs The AC total cost is simply total kWs used x elec rate. 6. PV array - had 3.7KW at start of fit then added further 6.3kW last year. really pleased with it. Will attach a graph showing the6 kw garage array for the last year easy as on app) overall winter is generally poor but it really depends on how many dull days we get eg dull overcast day typically 6Kw day sunny winter day c16kW day (summer 60kW/h day regularly). For me well worth outlay especially if you have an EV and or battery storage (we have both). 7. Prediction - I only have data on temps so far lowest is 5 degrees that's averaging at £1.33, 6=£1.22, 7=£1.15, 8=£1.06 will get more accurate as number of days at that temp increases 8 Heat calc - Sorry no I used my EPC to estimate heat and water loads Will post updates each month no problem Hope that helps

But if you were in a converted flat or even purpose built over 15 years old your neighbours would not thank you. Lots of people work at home. Up, shower, breakfast kettle toaster, kettle again hairdryer lunch, microwave, fridge, computer printer, TV, lighting, cooker. Face it there is no way a normal person consumes 80% of their electric between midnight and 7:00 AM. Post up your last 3 bills and it will either prove me right or prove that you are not normal.

Whew. I'm quite opinionated on this one. My *personal* view. The problems I have with Insulate Britain is that they are: 1 - Actively hurting the vulnerable in society by preventing patients getting to hospital, and impeding ambulances. And then publicly justifying it by stating - from the leadership down - that others' lives and health are a price worth paying because their cause and their opinions are so important. Here, for example, is a report of a stroke victim who was delayed for 6 hours in a traffic jam they caused, and ended up paralysed. There are multiple accounts of hospital patients being impeded. https://www.mirror.co.uk/news/uk-news/mum-paralysed-stroke-after-m25-25015653 I don't care what they say, how much they know, or how important they think they are, bastards who do that belong behind bars for a very long time, or perhaps need to be sectioned. Were IB to be attacked by men with sticks and end up in hospital themselves with broken legs or broken heads, imo it would be pure poetic justice. 2 - IB are ignorant or dishonest, conveying misinformation. They claim, and try to convince people, that "nothing is being done". Actually the large ECO3 programme has been, and is still, running throughout - doing 100s of k of energy efficienccy measures. IB are preventing people looking for insulation, rather than helping. 3 - They tend to be privileged, narcissistic hypocrites We know that ER and IB trend middle-aged middle class, and are interfering with young families, older people, carers etc. Fine, some are goons who have been groomed into criminality; others are doing it willingly. But criminals deserve criminal sanctions. One of the four who smashed the windows of the city bank lives near me. 60 year old semi-retiree millionaire who lives in an old farmhouse (energy efficient?) renting out barn conversions (not very energy efficient ones - EPC 70) for up to £2500 per week. And takes it upon herself to wreck other people's lives on the basis of a set of arguments that are not even well-informed. Overall - beneath contempt. F

If it is "Carbon neutral" then that is manipulating that phrase and kidding yourself you are reducing CO2 emissions. A Boimass boiler still sends CO2 up the flue, it still adds to greenhouse gas problems and has reduced the number of trees absorbing CO2. Just imagine of we all swapped to boimass boilers. Do you really think the CO2 problem would be solved? I don't.

Not quite. The three phase guy can’t do gas and they forgot to organise a separate gas meter install.

BillT and Ferdinand - thank you also - I shall investigate and will reply soon. I'll follow that calculation link. thanks v much! Windows open upstairs is something i need clamp down on... yes we have trickle vents in certain windows.. the double glazed patio doors are 30 yrs old and theres a single glazed door on the kitchen. You are right, we need consider those. I've told the mrs she can pay the elec and gas bill from now on, I suspect this will focus things:) NB the EPC says: "The primary energy use for this property per year is 148 kilowatt hours per square metre (kWh/m2)." is that what you wanted? ta

There is normal SCOP data out there for versions of it (AIR and GEO) - the other versions are an exhaust air heat pump only, which is essentially what @Gone West has done as I understand it with a similar system from a different brand. Since they use some of the waste heat for hot water, SCOP will vary depending on how much solar gain you have, etc. so I don't know if they can really calculate it sensibly. They have some under "Technical Data --> Planning Data" which nicely illustrates the problem - you get very high SCOPs because it isn't using the outside air as the only heat source, which is only achievable if you have significant internal gains. The cooling is linked to the MVHR system - as I understand it then it can cool the supply air to 10°C below the temperature of the return air. As it's a reversible system then it'll be broadly similar to the heating graph shown - without very high air change rates you're going to have less than 1kW of cooling. That might work in your situation (our PHPP says 600W of cooling is required for no overheating and never opening a window for ventilation), but will be heavily dependent on house design. Eventually decided against it because the hot water size is quite limiting (180 litres) and the extension tank makes for a very bulky system which doesn't fit well with our house design. Cooling is certainly possible in other ways - lots of people on here have used slab cooling very successfully (running cooled water through the underfloor heating pipes), and it's also possible to put a water-to-air heat exchanger in the MVHR supply duct to provide additional cooling.

Are you going for an air source heat pump and underfloor heating? Many here have had success with underfloor heating using an air source heat pump in cooling mode?