IanR

Assuming this is for a residential conversion, then your planning with be something like: "Change of Use from X to C3 Residential". That "Change of Use" planning permission stops the conversion from being zero rated. If you did completely remove the primary structure, you would also be in breach of the planning permission. As a Change of Use to Residential, while it's not zero rated, but rated @ 5%, that 5% is recoverable by the self-builder at the end. So it's a cash-flow issue, rather than a cost issue.

Mine was installed in 2017, but the market was even more more skewed then with RHI running which could provide double the grant the BUS scheme does. I'd noticed ASHP prices have not gone up since then (including Nibe), but perhaps everything else has.

For a 4 bed house I'd go for at least 300l, maybe 400l, even if your own need is less the next owner may have 5 occupants. It would be a shame to have to store water at over 50°C to ensure there is enough. There's improvements to be made on your energy losses (to get Certified), but I'd still pitch for a 5kW ASHP, and a buffer. I'm suggesting the larger size more for the HW side of the requirement and ensuring reasonable heat up times, although it could be argued that with your planned array size, it will be able to cover your hot water demand for most of the year, so you could rely on an immersion for the odd occasion you've depleted your HW and need to use the shower.

Are those figures from PHPP, or something provided by the installer? What's the delta T the Heat load is based upon? What DHW Cylinder size? Are you planning any PV with divert to Hot Water?

Yep, that's a bit steep, and I don't believe you get the Nibe 7 year warranty unless it's fitted by an Approved installer. Eco EastAnglia are based in Colchester - pretty sure they cover your area.

Can I ask what price you've been quoted for which model? Eco EastAnglia fitted a F2040-12, Cooling module, SMO40, MODBus module, 500l Nibe Cylinder, 200l Buffer, all copper and brass, HW recirc pump + another pump to the MVHR wet duct heater/cooler for £11.5K, which I thought was a reasonable price. First class install.

While they benefit the home owner in the march towards Net Zero, there's no direct link. For homes, Net Zero will mean using an energy source that does not create CO2, for heating and hot water. For the majority of homes that will mean electricity. Since the unit price of electricity is higher than that of Fossil Fuels, it's a benefit to the home owner if the energy losses are reduced as much as is practicable, so that a heat pumps will work as efficiently as possible to balance out the cost, or if you can reduce the energy losses enough then use an electrical resistive heating solution that avoids the capital investment of the heat pump. For a retrofit, is unlikely to be costs effective to go to the latter route and more likely the better solution is a heat pump, especially while there is the BUS grant to help with the capital investment. To get a heat pump running efficiently, you need to reduce the flow temp, ideally in the 35°C - 40°C range. To achieve this the heat emitters (UFH / radiators) need to be sized sufficiently large to meet the heat demand at that flow temp. If you can get "enough" insulation under the floor, then UFH is a very effective emitter for a heat pump powered heating system, due to the area it emits heat over. But, it's not mandatory, over-sized radiators and/or fan assisted radiators can do the job, if sized correctly. With regards reducing energy losses it's all about insulation and air tightness, and spending the budget wisely. Roof, floor and walls (including windows and doors). If you have no insulation under the concrete floor, then this really does need to come up and have insulation put down under a screed. While doing this work it is cost effective to include UFH. The roof's got to be where the most cost effective gains are to be made. 3G windows may not be necessary. Depending on the spec of your current 2G, they may be OK, but if you do need to replace them then 3G is not such a premium. For me, MVHR wouldn't be a focus, but air-tightness would. In England a house needs mechanical ventilation if the air-tightness is below 3m³/m².h @ 50 Pa. That's quite a high target, and not achieved by the vast majority of new builds. Adding MVHR above this level, increases the energy losses through ventilation, when it is not necessary. There are significant energy loss gains to be made by reducing the natural ventilation rate to sub 1m³/m².h @ 50 Pa, but the costs to achieve this in a retrofit will be high. It may be that targeting 3m³/m².h @ 50 Pa, including controllable trickle vents on windows and single room air extraction (possibly with heat recover) in wet rooms is the more cost effective option. It's worth spending some time working out where it's best to spend some money, ie. an extra 25mm of insulation under the floor, or an extra 50mm in the roof. One the forum members has created a spreadsheet to help with this.

I feel you definitely need a Planning Consultant, with Local Class Q experience, to help you with a strategy. The Refused Class Q, for Barn 1 only (and retaining the shed for use as a garage), I believe was only refused as you included the new entrance AND exceeded the permitted curtilage area on the application. Separating the permission for the entrance, and defining a curtilage not larger than the area of the barn being converted, should achieve an Approved Class Q. With regards to the new entrance, I had a quick look on Street View, and it doesn't appear that the lane is a "classified" road, ie. it's not been assigned a number such as B1234. In that case Planning is not required for a new cross-over, although Highways Agency approval is. From your OP, you are now hoping to achieve a larger conversion, than what was covered by the Refused Class Q, by incorporating the area of the lean-too and the shed. I'm not clear on whether the lean-to was part of the previous, Approved Class Q. You may be able to include the lean-to and Shed in a new Class Q, but I'm concerned by your statement: This may stop them being part of a Class Q, as they would need to be structurally capable of conversion with reasonable works. Subjective, but an avenue for refusal if the LPA wishes. However, if they were part of the original Approved Class Q, then the LPA have already accepted they are structurally capable of conversion. The other potential issue for including them in a Class Q, is whether the limit of two "large" conversions has already been met. Combing the 3 buildings into a single residential unit, pushes the conversion over the 100m² threshold, so the new residential unit would be a classed as a "large" home, of which only 2 large homes can be created within an Agricultural Unit and their cumulative area cannot exceed 450m². So, have 2 "large" homes been created under Class Q applications already, or is there room for another. If it's agreed that the lean-too and shed are structurally capable of conversion and there's room on the PD for an additional large home, then that's probably the route to go, which then provides the fall back for all the buildings to be converted to residential. If this was to get Approved I'd then start talking to the LPA about a knock-down and rebuild for the scheme you want, or failing that a Full Planning for the Change of Use that should give you more freedom for a better quality conversion, while retaining the majority of the original primary structure.

Hopefully its previous use in agriculture is a matter of fact. ie. it was part of a working Farm, and not part of the residential curtilage of the Farmhouse. A statement of fact from the Farmer would help, and if you are concerned they would add additional unhelpful info, perhaps you could draft the letter for them, "to reduce the inconvenience to them", and ask them to sign. Obviously you need a conversation with them prior to agree what they are willing to confirm. If there is any doubt that the buildings were part of a working Farm, the LPA will likely request proof of the "Agricultural Unit" (Farm number, old accounts, Accountants confirmation etc.) An "Agricultural Unit" had to once be a profitable business, able to sustain a farm worker, it's not enough to be a hobby farmer. They may also request this proof if it is not clear which Farm (Agricultural Unit) the building once formed part of. Its the Agricultural Unit that has the PD, not the buildings or the current owner, and as there is a restriction in the area that can be converted from one use to another the LPA need it to be clear which Agricultural Unit the Change of Use is being performed under. Assuming it's clearly an Agricultural building that was once part of an Agricultural Unit, the LPA should accept this (unless they wish to be awkward). It would then be for them to find evidence that it has had some other non-Agricultural Use since the Agricultural Use ceased.

Agreed, officially the barns were not last used in Agriculture, but is there evidence of this for the LPA find? ie. have they been to the site previously for prior applications where are record of their use may have been made, or is it possible neighbours would be aware of this previous non-agricultural use? So, if the barns were cleared and it as stated they were last used in Agriculture, could that be disputed? Since you over the 150m² threshold the LPA will want a flood risk assessment for a Class R. Do you know if your are in an area defined as 3a or 3b?

Insulation under the UFH? Have you considered ASHP? Off-grid fossil fuel boilers are planned to be banned for new installs from 2026. The next boiler your property has is unlikely to be LPG, and the economics of existing LPG's could well shift once all the companies currently doing new and replacement installs no longer have that business. At the moment there's a £5K BUS grant available to persuade you to go ASHP rather than LPG. Once the ban comes in there's unlikely to be grants available.

Without the planning history, it's difficult to decipher which application the planning officer is referring to. They state "refusal of the previous Class Q", but follow that with "the approved Class Q has also now expired"... Could you post the reason for Refusal, and what was different to the Approved Class Q Application. "Land-locked" is not a reason for refusing a Class Q. My own Class Q was land-locked. You'd obviously need to resolve the access prior to actioning the conversion, and that may require further planning for a cross-over to the road, but you do not need to own the land between the Class Q property and the cross-over, you "just" require a right of access over the land, which is nothing to do with planning. While I know my "Class Q's", I have to admit I only have a passing interest in Para 80's, but, this line above makes no sense. The NPPF already calls out an exception to the restraint of development in the open countryside for the re-use of existing, redundant buildings, so Para 80 is not required for Change of Use. There are no exceptions, Other than Para 80, for new builds in isolated positions, in open countryside and it is for these that Para 80 exists. But, the requirements to achieve a Para 80 are quite onerous. As well as it being an isolated site, the proposed design "must be of exceptional quality, in that it: - is truly outstanding, reflecting the highest standards in architecture, and would help to raise standards of design more generally in rural areas; and - would significantly enhance its immediate setting, and be sensitive to the defining characteristics of the local area" While there are still hurdles to jump for a standard Change of Use application (in the open Countryside), it is less onerous than a Para 80. You've posted: "SETTLEMENTS" are different to "open countryside", and have different planning rules. Do you feel the site is within a defined settlement, or is it in open countryside. I'd assumed the latter as Para 80 was being mentioned.

Hi and Welcome, I understood Para 80 to be an exception that allows for a new home in an isolated setting. I don't believe it can be used for a Change of Use. (Happy to be corrected if someone knows better) My feeling is that your option is a standard planning app for Change of Use from Agricultural to C3 Residential. That's not necessarily a restriction to Class Q, you'd only need to get an access up to the Residential Land, access across it could be handled separately, and wouldn't stop a Class Q Approval. What's more important is if the now redundant buildings were last used in Agriculture.

I feel you need to spend some money to at least get the current status recorded. If you are starting to use the land, when you haven't before, moving plant etc. and plan to build in a few years, which may involve excavation in the proximity of the wall, then you may get in a situation where you are having to prove you did not cause the collapse. If you're spending the money on an SE to do a report, then spend a little more to Engineer a repair. With a plan or works you should be able to get that costed up. It could be the start of an easier negotiation, if you've taken out the unknowns. Maybe it will cost less than they expect to resolve, or maybe you offering to contribute if they take action in the next 12 months unlocks the impasse. Either way it will certainly be in you favour if you have acted reasonably and it ends up in court. They could still do nothing.

VOIP Services can send/receive SMS messages. Don't know if all offer it though. Works with Yay.com and the others I trialled before deciding on Yay.

They don't build for current needs. They build what the legislation and lack of checks and balances permit them to, knowing they can sell everything they build due to the restricted supply.

Well done for staying the distance. Hopefully you have applied for costs (of the Appeal)

Happy with my Alu-clad Internorm windows and doors. No drafts to be felt and sub 0.1 ACH on the air test. Lot's of tricks to get car doors to seal, and the main seal into the shut-face of the door opening allows for around 10mm of compression to cover all tolerance conditions. Nearly all modern automotive (front) doors also have an additional outer lip seal to seal off the gap between door upper frame and bodyside, plus moulded rubber, multi-lipped flat seals in all the corners to handle the transitions. Front side doors are generally manufactured with an over-bend in the upper frame so that it's only once the force of the compressed seal acts on the upper area of the door that it bends out to the right shape to match the bodyside. The form of front edge of the upper door frame is always a couple of mm under-flush to the A Pillar. There's so much development work done to get automotive doors to silently seal and allow the doors to close.

BiPVco have some products that can stick directly to a standing seam roof https://bipvco.com/ They've been discussed here a few times, most recently: Alternately, there are clamps and kits from S-5 that allow for standard panels to be fixed directly to the roof, without the need for a frame: https://www.claddingmate.com/products/s5-e-standard-clamp I've not come across integrated trays for standing seam roofs as there are for slate and tiled roofs.

Could you use something like Lindab Tectherm to get through the awkward area? https://itsolution.lindab.com/lindabwebproductsdoc/pdf/documentation/ads/lindab/technical/tecflex400.pdf I used the Ø250 for some of my inlet/outlet route and works fine.

Your heating system looks fairly typical for its annual usage. As @Marvin states your COP is 4.16 (( 16777 + 8106 ) / 5985) Although I would look into your DHW usage and/or energy losses within the DHW system, as 8106 kWh appears high. Since this will generally be at a lower COP than for heating, reducing this figure will improve your overall COP, and obviously reduce your energy costs. The step up in space heating energy usage you have seen during the December cold spell, does appear excessive though. I wonder if the 7kW ASHP is only just big enough for your property's energy losses + DHW usage, such that during the cold spell the resistive heater in the ASHP was called upon to support the heating requirements. Since your SAP calc concluded a 14500kWh annual space heating requirement , but your actual use is 16777 kWh (for 50 weeks), your house is underperforming v. its design level by as much as 20%. Were any corners cut with insulation levels, or window/door performance? Did you get an air test done? For a full 52 weeks your space heating requirement will be around 17,444 kWh. For a 155m² property, that's an energy loss off 112.4 kWh/m² per year. I feel there's some room for improvement, and perhaps some easy gains to be made if you can find what area of the thermal envelope is not perfuming as designed. Bringing the property at least inline with the SAP calcs, will likely bring the ASHP sizing into line with the property performance and hopefully have it performing better in cold temperatures where resistive heating is required less (if my assumptions are correct).

I was looking for a reason for the low CoP. Since you have a short distance between inside and outside unit, the reason is not to be found here. But: Suggests you may be relying on resistive heating (the back-up heater) to support short running of the Heat Pump. Using the Back-up heater will lower your overall CoP, since it has a CoP of around 1. I assume the Boost is a short-term increase in flow temp, so ignoring that for the moment, I'd look to block the back-up heater and extend the heat pump run times (or give it longer to lift the temp from 18°C to 21°C), so that it can cover the heating and hot water requirements for the house without any resistive heating. Even if that means increasing the flow temp a little. This will provide better overall CoP. Your hot gas temp is in the correct range, so this doesn't point to any issue, and the water circuit is running at a low pressure. Fingers crossed that it's a coincidence that two heat exchangers have gone, or perhaps Daikin had a quality issue with a batch.

What's the distance between the outside and inside units? (I'm assuming you have the split version). How's the pipework between the two insulated? Are you happy that the pipes are insulated to spec? Do you know the return temp, back to the outside unit? Does the "back-up" heater come on in normal use? Can you block the back up heater and does it effect the system performance?

Hi @Furnace, a belated welcome. Once you have some success with the planning app, please come back an outline your walk from Class Q to full planning, especially as it seems you hope to site the new build in a different location to the agricultural building (if I've understood correctly). There's a few Class Q builds on the forum and a couple that have gone to full planning after securing a Class Q Approval. It's good to hear different experiences. I've now been living in a Class Q conversion of a cow shed for five and a half years, built mostly to PassivHaus principles, but without certification. I have an Advanced Foundation Technology Ltd. insulated raft, with a Touchwood Homes I-Joist frame, designed and engineered by Cullen Timber Design and insulated with blown cellulose fibre. I'm not sure if Touchwood Homes are still running, but the two brothers (Reuben & Adam) that were involved in my build are still involved with Passivhaus builds via https://mango-projects.co.uk/our-passivhaus-build-method/ and https://wilkinsonpassivhomes.co.uk/ I've not found the build method they've developed with Cullen Timber Design offered by anyone else, but can whole-heartedly recommend them. It's a very cost effective way of easily achieving Passivhaus performance levels. For window and Doors, I went with Internorm, but was very close to selecting Norsken. For cladding I went with a European Oak, featheredge cladding on the upper half, for a zero maintenance finish that tied in with an adjacent barn, and a board-on-board PAR Sapele vertical cladding on the lower half, that does require oiling every few years, on the lower half.

As @SteamyTea says, it needs to be worked out for each house unfortunately. ACH is based upon the volume within the thermal envelope and the m³/h.m²@50Pa figure is based upon the gross inner surface area of the thermal envelope, ie. floor, walls and ceiling/roof.