Updating post from Reddit.
Just spent £12,500 to replace LPG boiler in a BTL property with an air source heat pump.
Done EPC rating today, to be marked as poor for both heating and hot water.
Had to press EPC rater to get an E rating, so we can rent out. It was rated as G. So at least that moved up. BUT didn’t think heat pump would be rated as very poor.
I used to be an EPC assessor and the software and gradings are so archaic and outdated, the software generally prefers gas heating as it is cheaper per kilowatt, compared with electric. Honestly, they aren’t worth the paper they’re written on.
Exactly this and sucks they are forcing landlords to get a c without fixing it or making common sense part of the grading.
I believe there is a review of the whole epc assessment which is revisiting how the calculations are done.
What I don't like is they will more than likely favour the government pushing tech such as ground source heat pumps and render perfectly fine systems such as combi boilers as bad. How much perfect systems will be ripped out prematurely to try and hit targets. Guess we will have to wait and see.
Combi boilers are fairly bad compared to a heat pump though.
It's just what people are used to but the figures are what the figures are.
Gas boilers are cheaper to run through and thus they will be higher rated on EPC
Is that not why they are changing it to be more carbon based?
They are not.
Typical SCOP rating on a run of the mill heat pump is 3.5 so you get 3.5kW of heat per kW of electricity.
Gas is about 6p per kWh, electricity on a heat pump friendly tariff is about 12.5p.
Provided you set yourself up correctly it's about 4p per kWh of heat vs 6p for gas.
Heat pump wins easily.
You can easily see a SCoP of over 4 nowadays. 4.5 is not unrealistic.
True, but 3.5 is a safe value to show it's still cheaper even when it's cold outside
I don't believe they are.
And so is replacing it if it's brand new or got lots of life left. We need to start questioning the impact of replacing things just because something greener comes along i mean really old systems are a no brainer but the environmental impact of replacing things. Most parts are sourced from china and just put together in england. We are literally shipping crap across the world just to say oh wow i have the latest green tech. When we rip out old systems where do you think it goes? Back across the globe to either indian open air dumps where kids sort through it for anything of value or it ends up in china to be reused. Just seems like we could be doing a lot more for the environment by putting some common sense into this epc made up crap.
Engineers can work out the pay back period.
This is normal stuff for them.
Need to define terms- in many contexts combi boilers are a very effective solution compared to heat pumps. The two common German condensing combi's are A rated (over 90% efficient).
Space heater is 100% efficient, heat pumps are multiple 100's% efficient.
If efficiency is the only metric then gas boilers are about the least efficient method for heating available.
I quite agree that electricity is 100% efficient, heat pumps CoP in the summer many times that. Take a step back though and the problems with heat pumps begin to emerge. Their winter efficiency drops until their CoP is barely better than just running a bar fire; below freezing they are a liability. In cold and wet Scotland, we are seeing defrosting cycles running multiple times a day, which requires heating. Not very efficient.
Beyond efficiency, they are sometimes proving ineffective. Homes need to be very well insulated to benefit from the lower heat produced, preferably airtight with Heat Recovery systems. So not cheap to retrofit in existing housing stock. Often done badly, there are numerous tales of systems simply not being able to perform.
The other issue is that electricity costs are traditionally multiples of gas and guess where half our electricity comes from? Power Stations run on gas. So the overall efficiency of heating a home with power which began life as gas, burnt to produce heat, converted into electricity, sent down the line (with transmission losses) then arriving at the heat pump to be transformed back into heat is?
It definitely has to be tailored to the property, but heat pumps are amazing when appropriate, by far the most efficient method of heating, even if the local power station is gas.
Ground source solves a lot of the problems with colder temperatures, and obviously different units will be designed for different use-cases, definitely shouldn't be discounted though.
Absolutely agree with most of that. Holisticly approached, with near Passiv detailing, ground source heat pumps are absolutely magic. MHRV drawing from below ground are also superb performers.
The issue is imposing ASHP on inappropriate houses, where there are big bills to upspec. radiators etc and then customers are finding their running costs are dearer than the old gas system. I am a house-builder in Scotland, so these things aren't theoretical...
Winter efficiency is not close to a bar fire.
I've had no direct experience of ASHP since Covid, so perhaps CoP has improved (or are you saying worse?!) but we need to define our terms. I'm talking about a wet Scottish winter as problematic for these machines, around the freezing mark, when warm water is being pumped outside the house to defrost the heat exchanger plates. These cycles can prevent achieving room temperatures and we've seen them running multiple times a day, particularly with outside temps near 0⁰ to only a few degrees below. Air's ability to hold moisture reduces much below this point...
Modern heat pumps can handle UK winters without issue - they are commonly used in Scandinavia and Canada - and they can hit yearly average efficiencies of over 400%. Peak efficiencies are much higher than that.
You might need larger radiators in a retrofit, depending on the property.
I am a Scottish builder, so I'm speaking of what I have experienced and what the heating engineers are discovering. It's daft to lump all of the UK into the same climate. Scandinavia and Canada have much colder winter temps, which means drier air, so the exchange plates don't frost up. If radiators running at 40⁰ can keep homes warm in sub zero temps, then your spec. must be heading towards Enerphit standard?
90% versus 200-300% when averaged across a year.
Gas boilers are not very efficient compared to newer technology.
Closer to 400% averaged over the year.
But ASHP is also pushed by the government and hasn't helped here.
Is it as stupid as literally assuming "well, it's electric innit" and then marks it down as "electric heat" with a fancy label instead of bothering to account for things like the COP?
Heat pump efficiency calculations are actually based on a seasonal performance factor of the heat pump at specific plant size ratios based on the design heat loss of the property. The calculations are around 90 lines of code
So, how did OP's assessor manage to rate it as "poor"?
Poor means that the cost rating of the heating is between 7.41 and 10.66 p/kWh, from a unit price of 13.19 p/kWh divided by the efficiency of the system, then multiplied by (1 + 0.29*(1.0 – responsiveness))
So overall, it's just a reflection of the raw cheapness of gas and - despite the calculations going into it - basically nothing else can ever rate so highly?
I feel like "cost" and "efficiency/environment" aren't two things that can be expressed well on an EPC chart.
You know it says "the better the rating and score, the lower your energy bills are likely to be" right under the rating diagram, right?
My record rating is around 15k
It's not like we don't know this. But rules is rules.
The assumed none is killing the rating, the flat roof should have insulation they are just assuming none. Same for the slab.
You could improve the rating by opening up a small section of the plasterboard to prove it. If it doesn’t then you will know and can add some.
Long term the G rating won’t cut it. You are also likely to put off some renters as it would be super expensive to heat.
If it doesn’t then just add a big square of it where you opened up a hole, checkmate.
Found the real landlord!
😜🤣🤣
I got 500mm loft insulation.....around the hatch
Not exactly unknown on newbuilds either
Do you paint your hinges? 😂👏
r/Angryupvote
Work in an architects and did a semi-d block of flats and due to being finished at slightly different times were rated under slightly different regimes so same spec, heating etc but different ratings.
The idea behind them is good but as per usual with government stuff it's implemented in a way that isn't really fit for purpose.
Most renters you mean. It's the first thing to look up.
How did you not know what the outcome would be from the installer ahead of time?
EPCs are for the cost to run a home, not the carbon emitted.
Solar gets you a higher EPC per pound spent.
Cos the guy did the property for us before , when it was rated G. Had to get exemption while tenant was in property.
You would have qualified for exemption after spending over £10k. Might have been a better option than getting it to an E
It looks like the surveyor has entered the main heating source incorrectly. Ask him to check his heating code and the secondary heating. The EPC is wrong not the score from an ASHP
Fwiw it seems it will be EPC C by 2030 if you can get information about insulation
I'm looking to decarbonise the hell out of my house
https://www.elmhurstenergy.co.uk/blog/2024/10/01/epc-reform-consultation-expected-this-winter/
New update coming next year. Should account for heat pumps more. And room in roofs
Roof rooms are far more complicated, and heat pumps will have the same outcomes as the unit prices used to calculate the rating haven't changed
I know but don’t want to wait that long to rent out. Only cost £50 for EPC rating and needed E or higher to rent out
Just forge it.
Worst advice here, crime 😂
Wonder why landlords gets a bad rep 😂
Send the assessor a copy of your MCS certificate for the ASHP install as if they can select the exact model and design flow temperature in the EPC software it will improve the score. Also be sure to confirm if it is configured for weather compensation (and send photos showing this) as this may again bump it up.
If you just add generic ASHP the rating is always cr@p if you select the specific unit and if it has weather compensation or not you can make some improvements.
You could look to solar or to WWHR to make further improvements (WWHR gives a good improvement and while has some capital costs is no maintenance and lasts for decades).
This should be the top comment - see this all the time in ASHP groups, just putting “heat plump” will tank the EPC, but putting in the specific model will improve it. Please ask your assessor to fix it and report back OP! /u/netzero1967
Yep EPC is a measure of efficiency (cost) so gas boilers are better for your EPC than Heat pumps but worse for the environment.
Which for a homeowner seems the correct way to measure efficiency.
Im sure the heat pump will get a better rating in time to come. On this relentless march to energy efficiency the minimum rating to rent will only get higher.
Which is a good thing
Absolutely right.
We have a heat pump and it's fantastic. Really warm and low energy usage.
However we got our EPC redone, and like yours it comes out badly because of the assessment software they use. EPC assessment needs an overhaul.
Was there a recommendation on your EPC to put a heat pump in?
No. We did it anyway
Well then you can't really complain that it impacted your rating
Going for the best option over gaming an archiac rating system isn't a bad move.
Definitely should be complaining, it needs updating.
Let me know when they complain
>However we got our EPC redone, and like yours it comes out badly because of the assessment software they use.
That’s not a complaint, that’s an observation of what happened.
They are reviewing the way that the EPC is calculated and I'd imagine during this government they'll make changes to positively impact EPCs with Air Source Heat Pumps.
Working for a house builder, and as someone that engineers a lot of retrofit and regeneration projects, this is a problem I know very well. I will underline that this is a stupid problem to exist, and one which is easily solvable if the government can pull their finger out and properly listen to a consultation response.
Essentially the calculations are out of date.
SAP ratings are used to measure building energy efficiency in respect to the CO2 emissions of the building. This is the mode of compliance under Part L of the Building Regulations and crucially was updated in 2021 to account for how much greener the national grid has become per kWh of electricity produced. I am grossly oversimplifying but when considering heating systems, any properties that opt for electric heating opposed to gas, LPG, oil, coal etc will have lower CO2 emissions and therefore the building will have a better SAP rating. SAP is generally only used for new build and conversion properties as a tool to meet the Building Regulations, it is not intended for consumers. Most existing stock on the market are not required to meet these requirements. For consumers, however, all this means is that the better insulated and more efficient your home is, the better it scores on its SAP.
EPC ratings also represent a given buildings energy efficiency but crucially is a measure of how much it costs to run the building – it takes no regard of CO2 production like SAP. EPCs are the primary mode of evaluating building performance for the purpose of informing consumers at sale and rental of residential property. EPCs apply to every single home in the UK market, both old and new and as you have discovered, the EPC system prevents poor performing homes from being let on the market. Unfortunately, the calculation method for EPC is the direct inverse to SAP in that electric heating is the most expensive form of heating, so you get penalised for installing it.
The government (previously under Sunak and now again, recently, under Kier) are looking at introducing mandatory energy efficiency (MEES) targets for residential buildings. This will mandate that all rental properties achieve an EPC C rating in order to be eligible to rented out by a landlord. This is to try and modernise the UK building stock and make it more energy efficient. Unfortunately, as outlined above, the EPC methodology only concerns running costs, not CO2. There are currently no discussion that consider the vast disparity between gas and electric prices, and currently anyone who has taken an initiative to migrate from burning fuel appliances to electric (i.e.. replacing gas boiler with a heat pump) will find themselves on the wrong side of the law come 2030.
So long story short, the government needs to amend how EPC works to take account of CO2 emissions and rebase this against the cost per kWh. Only then will the system work as its intended.
I think you're confusing the new build compliance metrics with what's actually on an EPC. SAP and RdSAP both produce an EER, EIR, tonnes of carbon, carbon per square metre, and primary energy. Only the EER is cost-based and the primary output metric shown on the EPC. If you look at a SAP XML, you'll see them all.
No I’m specifically cherry picking the bits that are relevant to consumers. I’ve worked with SAP for 13 years. Previously under SAP 2012 any inclusion of electric heating practically destroyed the results as they were based on 2012 statistics for co2/kWh. That’s why you saw everyone slapping solar PV on almost everything to achieve the DER rating as it had a huge offset advantage. Under the new SAP 10 (2021) this no longer works as the grid has significantly decarbonised and each kWh of electricity produces significantly less CO2 than it did in 2012. It now makes more sense to specify electric heating systems that are more efficient than gas because of the CO2 offset. The government are incentivising a move from burning fossil fuels in all parts of the sector, and SAP 10 makes it very difficult to comply otherwise.
What hasn’t changed to reflect the new SAP 10 is RdSAP. This still works under 2012 figures meaning electric heating gets penalised in EPCs issued for consumers. It is due for an update next year, but I’m not clear whether the cost metric that is the current difficulty will be fixed.
The unit prices for electricity are 25% higher in SAP 10 to SAP 2012, which means you'll get a better EPC rating under SAP 2012 than you will SAP 10. Table 15 in the SAP 10 specification shows that a SAP 2012 C80 would be a SAP 10 D67.
RdSAP 10 will continue to use the 2012 unit prices until RdSAP is replaced by the EPC and existing building wrappers for HEM
Just sell it
You probably could have gotten this for free with the ECO4 scheme. My company specialise in this...
What is eco4? I did get 7,500 grant for heat pump
ECO4 is 100% funded solar panels, heating upgrades and insulation. only certain households qualify
I very much doubt landlords will qualify for this
Honestly you would be surprised
At least you're living under a VERY GOOD roof.
Poor means that the cost rating of the heating is between 7.41 and 10.66 p/kWh, from a unit price of 13.19 p/kWh divided by the efficiency of the system, then multiplied by (1 + 0.29*(1.0 – responsiveness))
This does not surprise me. EPC calculation is just plain weird. I need to replace a dual flue gas boiler and have been told that putting an electric one in will be bad for my EPC rating as it uses more energy than a gas one.
When the requirement moves to “C” I don’t think it will be possible to rent out the property without shelling out a shed load of money.
I get that the environment is important but a poor EPC rating should demand a lower rent and market forces will dictate what happens next for either the owner or tenant.
The rating system is pretty intuitive for 95% of cases. The rating displayed is cost-based because of a correlation between heating costs and heat loss. If your dwelling is expensive to heat, it's more than likely due to losing heat and needing to run the heating more. When you have highly efficient heating systems which are also expensive to run, you begin to see that relationship breaking down, unless the COP of the heating system is at least 3.5, to overcome the cost differences.
What landlords tend to overlook is that any policy decision to meeting a particular rating in the future will not be based on the current calculation methodology. The Scottish government have already completed a consultation into EPC reform, displaying multiple performance indicators on the EPC rather than the single top-line rating which we have now. Energy policy is nuanced and so a single rating cannot cover all of the scenarios. You want to address energy poverty, you use a cost-based metric; you want to demonstrate reducing emissions, you used a carbon-based metric; you want dwellings to be efficient, you used an energy or fabric efficiency metric.
Right now it feels like landlords are being asked to hit a moving target by pinning a specific “energy rating” to whether a property can be rented out or not. Ironically this target does not apply to owner occupiers.
So I go back to my previous point, let market forces dictate rental levels. A poor EPC rating means higher energy bills and hence should demand less rent. At some point the landlord would need to either sell up or upgrade (to warrant getting more rent). But why place this requirement on rental property and not owner occupied - that’s the real question!
It will be. Scotland consulted on this years ago with the aim of introducing it. If the UK government followed a similar thread, it would require a minimum rating to be met either on sale or following major works to the property -- so if you were adding an extension or something, you'd need to ensure the property as a whole met a standard. The works criterion kicked in if the works were more than 10k.
Had my epic done for a self build (we won't ever be selling so the score isn't important), I think we got a D but were told if we paid for some extra tests it'd probably be higher.
Any landlords in London ?
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There's a nationally-recognised database of products, formerly called SEDBUK, and includes product efficiencies for boilers, heat pumps, mechanical ventilation systems, and heat recovery systems. Manufacturers have to submit independent EN14825 testing data for every single variant of their product to be included in the database.
The efficiency of a heat pump is determined by the design heat loss of the dwelling and plant size ratio of the device at specific seasonal performance factors. You can't just grab a number off the side of the device and plug it in.
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Because the same default is applied to all dwellings in the same scenario. It means there's consistency in the methodology
Existing properties in the UK (non New Builds) arent really set up to properly utilize Air Source Heat Pumps.
They tend to cost the unknowing home owner more money than they save and definitely aren't considered energy efficient.
In my opinion its one of the greatest cons and scandals the UK has faced and on par if not worse than the Post Office Horizon scandal.
Home Owners need educating but then it doesnt benefit the unscrupulous plumbers fitting them to get the government kickbacks wont bother as its not in their interest to do so. (hence why its a con)
DONT buy a heat-pump unless you're home is a new build and specifically constructed for "envelope airtightness" because your bills will be thousands more per year, not lower and you wont be able to afford to use them to heat your home.
Heat pumps really don't work energy efficiently in the UK for any properties built pre-1960 and/or bigger than 70 sqm. It's a real blunder for UK Govt to keep pushing for them when performance is so property dependent.
Lol
I’d spend 12.5k on the other items so no need for the green bling.
Heat pumps are dreadful!
mine cost £12,500. although after govt grant i have paid £5,000. that includes a full re-pipe, all new radiators.
it sound noisy, i feel sorry for the neighbours lol
It shouldn't be noisy, and unless you have bloody long radiators (like 9ft+) underfloor is the goto for heat pump.
Radiators really make the unit work hard (probably why it's noisy).
We had issues with ours as it cost a fortune, was noisy and house was always cold. We moved in with it already installed and complained about it to the HA until the actual installer had a look and replaced the entire unit (warranty issue) and fitted anti vibration blocks and connected the underfloor heating ( it had both underfloor pipes and radiators, installer assumed when they replaced the boiler they hooked it back up to the radiators instead of the underfloor) radiators got removed and the house became toasty, quiet and very cheap to run.
Kinda miss it now we have moved again and back on a combi boiler especially as the savings would of doubled up with the electric car tariff being insanely low.
But anyway , the installer couldn't stress enough how radiators are just shite for air source, even the huge ones.
They are noisy and they don’t efficiently heat a property, despite all the governments preaching. Feel sorry for both tenants and neighbours!
If you ignore that they produce 3 to 4 times the output of heat to energy they consume I suppose so
The efficiency of heat pumps, aka a big reverse refrigerator with the coldside outside and the hotside inside is largely overstated. In order to boil and condense the refrigerant the compressor motor has to work Very Very Hard to force it through the low and high pressure system. It’s not a wire on fire like a resistive heater, but it’s still a lot of work.
The ubuiquity of the term ‘heat pump’ is one of the most successful ever rebrands of technology invented in 1911 ever made.
It absolutely is efficient, and should be relatively noise free if good quality and installed correctly.
No motor nor air wafting fan on earth is silent mate. You need your ears tested.
Relatively noise free does not mean silent
A modern compressor is 45 to 50dB. While not silent, it is not a major hassle.
Let's book him in at the same time we book your comprehension test
My boiler makes noise when it's on.
As our installer stated , if the house/budget can't choose underfloor heating air source is not a viable option at all. After experiencing both the radiator and underfloor in the same property I would have to agree with him.
It can work without underfloor if the radiators are big enough. Underfloor heating is the best setup as it has the most surface area which means low flow temperature. The lower the flow temperature is the more efficient the unit runs.
Yeah but most affordable new build houses cannot/do not fit the ideal size needed in most of the rooms , typically only living rooms, dining rooms and often master bedrooms. Obviously older houses have much bigger rooms but they come with their own issues.
This cannot fit/do not fit is giving heat pumps a bad name as they are having to work harder for less results costing more to run and being loud to boot.
If you're going to install a heat pump, you should advise the ideal set up not the half job that costs more to run.
I agree with you.
Unless the home is well insulated, it's really hard to fit radiators that will work well with heat pump. If I was to install a heat pump I wouldn't go without underfloor heating (unless if it's for a small room that doesn't need much heating).
Don't get me started of new builds with inadequate heating systems. I've seen some with electric heaters. Some developers have no shame.
Mine is fantastic
>Heat pumps are dreadful!
Nope, they're actually really fucking good.
Sounds like you don't understand what an EPC is...
How is it possible this is a surprise to you?
If you can't grasp something this basic you're probably in the wrong game maybe put your money into an index fund instead.
Money saving expert has some great tips for someone new to investing!
Please Keep it Civil
That's because air source heat pumps are useless on a building scale smaller than a warehouse. They have to be supplemented by a heater in cold weather. Dead end technology, always has been Ground source heat pump is slightly better and scalable.
Associate Director in a land agency/renewables/BNG field
>That's because air source heat pumps are useless on a building scale smaller than a warehouse.
Talking out your arse and scientifically illiterate, great combination.
BS, BP or Shell employee?
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They mean the ASHP itself needs to run a heater in certain low temperature situations to continue operating, not that your home needs extra heaters within it.
A defrost cycle on the air source heat pump is not the same as using supplemental electric heating in the winter.
Someone doesn't know what they're on about.
Associate Director of the not knowing what you're on about department?
>Associate Director in a land agency/renewables/BNG field
So you're not an engineer. Heat pumps get COPs of 4-5+ if installed correctly
Heat pumps are shit. Some woke bollocks to get make people poorer. Very much like electric cars. Stop following the crowd and use your head. The majority of people who have installed them have regrets
They have regrets because they got a shit installer that sold them a solution that's not adequate for their home.
Heat pumps work really well with underfloor heating (otherwise you need big radiators as the system need to work with a low flow temperature) and a somewhat well insulated home. There's no magic to it.
'majority'. I'm absolutely sure that is not true. The main issue with heat pumps is cowboys doing poor installation, the other issue is to do with the price of electricity being artificially pegged to the price of gas.
EPC and ESG is a scam. ASHP waste of money and not efficient.
>ASHP waste of money and not efficient.
They often get SCOPs between 300-400%, how is that not efficient you wassock.
Energy efficient they are.
Cost efficient they aren't.
Gas is so much cheaper than electricity currently that even with high COPs, it's likely still cheaper to have gas.
>Gas is so much cheaper than electricity
Yeah, about three to four times cheaper. So ASHP can often end up being a bit cheaper to run if you get a good install, particularly if you have a tariff that makes it cheaper to reheat the tank overnight.
This post + operating costs prove that they are inefficient. In a climate where its cold outside most of the time, they arent going to be working very well at all.
They are absolutely not a suitable replacement for a modern gas boiler.
GROUND source heat pumps on the other hand are fantastic and make sense.
Now talking on EPC specifically, as per all the other comments on this thread - the standard is not fit for purpose and the inspector can ruin your rating just because of the assumptions they make during the inspection - that is insane and could make a property effectively unsaleable. DUMB.
>In a climate where its cold outside most of the time, they arent going to be working very well at all.
They're used all the time in Norway.
OH so theres a WORSE use case out there? that means they must be GREAT.
TCO including running costs and the requirement for alternative energy/heat sources on the EPC survey render them an expensive mess. If you have the luxury of solar/free electricity its a different game but given we are talking about rentals, i dont ever see the equation balancing.
>OH so theres a WORSE use case out there? that means they must be GREAT.
Wtf are you talking about?
The point was that SCOP can remain pretty high even when very cold outside which, in the UK, is very rare (it doesn't often go below -10). People who think heatpumps don't work when it's cold simply don't understand how they work or what efficiencies modern ones can achieve.
Also, running/installation costs aside, there's value to burning less fossil fuels you know...
>Also, running/installation costs aside, there's value to burning less fossil fuels you know...
There are just too many variables to make them work in a cost sensitive environment.
The horror stories of people paying £1000's in electricity to heat their homes due to the rise in rates etc etc.
Until the grid is 100% nuclear + renewables ill stick with gas and enjoy burning cheap fossil fuels.