Home  5  Books  5  GBEzine  5  News  5  HelpDesk  5  Register  5  GreenBuilding.co.uk
Not signed in (Sign In)

Categories



Green Building Bible, Fourth Edition
Green Building Bible, fourth edition (both books)
These two books are the perfect starting place to help you get to grips with one of the most vitally important aspects of our society - our homes and living environment.

PLEASE NOTE: A download link for Volume 1 will be sent to you by email and Volume 2 will be sent to you by post as a book.

Buy individually or both books together. Delivery is free!


powered by Surfing Waves




Vanilla 1.0.3 is a product of Lussumo. More Information: Documentation, Community Support.

Welcome to new Forum Visitors
Join the forum now and benefit from discussions with thousands of other green building fans and discounts on Green Building Press publications: Apply now.




    •  
      CommentAuthorfostertom
    • CommentTimeFeb 19th 2022 edited
     
    Not a bad article but doesn't really bring the benefits to life:
    https://www.theguardian.com/money/2022/feb/19/passivhaus-how-to-insulate-your-home-against-soaring-heating-bills

    "... based on anecdotal evidence ... expect a Passivhaus to sell for between 5% and 10% more than a similar property built to normal energy efficiency standards.
    Because of the desirability of these homes, ... be wary of unclear marketing claims. “A lot of people will say a house has ‘Passivhaus principles’, which actually has no meaning really.” A true Passivhaus will always have a certificate to prove its status"

    A lot of people satisfy themselves that they've built to full PH standard, but don't fork out for the certificatiojn procedure. That's begining to look like a poor economy, to eventually recoup an ever-increasing resale premium.
    • CommentAuthorJeff B
    • CommentTimeFeb 19th 2022
     
    Very interesting article. I guess this is all down to the sudden massive increase in fuel prices. I wonder if folk will also start to take a bit more notice of EPC ratings (yes, I am aware of the various opinions on these!) as I suspect until recently prospective house buyers are more interested in the style of kitchen units or the size of the patio. Will we see A or B rated houses also attracting a better resale value?

    It seems crazy that it only costs 5% to 10% more to build a PH house compared to a "normal" property and yet how few of the former there are. If only I had my time over......:wink:
    •  
      CommentAuthordjh
    • CommentTimeFeb 19th 2022
     
    Posted By: Jeff BVery interesting article.
    It's good to see some coverage and especially of the value of certification. They're wrong to say you get a plaque in the price though; that's an add-on you pay for (I think we paid Ă‚ÂŁ90).

    But passivhaus still needs a whole lot more publicity and attention from government. This country is way behind others. We had a couple of articles on our local news programme recently about passivhaus in the area; I posted a quick link on nextdoor and only got one response, which was 'what is passivhaus then?' :sad:

    Introducing regs to allow PH as an alternative to building regs Part L & F would be a good start, as would allowing local authorities to mandate PH for buildings in their area.
    • CommentAuthorMike1
    • CommentTimeFeb 20th 2022
     
    Posted By: fostertom"... based on anecdotal evidence ... expect a Passivhaus to sell for between 5% and 10% more than a similar property built to normal energy efficiency standards.

    I'd expect something similar; houses from the 1980s Energy World demonstration project in Milton Keynes were selling 3% above market rates 20 years later (see https://publications.parliament.uk/pa/cm200405/cmselect/cmenvaud/135/135ii.pdf) and, although well ahead of energy standards at the time, PH is obviously much better.
    • CommentAuthorJonti
    • CommentTimeFeb 20th 2022
     
    Posted By: Jeff B
    It seems crazy that it only costs 5% to 10% more to build a PH house compared to a "normal" property and yet how few of the former there are. If only I had my time over......http:///newforum/extensions/Vanillacons/smilies/standard/wink.gif" alt=":wink:" title=":wink:" >


    The biggest barrier to PH builds on a mass scale is we simply do not have the numbers of skilled workforce nor enough tradesmen with the attention to detail nor the required oversight of building quality nor enough construction companies who have quality of build as an important factor.
  1.  
    We recently sold a house, rented a house and then.bought a house. The energy ratings of the 3 houses made no difference at all to the prices or the rent.

    That was painful because we had spent an awful lot of money on transforming the energy efficiency of the first house, expecting it to be our 'forever home', and we basically lost all of that money when we unexpectedly had to relocate. We are being a lot more level headed about improving the next house.
    .
    For most houses, the energy costs each year are only a small % of the cost of capital (eg mortgage repayments or rent) and so slashing the energy bills could add only a smallish % to the affordability and hence price, even if people were aware of them.

    None of them were PH so I don't know if they genuinely have a price premium, maybe there is a specific market of enthusiasts who will pay extra Ă‚ÂŁk for those.
    • CommentAuthorrevor
    • CommentTimeFeb 20th 2022
     
    Posted By: JontiThe biggest barrier to PH builds on a mass scale is we simply do not have the numbers of skilled workforce nor enough tradesmen with the attention to detail nor the required oversight of building quality nor enough construction companies who have quality of build as an important factor.


    I totally agree. DT had article today about Heat Pumps and wood burning stoves that appeared on my smart phone. In the comments a householder of a brand new 4 bed house jumped to the defence of HP saying how good his was but when the temperature outside was 0-3 degrees he was using 60 KwH of electricity per day and at 3 to 10 deg 30Kwh I got the impression that was OK!! but added the rider he would not have one in old house so maybe it was deemed to be and expensive way to heat the house. Probably built to building regs standards and not very well at that.
    • CommentAuthorJeff B
    • CommentTimeFeb 20th 2022
     
    Posted By: WillInAberdeenWe recently sold a house, rented a house and then.bought a house. The energy ratings of the 3 houses made no difference at all to the prices or the rent.

    That was painful because we had spent an awful lot of money on transforming the energy efficiency of the first house, expecting it to be our 'forever home', and we basically lost all of that money when we unexpectedly had to relocate. We are being a lot more level headed about improving the next house..


    That was my fear with our house. I have spent a great deal of time and money on draught-proofing and insulating the place and have reduced the space heating requirement by half. I can no longer say that this will be our "forever house" as I can see that in the not-to-distant future we may have to downsize as the place is too big for the two of us. Maybe with such a lot of attention being paid to energy prices this could alter people's thinking when they look at properties to buy in the future and the EPC may take on a greater significance in the thought process.
    • CommentAuthorJeff B
    • CommentTimeFeb 20th 2022 edited
     
    Posted By: revor
    Posted By: JontiThe biggest barrier to PH builds on a mass scale is we simply do not have the numbers of skilled workforce nor enough tradesmen with the attention to detail nor the required oversight of building quality nor enough construction companies who have quality of build as an important factor.


    I totally agree. DT had article today about Heat Pumps and wood burning stoves that appeared on my smart phone. In the comments a householder of a brand new 4 bed house jumped to the defence of HP saying how good his was but when the temperature outside was 0-3 degrees he was using 60 KwH of electricity per day and at 3 to 10 deg 30Kwh I got the impression that was OK!! but added the rider he would not have one in old house so maybe it was deemed to be and expensive way to heat the house. Probably built to building regs standards and not very well at that.


    Was this the article you refer to...

    https://www.telegraph.co.uk/money/consumer-affairs/swapping-useless-heat-pump-log-burner/

    I cannot open the article but the headline sounds intriguing!
    • CommentAuthorrevor
    • CommentTimeFeb 20th 2022
     
    Yes that is the one. Just opened it on my PC. My wife has a digital subscription to the DT so that is why I get in on my smart phone but it does not explain why can open article on my pc. Actually the article does not mention swapping HP for WBS journalistic licence I guess.
    •  
      CommentAuthordjh
    • CommentTimeFeb 20th 2022 edited
     
    Posted By: revor
    Posted By: JontiThe biggest barrier to PH builds on a mass scale is we simply do not have the numbers of skilled workforce nor enough tradesmen with the attention to detail nor the required oversight of building quality nor enough construction companies who have quality of build as an important factor.

    I totally agree. DT had article today about Heat Pumps and wood burning stoves that appeared on my smart phone. In the comments a householder of a brand new 4 bed house jumped to the defence of HP saying how good his was but when the temperature outside was 0-3 degrees he was using 60 KwH of electricity per day

    I agree that we're not equipped yet to build PH on a mass scale, but the way to do that is to build a lot more than we are doing so we can expand the number of people with some training! None of the tradespeople on our project had any experience of building a PH, but we managed to motivate them to do so and now they all do have that experience.

    The article doesn't say how big the house was nor how hot they heat it so it's difficult to make any statements, but for comparison we're using 4 kWh each night to heat our house for the day with a simple resistance heater at the moment. I suppose a 10-year old heat pump won't be as efficient as a modern one but 60 kWh sounds extreme.

    FWIW I can open the article on my PC as well. Can't see the comments, but that probably requires me to enable JS.
  2.  
    We designed and built our own house to PH standards and sold it nearly a year ago. We had lived in it for three years. It was heated by an electric towel rail in each of the three bathrooms and supplimented by an EASHP in the MVHR system. The EPC was A95. We had no trouble selling it and in the end had three people trying to outbid each other. All the buyers were interested in buying it because it was a low energy house but whether we achieved a higher price than a standard house is impossible to say because it was in a small hamlet with no other similar houses in the area. From my experience I would say a low energy house is easier to sell but I'm unsure whether there is a premium to be paid for one.
    • CommentAuthorDarylP
    • CommentTimeMar 4th 2022 edited
     
    sort of connected to the above... I had two calls yesterday from people who are re-considering their proposed purchases of houses, due to the G-rated EPCs, asking how much improvements / upgrades would cost...?
    • CommentAuthorowlman
    • CommentTimeMar 4th 2022
     
    How long does PH certification last without being re-assessed ? People outgrow, ( or out-love ), their homes, and with each client change the risk increases for modifications to occur.
    I've seen massive changes in relatively new properties I've been involved with. I've seen Ă‚ÂŁ10s of thousands of beautiful internal fittings chucked in a skip, in what were fine high build standard homes, (not PH), only to be replaced with some other "stuff" more to the new occupants liking. People are fickle and they WILL change things. The original owners design ideas won't be set in stone with a new occupant.
    •  
      CommentAuthordjh
    • CommentTimeMar 4th 2022
     
    Posted By: owlmanHow long does PH certification last without being re-assessed ?
    I don't think there's any such notion. We had a bit of a discussion about it a while ago. I agree there should be some such notion but I'm not sure how it would work. PH doesn't care all that much about what is inside the house except for the basic services. Presumably the certificate becomes invalid as soon as anything listed in the PHPP is no longer there.
    • CommentAuthorowlman
    • CommentTimeMar 4th 2022
     
    It's not so much fixtures and fittings although some could have a detrimental effect. What about re-arranging the internal walls for example,- not uncommon. There is also the possibility of knocking holes in external walls. New clients may not be fully briefed as to the effect such measures may have.
    • CommentAuthorJonti
    • CommentTimeMar 4th 2022
     
    My understanding is PH certification is for 'as built' not that it something that needs reassessing which is over thinking it in my opinion.
    • CommentAuthorowlman
    • CommentTimeMar 4th 2022
     
    With no ongoing certainty of the house performance therefore, using PH as a selling point perhaps should carry a health warning; a case of caveat emptor.
  3.  
    Same as with EPCs, the difficulty is to recertify the energy performance if the present owner doesn't have evidence of all the construction materials and details. If the surveyor cannot see what insulation is under the floor or in the walls, or see certificates for the windows and appliances, they have to assume the worst.

    The resulting certificate may be disappointingly poor, which (it is intended) would have financial consequences.
    •  
      CommentAuthordjh
    • CommentTimeMar 4th 2022
     
    Posted By: owlmanWhat about re-arranging the internal walls for example,- not uncommon.
    How would that affect a PH certificate? It simply doesn't care.

    There is also the possibility of knocking holes in external walls. New clients may not be fully briefed as to the effect such measures may have.
    Yes, in theory any new hole in an external wall should require a new airtightness test. In reality it depends on the existing test value, I suspect, and the size and nature of the hole! Small hole drilled for a new cable, not so much of a problem when sealed. New door or window fitted, absolutely should be retested.

    Posted By: JontiMy understanding is PH certification is for 'as built' not that it something that needs reassessing which is over thinking it in my opinion.
    I think it's 'as built' too. But the airtightness in particular is likely to degenerate over time to some extent. For example, one of our external doors (well the door frame in fact) has warped a little bit so is likely not as airtight as it was. Now our airtightness test was well under the limit, so we'd probably still pass, and I'm not too concerned as a practical matter because that door opens into our conservatory, which is also airtight and triple glazed etc.
    •  
      CommentAuthordjh
    • CommentTimeMar 4th 2022
     
    Posted By: WillInAberdeenSame as with EPCs, the difficulty is to recertify the energy performance if the present owner doesn't have evidence of all the construction materials and details. If the surveyor cannot see what insulation is under the floor or in the walls, or see certificates for the windows and appliances, they have to assume the worst.

    The resulting certificate may be disappointingly poor, which (it is intended) would have financial consequences.
    Yes, AIUI even if you do have the details they don't rerun SAP they still have to use the even more brain dead rdSAP. It's another reason I don't like EPCs.
    • CommentAuthorEd Davies
    • CommentTimeMar 4th 2022
     
    Posted By: djhFor example, one of our external doors (well the door frame in fact) has warped a little bit…
    No problem, just make sure they use that door for the pressure test :devil:
    • CommentAuthorJonti
    • CommentTimeMar 4th 2022
     
    Posted By: owlmanWith no ongoing certainty of the house performance therefore, using PH as a selling point perhaps should carry a health warning; a case of caveat emptor.


    Though I understand what you mean it seems pretty unrealistic to expect any property to recertificate. PH is a building standard and not a performance check. Can you imagine if every time a house was sold it had to get a building regs certificate for it.

    It is a guarantee the house was well built though which is better than most.
    •  
      CommentAuthordjh
    • CommentTimeMar 4th 2022
     
    Posted By: Ed Davies
    Posted By: djhFor example, one of our external doors (well the door frame in fact) has warped a little bit…
    No problem, just make sure they use that door for the pressure test :devil:
    Indeed! :) Sadly for PH all they need is a small window opening rather than a door. Paul used the window in our downstairs shower for his fan.
    •  
      CommentAuthordjh
    • CommentTimeMar 4th 2022 edited
     
    Posted By: Jonti
    Posted By: owlmanWith no ongoing certainty of the house performance therefore, using PH as a selling point perhaps should carry a health warning; a case of caveat emptor.


    Though I understand what you mean it seems pretty unrealistic to expect any property to recertificate. PH is a building standard and not a performance check. Can you imagine if every time a house was sold it had to get a building regs certificate for it.

    It is a guarantee the house was well built though which is better than most.
    Yes, I agree, and caveat emptor is de rigueur when buying a house anyway! But it's legally required to have an up-to-date EPC when selling or letting a house these days, so it wouldn't be completely unreasonable to require a recent confirmation of a PH certificate (whatever that means!) if it was being used as a sale point.

    edit to add: The current nightmare with selling/valuing/insuring/etc flats also indicates the problems that can arise when current practice varies from what legislation requires, although in this case it's clearly the legislation that is faulty.
    • CommentAuthorJonti
    • CommentTimeMar 5th 2022
     
    But does an updated EPC include an airtightness test? As far as I am aware an EPC goes on what has been reportedly put into the building's structure such as insulation, glazing, etc. I don't believe there is an actual performance test as there is with a PH certificate. PH is a lot about quality of build but I am not sure EPC is.

    If the test/certificate ends up costing more than the increased value then why bother in the first place especially as you will need the EPC as well.
  4.  
    No airtightness test for a 10-yearly EPC update using rdSAP.

    They are based on whatever construction details are visible to the surveyor without making holes (eg loft quilt), or the following evidence of insulation if the householder can produce them during the survey. Otherwise they are just based on the age of the building.

    "Acceptable documentary evidence includes certificates, warranties, guarantees, building regulation
    submissions and official letters from the applicable Registered Social Landlord (RSL). The assessor
    must be able to demonstrate... [they] relate to the actual property being
    assessed" (SAP 2012 app S)

    Note that construction photos taken by the (previous) householder do not count, eg as evidence for DIY insulation, or for details that exceed building stds/regs.

    Based on this the re-certification would not look as good
    as the original, if that affects the resale value.


    Edit: not just 'buyer beware' but also 'lender beware' - if a property is priced high because of claimed low energy bills increasing the buyer's ability to afford repayments, the mortgage company might like some reliable evidence of that to support the higher valuation, before they are able to lend out the extra capital. Be interested how they would look upon a 10 year old EPC or PH cert in that case.
  5.  
    Both PH and EPC are theoretical. Surely more relevant to, say, a 5 year old house whether certified or uncertified, are the actual energy costs/usage.

    My energy supplier has gives me an annual statement showing energy used, cost, and forecast for the coming year. Surely that's the most relevant data (and for anyone with solar would take production into account as well). My experience of moving from a house to a small flat and back to a house while we built showed our electricity usage didn't change much (fridge/freezer is a constant and the largest component, likewise number of hours/rooms per day with electric lighting on). In a very well insulated/passive house the internal temperature doesn't vary that much so theres much less to be gained by having the heating 'on' for only a few hours a day as there is in a poorly insulated house .
    •  
      CommentAuthordjh
    • CommentTimeMar 7th 2022
     
    Posted By: Simon StillBoth PH and EPC are theoretical. Surely more relevant to, say, a 5 year old house whether certified or uncertified, are the actual energy costs/usage.
    The problem with in-use figures is that they are subject to arbitrary variation according to how warm people keep their houses so can be manipulated deliberately or simply unknowing.

    The PH model has been demonstrated to be a lot more accurate than the garbage that is EPC.

    Energy suppliers forecasts are completely unreliable, at least in our case. I left Bulb early this year after an extended argument with them about their unrealistic forecast for our future usage. They weren't interested in our years of consistent logged actual data and refused to cut the projected payments to a reasonable level. So I moved.

    I'm happier with Octopus (well Co-Op) but their forecasts seem to be just as bad. I haven't engaged with them yet about it because we're on a fixed tariff. I suspect their models make assumptions about houses being 'average' that simply don't apply to ours, but that's just my speculation. This year, by coincidence, I've also changed my rules about when we put the heating on so I expect my bill this year will differ somewhat from the pretty consistent figures from previous years.
  6.  
    Posted By: djh
    Posted By: Simon Still
    Energy suppliers forecasts are completely unreliable, at least in our case. I left Bulb early this year after an extended argument with them about their unrealistic forecast for our future usage. They weren't interested in our years of consistent logged actual data and refused to cut the projected payments to a reasonable level. So I moved.
    .


    that's interesting. Bulbs forecasts for use for me were fine, with the costs going up (which turned out to be correct. However, I think when they were going under they were upping everyones monthly payments to try to give them more cashflow. When I asked for a refund they insisted I kept at least one months costs in credit
   
The Ecobuilding Buzz
Site Map    |   Home    |   View Cart    |   Pressroom   |   Business   |   Links   
Logout    

© Green Building Press