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.

Buy individually or both books together. Delivery is free!


widget @ surfing-waves.com




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.




    • CommentAuthortony
    • CommentTimeJan 31st 2017
     
    This is something that we should talk about

    A good review of the review here http://www.sustainablehomes.co.uk/the-bonfield-review-better-late-than-never/?utm_campaign=SHIFT+Awards+2016&utm_source=hs_email&utm_medium=email&utm_content=41667821&_hsenc=p2ANqtz-82Alw0vgLi9Jvnu9oT8xUVqbnXIkqGCmIkRJhEFHp2vy_afgp4CCGUKVwg0P-Yy9ZzfIZodYUYARYozvPJPhjZ-Rqi7w&_hsmi=41667821

    The review is making good points and I hope that result in changes like enforcement, monitoring and better buildings.
    •  
      CommentAuthorSteamyTea
    • CommentTimeJan 31st 2017
     
    • CommentAuthortony
    • CommentTimeJan 31st 2017
     
    Having skimmed through it several things worry me

    A) a new standard -- the standard

    B) No SMART targets, promote, encourage etc with no numbers or real targets.

    C) Social housing gets a mention at the bottom of the paper :cry:

    More to come if I can muster the enthusiasm to plough through it -- I hope it works but can't see it curing the mustard
    • CommentAuthorgravelld
    • CommentTimeFeb 1st 2017 edited
     
    It's a report very much aimed at fixing problems with the quality of delivery, which is fine as far as it goes.

    It's nothing to do with fixing the quality of homes, which is what is actually needs to be fixed.

    It just another talking shop and consultation involving as many people as possible leading to a watered down yet somehow byzantine nonsense for which the outcomes will be complex and very limited.

    I've come to think that's how Government prefers things; it means it doesn't need to do much as a result, or tackle the hard problems, like how to retrofit the almost-entire building stock, which is the problem that really needs to be solved.
    • CommentAuthorSigaldry
    • CommentTimeFeb 1st 2017
     
    Actually the 'talking shop' was in reality a number of workstreams that fed up a lot of good ideas and recommendations and suggestions and also quite a lot of detail - however brevity and politics got in the way of a much quicker release and a more detailed set of recommendations.

    The process is continuing and should drive changes, so overall positive I feel.

    The importance of Survey, Design, Specification and Installation and also Consumer Confidence, Redress and Guidance all got covered.

    I'd also have liked to have seen more to drive up the energy efficiency of homes for the general populace and suggestions for better policies and nudges to encourage appropriate, quality improvements to happen.
    •  
      CommentAuthordjh
    • CommentTimeFeb 1st 2017
     
    I've seen a couple of large-scale planning applications lately that make a feature of being 'energy efficient' but when you read the small print, they ascribe the energy efficiency to meeting current building regulations! :devil:

    I think there's quite some gulf to bridge.
    • CommentAuthorDarylP
    • CommentTimeFeb 1st 2017
     
    as big as 'of Mexico'.....:bigsmile:
    • CommentAuthorEd Davies
    • CommentTimeFeb 1st 2017
     
    Current building regulations actually done properly plus reasonable airtightness would be pretty decent, though.
    • CommentAuthorringi
    • CommentTimeFeb 1st 2017 edited
     
    I agree with with Ed Davies, if there was just no gaps in the insulation and air tightness that lasted then I would not be too unhappy with the Part L standards. Therefore a requirement for the air tightness testing to be repeated at the end of year 5 and 10 on 100% of the homes, along with surveys with a thermal image and the builder having to fix the issues found may be all that is needed.

    As soon as the quality of insulation can be trusted so that running costs are what the EPC says they should be, then the EPC rating may drive improvements to insulation standards.
    • CommentAuthorgravelld
    • CommentTimeFeb 1st 2017
     
    Exactly.

    We know what the problem is.

    We know what the solution is.

    Building high performance housing is a technically solved problem. Even retrofitting them, albeit more difficult, is solved. We know we can do it because it's been done enough times before.

    The reason we have constant consultations and "what went wrong" sessions is partly because we continue to do things by... not even halves... tenths... of what we have to do. These "stake holder" groups try to derive "value" and "ROI" based on a set of assumptions which are by no means natural and are instead driven by what Government is telling channeling them to come to.

    So when I see some administrator draw up another executive summary of the ideas in a few people's heads and "nudges" (arghhh!) that might move the needle 1%... sorry, that might work for top line sport where fine margins are important, but we aren't talking margins here, we're talking vast gulfs between where our housing stock is and where it needs to be.
    •  
      CommentAuthordjh
    • CommentTimeFeb 1st 2017
     
    My memory is that current regs are nowhere near where we need to be for one-planet, but maybe my memory is faulty.
    • CommentAuthortony
    • CommentTimeFeb 1st 2017
     
    +1 for both the last two posts, and yes the regs are nowhere close
    • CommentAuthorDarylP
    • CommentTimeFeb 2nd 2017
     
    The 'regs', ie Part L Building Regs, and partly Part F, are not enforced properly, regardless of what they purport to regulate.
    Building Control officers (both LA and Approved Inspectors) are desperate for business, and so not going to bite the hands that feed them, are they......:cry: So as long as they have insurance backing, the temptation to let things 'slip' is too great.
    Coupled with a lack of training / CPD / call it what you will, in the building construction industry, this means mistakes & short cuts will still occur....:sad:
    • CommentAuthorEd Davies
    • CommentTimeFeb 2nd 2017
     
    DarylP, can you do any calculations of the energy requirements of a sensible [¹] house to current building regs but with Passiv levels of airtightness?

    While tightening up the U-values (particularly for windows) in building regs would probably be a good thing I really don't think that's the top priority.

    [¹] Reasonably compact shape, perhaps half a semi, not too much glazing, 100 m² or so finished floor area.
    •  
      CommentAuthordjh
    • CommentTimeFeb 2nd 2017
     
    There was a comparison done against 2010 regs that may be helpful:

    http://www.bere.co.uk/sites/default/files/research/16PHT_Nick%20Newman%20submission.pdf

    It assumes of course that buildings are actually built to the standards.
    • CommentAuthorDarylP
    • CommentTimeFeb 2nd 2017 edited
     
    @ Ed Davies, I have loads on the server to pick from, I can vary Air permeability / Air tightness with a click of the mouse, and the same with U-values.
    The biggest 'movers' are now air-tightness, which is the one thing that the developers/contractors can influence/improve,
    and Psi-values (thermal bridging) which are fixed once the Arch's / Designers have done their thing.

    But as said above, it only 'works' if the dwelling is actually built as designed.
    :bigsmile:
    •  
      CommentAuthordjh
    • CommentTimeFeb 2nd 2017
     
    Posted By: DarylPThe biggest 'movers' are now air-tightness, which is the one thing that the developers/contractors can influence/improve,

    Airtightness is really a design-time thing as well. If a building isn't designed with an airtightness layer, it can be very difficult (impossible) to include one later. For sure developers/contractors often make things worse and a design is no good without attention at the construction stage as well. But much the same goes for insulation and to some extent for thermal bridging.
    • CommentAuthorDarylP
    • CommentTimeFeb 2nd 2017
     
    What I was trying to illustrate, is that with a given design, the builder / contractor can pay close attention to site detailing, and aim for 3m3/m2h or better, which will benefit the SAP rating, and thus Part L compliance, when tested.
    However the Psi-values are determined for thermal bridges at design stage, and thus the builder / contractor cannot affect them.....
    But these two items are the biggest areas for improvement in dwelling design with current AD L1A U-values.
    • CommentAuthorEd Davies
    • CommentTimeFeb 2nd 2017 edited
     
    Daryl, I think we're in violent agreement but I was hoping you could run some numbers to support it. That bere study is interesting but a) 2010 regs are worse than 2013 (at least that house wouldn't meet current (2013) Scottish area-weighted U-value maximums) and b) it assumes it's very leaky.

    Their hypothetical part-L house has 3.85 times the gas usage (and 1.2 times the electricity usage) of the hypothetical Manchester Passivhaus. The question is, if the part-L house had the Passivhaus's airtightness how much lower would those multipliers be?

    These numbers aren't great:

    http://www.gov.scot/resource/buildingstandards/2013Domestic/chunks/ch07s03.html#d5e16076

    but if they were enforced and seen as the least you can get away with without actually being thrown in jail rather than as goals to be aspired to I think they'd by OK.

    What I worry is that calls for tighter regulations would just result in these U-values being reduced further whereas it'd be much more productive to concentrate on enforcement and air tightness.
    •  
      CommentAuthordjh
    • CommentTimeFeb 2nd 2017
     
    Posted By: Ed DaviesWhat I worry is that calls for tighter regulations would just result in these U-values being reduced further whereas it'd be much more productive to concentrate on enforcement and air tightness.

    Both of which are difficult. Enforcement costs money; third-party bodies on the ground doing QC as the building is built. Airtightness also costs money, because it necessitates mechanical ventilation (or even more expensive designer passive ventilation) but mainly because many customers dislike the idea of being reliant on non-natural ventilation.

    That's not to say that your view isn't correct nor that I don't support it.
    • CommentAuthorArtiglio
    • CommentTimeFeb 3rd 2017
     
    The current political imperative is to build as many homes as fast as possible. Most trades on most sites are working on a priced basis so houses are thrown up as fast as practically possible by trades with little interest/training in obtaining optimum results.
    In the vast majority of cases , the occupiers of new homes will find energy efficiency is greatly improved on older stock they have lived in and be happy.
    The increased cost and time needed to build homes to a more sustainable homes was effectively the reason the goverment backed off on the introduction of the sustainability codes.
    There is no appetite to enforce current standards as in the drive to conjure up co2 savings all builds will be asumed to have reached the levels required , the last thing needed is real evidence that such homes do not perform as expected.
    • CommentAuthorDarylP
    • CommentTimeFeb 3rd 2017
     
    :bigsmile: +1 with one caveat
    the 'perceived' increased cost and time needed to build homes to a more sustainable homes was effectively the reason the government backed off on the introduction of the sustainability codes.

    Pickles was given / spun duff info wrt the build cost in Wales! where CfSH was mandatory..... :cry:
    • CommentAuthorSigaldry
    • CommentTimeFeb 3rd 2017 edited
     
    The Bonfield Revew specifically didn't cover New Build.

    Zero carbon Hub's design vs As-built work did look at quality and gave a number of recommendations, but they closed when Government decided to ditch Zero Carbon standards for 2016.

    The Zero Carbon standards were ditched on the basis of an impact statement that was amended/revised and costs reduced after the decision was made. The government policy at the time was that no new standards could be introduced without savings to builders elsewhere to balance any increased costs - savings to the occupiers of buildings and to the UK weren't considered.

    Retrofit Standards for England didn't change in 2013.

    Quality of work is desperately in need of improvement for existing and for new build.

    LABC don't have the resources to enforce quality due to funding cutbacks - the money that Building Control and Planning Departments take in is diverted to under-resourced adult social care etc by the Local Authorities, because of government funding cut-backs and it doesn't stay within those departments.

    The reality is that better performing, better designed and detailed homes are possible at minimal additional cost, but with far better outcomes for occupants and the environment, but it's only likely to happen if building standards improve to force the issue.

    Transitional arrangements urgently need looking at to avoid poorer performing housing continuing to be built using them to bank regulations compliance.
    • CommentAuthorringi
    • CommentTimeFeb 3rd 2017
     
    While we insist on having our homes looks the same as 1900 “technology” and keep pretending we can build mass market homes in the open air, using ad hock labor without a repeatable process not much will improve.

    Factory build homes, to a small number of standard designs would give a lot better results, but depends on continues demand as otherwise no one will invest in the factories. Yet in the UK, no one will commit buying identical prefabs at a constant rate for 10 year…..
  1.  
    Posted By: ringiYet in the UK, no one will commit buying identical prefabs at a constant rate for 10 year…..

    https://www.youtube.com/watch?v=2_2lGkEU4Xs

    Couldn't resist it..........sorry!
    • CommentAuthortony
    • CommentTimeFeb 4th 2017
     
    Re costs and building to a good robust low energy standard, it has now been demonstrated that it is possible to do this with no uplift in cost by Exeter City Council for their recent social housing projects.
    • CommentAuthorEd Davies
    • CommentTimeFeb 4th 2017
     
    DarylP and I have been having a whispered conversation about the relative effects of airtightness on otherwise to-building-regs houses.

    The first point which emerged, which I knew but hadn't fully internalized, is that a house that meets the building regs U-values for each of the elements (floor, roof, walls, windows, etc) will not meet the overall requirements. E.g., if you have the worst allowable wall insulation then you have to have a better roof or whatever to compensate. Therefore just looking at the maximum allowable U-values can be misleading.

    Secondly, as I thought, airtightness is the big hole. If you take a to-building-regs house with 10 m/h [¹] air-permeability and improved it to Passiv levels (0.6 air changes/h, strictly, but 0.6 m/h I think for these calculations; it doesn't make much difference) you get a nearly 20% saving in heat loss which, I think, supports the idea that the next stage of improvements in building regs (assuming the government doesn't scrap the whole idea of regulating at all) should concentrate on airtightness rather than U-values.

    Apart from anything else, airtightness is something that can be one-off relatively independently tested whereas checking insulation installation requires continuous on-site monitoring.

    [¹] I.e., m³/m²·h if the cancellation bothers you. It's just the average speed of the airflow through the fabric so using speed units seems quite sensible to me.
    • CommentAuthorEd Davies
    • CommentTimeFeb 4th 2017
     
    Posted By: ringiTherefore a requirement for the air tightness testing to be repeated at the end of year 5 and 10 on 100% of the homes, along with surveys with a thermal image and the builder having to fix the issues found may be all that is needed.
    I know what you're worrying about but I'm not sure the builder should be held liable for how the occupants treat the home for 5 or 10 years. E.g., house is now leaking a bit but patio doors, PV, a satellite dish, power to the garden pond, an outside tap and an extra phone line have been fitted - who's responsible for determining where the leaks are?
    •  
      CommentAuthordjh
    • CommentTimeFeb 4th 2017
     
    I think the 20% is a bit optimistic.

    Currently, houses aren't built with the aim of being exactly 10 m³/m²/h, they're just built at random except that the 'tight' end of the distribution is cut off by making extra holes in the fabric if it is too airtight and would require mechanical ventilation. So I think you're assuming too much benefit from tighter building. That's by contrast with insulation levels that are specifically targetted at the worst case.

    Also, I think we're some distance away from being able to build every new house in the country to passivhaus level of airtightness. I know there are some districts in Germany and Ireland that do require it, but it's not as easy as it seems at scale I suggest.

    Finally, an airtight house needs a mechanical ventilation system so that needs costing in to the comparison on both monetary and carbon basis. Did your 20% allow for that? What ventilation system was assumed (PIV, MEV, MVHR)?
    • CommentAuthorgravelld
    • CommentTimeFeb 4th 2017
     
    20℅ saving? Thought it would be more than that.
   
The Ecobuilding Buzz
Site Map    |   Home    |   View Cart    |   Pressroom   |   Business   |   Links   
Logout    

© Green Building Press