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Green Building Bible, Fourth Edition
Green Building Bible, fourth edition (both books)
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    •  
      CommentAuthorfostertom
    • CommentTimeAug 12th 2009
     
    Sure, but 2 steps forward, 1 back - by then everyone will know that it's technically possible, and nearly economic - so next time .... At least revised SAP will have become as useful and widely understood as PHPP.
    • CommentAuthoraa44
    • CommentTimeAug 12th 2009
     
    Coming at it from a slightly different perspective, I have been trying to find out who makes the most weather resistant windows. I live in Shetland and wind driven rain is a major issue. NorDan are much in favour with local architects as experience shows that they keep the water out. The British and DIN standards specify that the windows should withstand wind driven rain at at least 600 Pascals pressure (if I have understood it correctly). NorDan claim to withstand 3200 Pa and Adpol 2000 Pa. I have just spoken to somebody from the Rawington HQ in Germany (?) who said that they only test to the standard, i.e. 600 Pa so I have crossed them off my list. I am waiting for a reply from Internorm.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 12th 2009
     
    Posted By: Marenthe best way to insulate a cavity built 1930's bungalow? And the extension?
    Without seeing it, piece of cake - EWI (external wall insulation) - 150-250 EPS (expanded polystyrene) or wood fibre board (see NBT -Natural Building Technologies) applied to the outside face, rendered, £75 to £95 per m2. Resist cavity wall insulation - totally inadequate insulation and empty cavities are a thermal asset if filled with clean shingle or weak concrete inboard of EWI. The extension's walls can be built of solid aerated blockwork (available in e.g. 255 thickness to match an old cavity wall thickness, and in 215 high courses because so lightweight a mason can easily handle big blocks) finished with the same EWI, seamless with the extg house's EWI. Carry the EWI right down to the top of the strip found, with just a nominal 25mm of EPS insulation under the new floor. Roof - insulate between the rafters, preferably blown-in Warmcel, after laying 9mm OSB glued and screwed over the rafter tops, 100-150 EPS over that, jointless with the wall EWI, secured with downslope battens, breather felt draped over, then tile and batten.
    • CommentAuthorvalasay
    • CommentTimeAug 12th 2009
     
    Hello Maren,
    I've just got my quote from Broxwood, and they look like they'll be around 1500-2000 (20%) cheaper than Internorm by the time the door quote comes through (they're pricing windows and doors separately)Lead time is 10-12 weeks though.

    That's a good point aa44,I must check up on that too...
  1.  
    Posted By: fostertom
    Posted By: Marenthe best way to insulate a cavity built 1930's bungalow? And the extension?
    Without seeing it, piece of cake - EWI (external wall insulation) - 150-250 EPS (expanded polystyrene) or wood fibre board (see NBT -Natural Building Technologies) applied to the outside face, rendered, £75 to £95 per m2.


    I agree with the suggestion of external insulation if you can afford the space.

    Just watch out on your material choice - for the same level of insulation that's 150-250mm EPS or 275 to 375mm of wood fibre board. (EPS=~0.3kW/mk, wood fibre board=~0.45kW/mk).
    • CommentAuthorMaren
    • CommentTimeAug 12th 2009
     
    Thanks fostertom and MarkBennet: Is external insulation still a reasonable option if I only have space on two sides of the house? Third side next to an already extremely narrow driveway with no space left to sacrifice, fourth side will be the extension.

    My parents in Germany had external insulation (EPS plus render) put on their house and the effect was impressive, noticeable even before the heating bills came in. I was told though that external insulation (which I favoured thanks to my parents very positive experience) would prevent the cavity walls from breathing - how would you account for that?

    Thanks valasay, for the update, have sent an enquiry to Broxwood today but with those lead times I may not be able to order from them. Although I did read in Rawington's brochure that alu-clad windows should only be put in after absolutely every other messy job was done as render or plaster may damage the windows. Have you been told anything about that?
    •  
      CommentAuthorfostertom
    • CommentTimeAug 12th 2009
     
    Posted By: MarkBennettEPS=~0.3kW/mk, wood fibre board=~0.45kW/mk
    Bit closer than that AFAIK:
    EPS Platinum (extra cost) 0.030 or a bit worse
    EPS standard 0.038 av
    Pavatherm 0.038 is used in tandem with Pavatherm Plus 0.042, so 60 + 60 gives 0.040, 100 + 60 gives 0.0395.
    So 150 or a little more EPS Platinum is equiv to 190 EPS standard is equiv to 200 Pavatherm.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 12th 2009
     
    Posted By: MarenThird side next to an already extremely narrow driveway with no space left to sacrifice
    OK, that's where 'without seeing it' comes in - think of something else maybe internal for the Grd. Fl, return to EWI for 1st. Fl, tho it's a double pity to suddenly bring the insulation line inboard - creates lossy thermal bridging situation. Consider extremely insulative (therefore only one third as thick) but expensive Aerogel for that wall. Obviously not he fourth wall you're building against, except above its roof line, if lower?

    Posted By: MarenI was told ... external insulation would prevent the cavity walls from breathing
    Rubbish - EPS is adequately breathable, Pavaclad very breathable. Closed-cell XPS (extruded polystyrene) and the other foamed plastics are not breathable and cost more. You'd need to use XPS below GL, down to top of strip found.
  2.  
    Posted By: fostertom
    Posted By: MarkBennettEPS=~0.3kW/mk, wood fibre board=~0.45kW/mk
    Bit closer than that AFAIK:
    EPS Platinum (extra cost) 0.030 or a bit worse
    EPS standard 0.038 av
    Pavatherm 0.038 is used in tandem with Pavatherm Plus 0.042, so 60 + 60 gives 0.040, 100 + 60 gives 0.0395.
    So 150 or a little more EPS Platinum is equiv to 190 EPS standard is equiv to 200 Pavatherm.


    OK, I agree I was probably being optimistic on the EPS.

    Reverse engineering Pavatherm from the numbers quoted on NBT's web site gives 0.045 for Pavatherm plus and 0.036 for Pavatherm. I'd only considered the Pavatherm Plus (thinking it would be better than Pavatherm). (Interestingly NBT quote their numbers as k-values, not u-values. Is there any subtle difference, or are they interchangeable in this context?)

    Note that GreenSpec lists wood fibre board as being 0.08W/m.k (http://www.greenspec.co.uk/html/materials/insulation.html). It lists EPS as being 0.032 to 0.040, which is in line with your numbers.

    Anyway, the basic argument is the same. You are likely to need more natural insulation to match the performance of "plastic" insulation. It could be a problem if space is tight.

    Interestingly Greenspec also quotes the embodied energy of wood fibre board being much higher than that of plastic based insulation - even PIR, especially when you need more of it to get the same level of insulation. These figures must be wrong, surely?

    (BTW - I admit guilt for erroneously slipping the extra 'k' into the units in my original numbers....)
    •  
      CommentAuthorfostertom
    • CommentTimeAug 12th 2009 edited
     
    p38 of http://www.natural-building.co.uk/PDF/Pavatex/Pavatex%20Walls/090128_Technical_Manual_Masonry.pdf gives the 0.038/0.043 Pavatherm nos. They seem to put at least 60 PavaPlus on the outside, then add PavaOrdinary (better insul, presumably cheaper?) behind it for thicker installations. Greenspec's giving strange figures!

    k- (nowadays shd be renamed lamda-) and u- not interchangeable - u is k but with thickness added into the calc.
    •  
      CommentAuthordjh
    • CommentTimeAug 13th 2009
     
    This is an excellent topic called "Alu-clad wooden window quotes received - help"! Could you guys having an also interesting discussion about a completely different topic, please put your discussion in its own topic?
    •  
      CommentAuthorfostertom
    • CommentTimeAug 13th 2009
     
    Can you ever do that for us Keith - fish out off-topic bits and dump into a new thread?
    • CommentAuthorMaren
    • CommentTimeAug 13th 2009 edited
     
    Update on price:

    ecomerchant triple glazed, alu-clad all else the same £7220 inc VAT&Del (£6036.40 ex VAT)

    This is so far the most competitive quote but what is the verdict on ecomerchant's windows (made in Germany)?

    Also the U-values are given as 1.26 to 1.32 for the whole window triple glazed. Best U-value of 1.26 is for the patio doors, where I have not asked for trickle vents.

    fostertom and anybody else who knows: do the trickle vents make a big difference for the U-value? I will not have mechanical ventilation in the extension so have to include those. Has building control ever accepted the Rawington style almost closed and securely locked trickle vent position (see Tuna's post on page 1) in lieu of trickle vents?
    • CommentAuthorsquowse
    • CommentTimeAug 13th 2009
     
    a certain amount of trickle ventilation is a requirement of the building regs for new build. either 4000 or 8000 mm2 per room. these are vents that are fitted through the frame, destroying the airtightness you have been working hard to achieve. the good news is that a) you can close them if the ventilation is not desired and b) they are completely secure, unlike the "night vent", open a fraction position of windows (that you are referring to as "the trickle vent effect".
    the trickle vents are not taken into account when measuring U value. and they are not a requirement per window, but per room.
    • CommentAuthorMaren
    • CommentTimeAug 13th 2009
     
    squowse - I appreciate you answering twice to the trickle vent issue. It's good to know that these vents are not taken into account when calculating U-value - it does mean that ecomerchant's windows must be losing heat somewhere else then to have such high U-values for triple glazing.

    Have since spoken to building control and they will not accept the slightly open position - mechanical ventilation or proper trickle vents only but he did advise that some extractor fans for kitchens come with trickle vents so I'll check those out. BTW, he actually remarked it made no sense to increase heat loss that way when you try for best possible U-values and airtightness but that we had to stick to the regs nonetheless.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 13th 2009
     
    Long time since I specd trickle vents - Bldg Insps not given trouble, seem happy with the open-a-ctack lockable window position. And why not? - what's the difference between that and a trickle vent? Trickle vents are made cheaply, so have no chance of being airtight when 'closed'.
    • CommentAuthorsquowse
    • CommentTimeAug 13th 2009 edited
     
    well they aren't really intended to be closed i suppose.
    interesting you had no building regs problems with no trickle vents. is that new build? was there another arrangement for ventilation?
    •  
      CommentAuthorfostertom
    • CommentTimeAug 13th 2009
     
    Ambitious extension/uprating mainly. The only venting (other than kit/bath fans) being the open-a-crack cockspurs.
    • CommentAuthorTerry
    • CommentTimeAug 14th 2009
     
    Our BCO was also happy with no trickle vents. He was happy to accept the open-a-crack type windows as well. we have MVHR though, which was also fine by him.

    I think many BCO's prefer to suggest trickle vents since it is the standard in this country so makes life easy for themselves and they probably worry about the majority of people who dont give ventilation a second thought and would close the windows without realising the impact it would have.
    • CommentAuthorvalasay
    • CommentTimeAug 15th 2009 edited
     
    Hi Maren,
    Just to add to my earlier posting about aluclad costs, windows were cheaper at Broxwood than Internorm but doors were the other way round making total costs roughly the same. Haven't heard yet from Russell Timbertec or Rawington.

    Haven't heard anything specific about plaster/render causing damage but my builders were wanting them towards the end of the refurb
    • CommentAuthorMaren
    • CommentTimeAug 20th 2009
     
    Update on eco-merchant:

    Triple glazed all-timber £5087 inc VAT,
    factory applied discount of 15% included on all eco-merchant prices I had so far

    I have to correct my first posting though, these are not made in Germany but in Estonia by Viking AS http://www.viking.ee/en//

    Tuna: Rawington has offered another (lower) quote but using System 4000 (this is an aluminium profile that clips onto grooves in the timber frame). Which System are you using?

    Rawington alu-clad (system 4000) £6508 inc VAT&Del
    Rawington triple-glazed all-timber £5187 inc VAT&Del

    valasay: thanks for the update, have not heard back from Broxwood yet at all. I am also still waiting for the quotes for all-timber triple glazed from Russell and Nordan.

    Have been advised by eco-merchant that the glazing bars affect the U-value. Does anybody know by how much?
    • CommentAuthorTuna
    • CommentTimeAug 20th 2009
     
    Our quote is mainly for Miratherm windows, with system 4000 used for French doors - we've mixed and matched a bit to get the doors opening the way we want, level thresholds and so on. We're also having the frames made in oak rather than engineered timber, which adds to the cost.
    • CommentAuthorvalasay
    • CommentTimeAug 21st 2009
     
    I've just got my quote from Rawingtons. Very good price £2000 cheaper than the rest (Internorm and Broxwood)so far. The quote is for Nordwin windows. Can anyone tell me how they compare with the rest of their products. Is it a budget version?
    • CommentAuthorMaren
    • CommentTimeAug 21st 2009 edited
     
    Tuna: thanks for the info, I was wondering if this was some totally unknown system, but have now found details on the manufacturer's website as well. What level thresholds are you looking for? We want an external door with level threshold and french doors with level thresholds. The external door is for my utility room so I would ideally like this to be a tilt and turn door but nobody seems to be able to do a level threshold for tilt and turn doors. Probably technically impossible? I am sure the oak will look beautiful - our budget won't stretch any further after chosing wood instead of our usual PVC! But that alone makes me feel happier, I just hope the windows will really be better than the PVC we bought for our last two houses and worth the money.

    valasay: As far as I know Nordwin is the brand name of Rawingtons Mira and Braga windows at the manufacturer's website: http://www.gutmann-international.com/hgw/index_en.html

    This catalogue shows some (or all?) technical details of the Nordwin windows; the link is to a different website as I could only find this catalogue in German on the Hermann Gutmann Werke website.
    http://www.beslagskonsult.se/downloads/catalog_nordwin.pdf
    • CommentAuthorTuna
    • CommentTimeAug 22nd 2009
     
    I can really recommend asking to see a sample window, whichever system you choose. Then you can get a sense for how the wood will look (engineered timber windows will have finger joints on the frame surface), and the quality and feel of the ironmongery.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 22nd 2009 edited
     
    Possible to get agreement that no finger joints will be visible on the inside and/or outside face. Doesn't matter anyway in not clear-finished.
  3.  
    This thread is inadvertently highlighting some of the pitfalls that can befall the inexperienced consumer.

    If you are planning on spending significant sums of money on windows and doors that may be advertised as ‘Windows for life’ and similar, you would be well advised to make sure who has actually made the products and what warranties are in place. Is it a manufacturer’s warranty or something offered by a local agent? If the local agent goes tits-up – not unknown in the industry - will the warranty by honoured by the manufacturer? What quality standards does the manufacturer operate and what certification do they have for their products? Are the products suitable for UK climate/construction conditions? Is safety glass used in the required locations and is it marked properly as required by Building Regulations?

    I have seen one particular product advertised in this thread that is setting off alarm bells. The Nordwin catalogue that has been linked is not designed for consumers. It is a product specific catalogue produced by a systems company for window manufacturers. Gutmann, a highly reputable company, do not manufacture windows. They design systems and produce window components. I looked further into the company associated with the windows in the UK. They are not a manufacturer. There is no mention of who actually makes the windows or what country they are made in and who certifies the quality of the finished product -as distinct from the components. The only director I can find seems to be a Latvian chap. There is no record of the company on the IFT-Rosenheim database of certified manufacturers. No listing with BBA (or even the BFRC for what its worth).

    Caveat Emptor would be my advice.

    Furthermore the company feature a prominent Secured by Design logo on their homepage – a valued quality mark in the window industry. This is misleading as upon reading the small print it only applies to the ironmongery. Using ironmongery that has SBD approval does not confer SBD status to the whole window. I will be drawing this matter to the attention of SBD. Inspector Knacker takes a dim view of this sort of thing.

    Monty
    • CommentAuthorMaren
    • CommentTimeAug 28th 2009 edited
     
    Price Update:

    Rationel windows supplied by ADW Ltd in Cumbernauld: £5904 ex VAT.

    The U-value for these alu-clad, double glazed windows is given as 1.4 (average), these are the only windows
    built 6-22-4 with warm spacer (and argon filled).

    I am quite taken with these windows, especially as the vents disappear into the frame when closed and are invisible from the outside. Have now been advised by two companies that the glazing bars worsen the U-value, whereas Nordan said no (probably the way the bars are added?) so asked for price and U-values without them from ADW Ltd for the rationel units.

    Nordan: triple glazed alu-clad £6235 ex VAT.

    Russell Timbertech: triple glazed all-timber £5719 ex VAT (but only with outward opening doors, not with tilt and turn inward).

    Still waiting for Broxwood and Alba quotes

    Tuna: thanks for the tip will try and see the windows with the local suppliers but might struggle with those further afield. Unless they send out samples?

    Fostertom: we are not so bothered as we will indeed be going for either a dark stain or opaque finish but I'll keep this in mind for the future.

    Monty: thanks for your concern. I posted the Nordwin catalogue in response to valasay to show that Nordwin was the particular name given by the Hermann-Gutmann-Werke to the same aluminium profiles discussed earlier (Braga and Mira) as made specifically for the Scandinavian/British market. You are right of course that this says nothing about the actual timber frame or glazing units.

    We did buy from a very well known company using unsavoury practices when we bought our first UPVC windows. Lambs to the slaughter, we fell for every single marketing gimmick. The windows themselves were okay but so badly installed, ants kept walking through the gaps and the wind made very strange noises blowing through the gaps between frames and walls on one side of the house and out the other side of the house. When we phoned the company to rectify the proble (same name, same phone number) we were told the company was bought over and the warranties no longer valid. Which was not quite true as we found out later but we certainly did not take them on. We fixed the gaps ourselves instead.

    Do you have any insight on the Rationel windows?
  4.  
    Any look with my Estonian friends?

    J
    • CommentAuthorMaren
    • CommentTimeAug 28th 2009
     
    James: still waiting for the quote
   
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