They slipped this out quietly... well at least I heard nothing until I went looking!

http://www.planningportal.gov.uk/uploads/br/BR_PDF_ADL1A_2010.pdf

First thoughts? Not sure, still reading and digesting it.

Timber

U values seem no where near low enough to me --- 0.3 for walls???

Air leakage is still a joke at 10 -- it thought it was coming down to 5?

They now mention thermal bypass and thermal bridging which is good.

I wonder if it will all get taken on board?

Mike - The % improvement is still relating back to ADL2002, and so 44% improvement for level 4 will remain the same.

I am supprised as well by the U values and air leakage, still no where near good enough.

U values for party walls is good, although it is based on results from masonry buildings and does cause some issues for larger scale timber frame buildings.

Timber

Posted By: Joiner
EVERY type of window made will need a compliance certificate available (under the proposed regime) only from BFRC. Look on their website and see what you need to do to get the label that BC will be looking for.

Yes, every one of my windows is a one off. There is no way that my windows are going to get certificates. My customers will just have to be outlaws.

Am I bovvered?

Also I can't see anything that covers replacement windows. I searched for replacement and got nothing. Nor historic buildings. Searched for that and also got nothing.

Hi Countryman. Replacement windows would be covered in Part L1b I believe, though I havn't read that one yet either. Link here: http://www.planningportal.gov.uk/uploads/br/BR_PDF_ADL1B_2010.pdf

Thanks Mike. There is light at the end of the tunnel - ref section 3.6 on.

Just leaves the issue of proving competence, which hopefully will see the return of local authority "preferred" trademen lists which have been abandoned in Shropshire in favour of a Trader Register administered by Trading Standards that just requires you sign up to a code of practice, whereas to get on the old lists you were "invited" to join having "come to our notice".

The problem with the exemptions as outlined in section 3.6 on is that it makes arguable the case for those buildings of acknowledged historical interest which are neither Listed nor in a conservation area. We've all had our share of those and it's only been the supporting letter from the CO which has kept BC off our backs. I doubt there is time enough between now and October to get those 'outliers' under the umbrella of conservation, given the amount of paperwork and the statutory-notice delays that it involves.

Small mercies I guess! Forgive me if I appear ungrateful. lol.

Looks like you're spot on there Countryman. I have a nice database of window u-values in Tas so will check to see if it agrees with SAP 2005, though I am pretty sure it will

Hang-on, so new builds only need windows that meet U=2W/m2.k, but replacement windows must be less than U=1.6W/m2.k?

Why on earth are new builds allowed to fit double glazing, while someone replacing their window isn't?

Is this just pressure from the mainstream house builders that don't want to have to fork out the (perceived) extra for triple glazed?

Tony....sad to say that you're wrong. The double glazing salesmen are going to have a field day.

Why? Simple. It is a lot easier to get a Windows C rating with its' fudged calculations and dubious science then it is to say 'I have an overall window U value of 1.6'. I think.

If I'm wrong then they will be replaced by Triple Glazing salesman and I can see the hype already. We are going to be submerged in a sea of plastic windows and I for one am deeply depressed.

I was right. Sticking in a design where the frame is 10% of the overall window area, a total solar energy transmittance of 65% and a fairly breezy air leakage of 1 gives a requirement for the overall u value for a window to be around 2. This is easily achievable with bog-standard uPVC double glazed windows.

So small joinery companies...please go and sign on the dole now.

Posted By: countrymanTrouble is, if you replace windows, then aren't you supposed to notify Building Control?

Yes. The truth is that it has been known for someone not to bother, and thus saving themselves the ~£70 fee.

Hereabouts the BC fee is twice that for work costed at UP TO £1,000!

The last job I did was £3,700 and the fee was £236.18, which the customer paid separately.

The problem with avoidance is that it lands the customer with a potentially embarrassing situation when they come to sell unless they're prepared to lie.

Indeed. But a £236.18 fee on a window replacement that cost £600 is a bit of an incentive to live the life of an outlaw. It's a mad bad world.

To pick up on a few comments. It is not a question of 'you submitting your design to BC'. In the old days when we just considered the 'u-value' of the dgu (double glazing unit) then it was as simple as reading the u-value tables and making sure that you stuck in a dgu that met the criteria. Job done.

But now...for whatever reason..the Govt has dreamt up the Windows Energy Rating scheme. My own suspicious mind is that it is tied in with being seen to be meeting carbon footprints etc as far as the EEC is concerned. So what has changed? Now that the WER scheme is in place, each window requires a certificate of compliance. That is what the BCO will look for...not that the dgu is 4:24:4 whatever. To get a window certified, you have to get your window tested. That costs money. Next you need to be ISO9001 certified so that you are 'accredited' to making the windows to the same spec as that which was certified. That costs more money. Then you also have to be audited to make sure that you are still making the windows to the certified spec. That also costs money.

That is fine for the big boys. They amortise it across hundreds if not thousands of windows. But for a small joinery company, it simply isn't practical. For a start there is all the additional cost and red tape as I have explained. And that is for just one window. When the next customer comes along and wants a slightly different window then my understanding is that you'll probably need to get that window also certified. So back to square one. I will return to the WER scam...erm, sorry, scheme..in a moment.

OK - so Mr Small Joinery doesn't want to go, for very good reasons, down the WER certification route. He can make a window as long as it has an overall u-value of 1.6. This is draconian and simply unfair. New builds only have to meet 2.0. Talk about a non-level playing field. To make a window with this low u-value, he needs to fit very expensive double-glazed units. To meet 1.6 with an average frame needs a dgu of something like 1.1. ie krypton filled. Or something like Optitherm or Planitherm with argon. Interestingly this type of dgu also would allow the more straightforward third alternative for window approval...ie central-pane u-value of 1.2.

If he is going down the 'I meet 1.6 u-value overall route' then he will also need to invest in the software that allows him to calculate the overall u-value so that he can give the BCO a printout showing that he has met the 1.6.

OK - back to the WER scam....must stop doing that....scheme. The formula for this is in L1B. It introduces into the heat-loss equation things like solar gain and air leakage. It also uses the overall u-value of the window. The topic of solar gain and the maths behind it is basically sound but there is strong evidence that the Govt has fudged the figures and not applied the same well-researched and peer-reviewed scientific equations but have made up their own. They have been asked by many people to produce the science behind their 'new improved' figures but have, to date, refused to do so. Wonder what happened to the Freedom of Information Act?

OK - leaving aside the dubious 'science', if you plug in typical values for solar gain and air leakage (as I did in my earlier post) then to get a WER 'C' rating, all you need do is have an overall u-value of 2. So how come they are demanding an overall u-value of 1.6 if you don't have a WER certificate? Double-standards spring to mind.