Surely the argument here should have nothing to do with PH, but simply to tighten up BR to demand better insulated homes, that will reduce the buildings demand on resources and the environment...

At the end of the day PH is just a voluntary additional layer of BR.

Posted By: barneyOK, so terrible by what metric ?

It's a good point - some measurement would be handy to see how bad the problems are. But who would do them? The nationwide organisations are already embedded in the current market dynamic, and don't want to rock the boat. Anybody I haven't thought of?

But I can turn it around:

Posted By: barneyA Part L, Part F compliant house built today at a reasonable cost is still a reasonably well performing building as an entity - greening the grid makes it more so (as would excess electricity to gas production)

Compliant by which metric? Do you have proof these buildings are compliant?

Compliant by which metric? Do you have proof these buildings are compliant?

Well, two different things

The current metric is basically derived from the EU metrics in the EPBD via SAP and SBEM - ie no more fuel and power than considered reasonable

Proof that the buildings are compliant - none at all, and I suspect many perform far worse than predicted - certainly many of the commercial buildings don't ever perform as predicted. Remember that snake and mongoose issue I mentioned - at design we can massage all sorts of thinks via Level 5 Dynamic simulation - even to the point of reducing air tightness to address overheating risks

However, generally, in the housing sector, that's an enforcement issue rather a need to adopt a new set of requirements

Regards

Barney

Ang on, have I mentally merged PHPP and WUFI, saying that PHPP indicates mould/rot etc? (I've managed without PHPP so far in my career, looking forward to the time when I simply have to use it in full).

I won't be signing. I believe the Building Regulations should be tightened up while retaining the freedom to achieve the required targets in different ways.

There is no way the Government will agree to making _all_ new houses meet the proprietary PassivHaus standard and I think it would be better to tighten up the building regs in general rather than require only a percentage of new houses to meet any particular tighter standard.

Posted By: fostertom

Posted By: CWattersno way the Government will agree to making _all_ new houses meet the proprietary PassivHaus standard

Sure in this England but it's happening in parts of Eire 'or equivalent', and wouldn't be surprised in Wales and Scotland

I have some sympathy with the 'proprietary' description but I think the reason the UK government won't adopt it, or even consider it as an alternative, is that it can equally well be described as 'independent' and in politically-correct terms as 'evidence-based'. The UK building regulations, strategy and tactics has been so thoroughly captured by vested interests that it is unthinkable. Other places are better. The one good feature of UK regulation is that it is requirements-based rather than codified like many continental systems, which allows a great deal of flexibility in some circumstances.

It is the UK government in charge of English regulations. Quite why Scottish and Welsh and Northern Irish MPs have a vote on them, I'm not sure.

edit: oh and there are codified parts of the regs, like water regs GRR and ventilation guide GRR and ...

Is it requirements based? The requirements currently are U values... This seems to me to be the means, not the goal. The requirement should be kWh/m2/time.

I'm pretty shocked how many people seem too think BR++ are enough.

Like many institutions here, it's the whole structure that's wrong.

Posted By: gravelldIs it requirements based? The requirements currently are U values...

There are U-value requirements for individual elements. However, the limiting factor is the overall house emissions as calculated by SAP - if you made all the floors, walls, roofs, windows, doors, etc, to the required U-values the house wouldn't pass. There's an awful lot wrong with the details (IMHO) but that basic approach seems sound to me.

I'm pretty shocked how many people seem too think BR++ are enough.

BRs wouldn't be too bad if they were enforced and if airtightness was a lot better. Just writing down lower U-values in BRs wouldn't solve anything. Similarly, saying things are “Passivhaus” if that's not checked properly wouldn't help much, either.

Posted By: DarylPEd, the values to which you refer are 'backstop' values, maximums allowed. NOT targets!

Agreed. How's that different from what I wrote?

If you build to the 'recipe' or reference values, you will pass.

Which recipe values do you mean? TER, etc? Not AD L1A Table 2 “Limiting Fabric Parameters”, I assume:

Building Regs approved document L1A2.33 Table 2 sets out the limiting standards for the properties of the fabric elements of the building. Each stated value represents the area-weighted average for all elements of that type. In general, to achieve the TER and the TFEE rate, a significantly better fabric performance than that set out in Table 2 is likely to be required.

Eire's close to mandating PH.

God help us then - totally at the mercy of City of London/Wall Street. So much for 'give our country back' - to who?