Architects, designers, builders, here?

[BMWST?]

Like your ideas except not sure about straw bales. Mouses like them. As do insects. As does water...and water always gets in.

I'm merely a layman but always thought 200-300mm wide earth/mud/cement bricks made sense. Still need bracing, and battens for an airgap and external cladding. Double brick with an air space would be fine? Solid.

no..they perform very badly in earthquakes.

[Swoop]

Double glazing is not compulsory and often isn't even required in most areas in NZ (and sometimes even in Invergiggle).
The NZBC H1 Energy Efficiency objectives, performance and functional requirements are based around limiting energy used to heat houses rather than setting minimum insulation requirements. Satisfaction of this objective is frequently demonstrated by the Calculation Method and sometimes by the Modeling Method without use of double glazing. For instance if you triple the insulation value of your walls, floor and roof Or your construction design and materials create sufficient mass as a heat sink and you only have a few small windows your energy consumption is stuff all (which is the NZBC objective). Most people don't understand the Calculation and Modeling Methods so choose to use the Schedule Method which stipulates the minimum R values of insulation to be used in walls, floors, roofs and windows (and these are the requirements that vary between zones) However that is their choice. It isn't mandatory.

True. It does, however, come down to the individual territorial authority and how they interpret the rule. With increased nervousness from councils over liability for approving structures, they will be erring on the side of safety from now on.
The only approved double-glazed window solutions are those that have been fully tested. At the moment only aluminium meets that standard, but a serious attempt is being made by timber windows to comply.
Currently only single-glazed timber windows have been tested under 3619 (1979).
The easiest solution (to get approval) will be to double glaze.

[flyingcrocodile46]

True. It does, however, come down to the individual territorial authority and how they interpret the rule. With increased nervousness from councils over liability for approving structures, they will be erring on the side of safety from now on.
The only approved double-glazed window solutions are those that have been fully tested. At the moment only aluminium meets that standard, but a serious attempt is being made by timber windows to comply.
Currently only single-glazed timber windows have been tested under 3619 (1979).
The easiest solution (to get approval) will be to double glaze.

Timber and UPVC window frames provide superior thermal resistance, (though be sure to research your UPVC options very carefully). however the component that most needs to achieve an insulation value (R Value) is the glass rather than the frame as the frame is a very small area compared to the window.

Appraised double glazed window panels can be retro fitted to most existing windows including timber. There may or may not be any NZ timber joinery manufacturers who have a formally tested whole joinery system (don't know) but it isn't needed.

Here's one company making a nice business out of catering to everyone's irrational lust to have double glazing.
http://www.aucklanddoubleglazing.co.nz/

To give an idea as to the significance of double glazing insulation values as opposed to single glazing, here are the NZBC H1 Acceptable Solution R values for Non-solid construction – minimum R-values for schedule method (Climate Zone 1);
Single Glazed = Min R . 19
Double Glazed = Min R . 26
Roofs/ceilings are =>R 2.9
Walls are =>R 1.9
Floor are =>R 1.3
As you can see, the difference between single and double glazing is only R .07 (2% of the value of roof insulation) So it's all a big deal over fuck all For my money thermal drapes meet my needs fine but that is too easy.

I know TA's are famous for causing problems for designers in respect to acceptance of detailing on matters of compliance but as far as I am aware, most of the reputation isn't justified and is more likely a symptom of insufficiently detailed compliance with the NZBC by people who often don't have a clue about what the requirements actually are. Of course this can be exasperated by individuals at TA's who also don't know up from down.


If anyone needs more info on the issue here are a couple of helpful sites
http://www.branz.co.nz/H1_support
http://www.consumer.org.nz/news/view...double-glazing

[Grumph]

I see straw bale construction mentioned...for what it's worth there's one just down the road from us in Hororata village. built on a poured slab like the two brick and block houses next to it. The straw house slab is in one piece where the neighbours are broken post September. There's some cosmetic cracking of the rendering inside and out which the owners have already fixed themselves.
I speculate that the lighter mass of the straw house has saved the slab...the neighbours are write offs due to the membrane under the slab being torn and water rising inside...

[skinman]

In response to the aerated concrete comment. from what I know of it from Hebel, good R value but not waterproof. Can be used as mid floor in precast units or lower floor on a block foundation wall. Cannot be used as basement walls retaining and must have an exterior cladding. I believe some plaster finishes are acceptable but more research would be needed. I have thought that it could make a good midfloor as it would be quiet and not have the weight of conventional concrete.
Double Glazing
best thing about it is condensation will not form inside which can save having the sill rot out and also not allow mould growth. It also makes for a quiet house. Will cut down road & aircraft noise.

[porky]

Timber and UPVC window frames provide superior thermal resistance, (though be sure to research your UPVC options very carefully). however the component that most needs to achieve an insulation value (R Value) is the glass rather than the frame as the frame is a very small area compared to the window.

Appraised double glazed window panels can be retro fitted to most existing windows including timber. There may or may not be any NZ timber joinery manufacturers who have a formally tested whole joinery system (don't know) but it isn't needed.

Here's one company making a nice business out of catering to everyone's irrational lust to have double glazing.
http://www.aucklanddoubleglazing.co.nz/




To give an idea as to the significance of double glazing insulation values as opposed to single glazing, here are the NZBC H1 Acceptable Solution R values for Non-solid construction – minimum R-values for schedule method (Climate Zone 1);
Single Glazed = Min R . 19
Double Glazed = Min R . 26
Roofs/ceilings are =>R 2.9
Walls are =>R 1.9
Floor are =>R 1.3
As you can see, the difference between single and double glazing is only R .07 (2% of the value of roof insulation) So it's all a big deal over fuck all For my money thermal drapes meet my needs fine but that is too easy.

I know TA's are famous for causing problems for designers in respect to acceptance of detailing on matters of compliance but as far as I am aware, most of the reputation isn't justified and is more likely a symptom of insufficiently detailed compliance with the NZBC by people who often don't have a clue about what the requirements actually are. Of course this can be exasperated by individuals at TA's who also don't know up from down.


If anyone needs more info on the issue here are a couple of helpful sites
http://www.branz.co.nz/H1_support
http://www.consumer.org.nz/news/view...double-glazing

Well said, and 100% correct, but then you knew that because you too have been to school. Thermal bridges and all.

As for the concrete,
Concrete isnt green. In fact it is very grey due to the ingredient called cement that is the most unfriendly of all construction materials manufactured. It has the highest CO2 emmission rate (during the sintering process) and then chuck in the steel smelting and ore extraction.......
Is it a versitile product with some fantastic properties, hell yeah, just not very "green".

Just out of curiosity, have you ever used the modelling method. Seems to be a AS that every one talks about but no one has actually any experience in.

[flyingcrocodile46]

Just out of curiosity, have you ever used the modelling method. Seems to be a AS that every one talks about but no one has actually any experience in.

Seen it twice and struggled to get my head around it fully (wagged school too much) and have far too many more important things to have too absorb. I don't see the consequence of H1 compliance failure as the end of the world and it seldom becomes a matter for litigation.

[Swoop]

UPVC window frames

That is an incredibly small share of the marketplace. A better long-term solution for the homeowner but not the "greenest" process to manufacture.

For my money thermal drapes meet my needs fine but that is too easy.

I have the same solution...
Looking at replacing with DG aluminium though.

[Winston001]

To give an idea as to the significance of double glazing insulation values as opposed to single glazing, here are the NZBC H1 Acceptable Solution R values for Non-solid construction – minimum R-values for schedule method (Climate Zone 1);
Single Glazed = Min R . 19
Double Glazed = Min R . 26
Roofs/ceilings are =>R 2.9
Walls are =>R 1.9
Floor are =>R 1.3
As you can see, the difference between single and double glazing is only R .07 (2% of the value of roof insulation) So it's all a big deal over fuck all For my money thermal drapes meet my needs fine but that is too easy.

Nice post and great information.

Living in the deep south I've long been interested in keeping warm. The sort of R value information you provide has been difficult to find. Nevertheless I'd come to the conclusion that - theoretically - heavy drapes are better than doubleglazing.

So much for theory. I'm fortunate enough to have full doubleglazing and it is a total win. Not only does it keep the house warmer, it also cuts down outside noise remarkably. I know drapes are good (use them as well) but in the daytime you want the light to come in without losing the heat.