Owner build a solar passive house

I designed and Owner built a solar passive house in the Southern Flinders Ranges.
Winter is now nearly here. This will be my first winter with the house 100% complete.
So far my solar passive design in working really well.
The days here are characterised by clear sunny days and cold nights. Occasionally a storm passes through but clears after a couple of days.
So far the coldest my house has got down to overnight is 17 degrees and that is without any form of heating and with minimum overnight temperatures of around 0 to 3 degrees. Typically the house is back up to 20 degrees within a couple of hours after sunrise.
Has any one else designed and built a solar passive house and can comment on its effectiveness?

We are building a solar passive house at the moment. It was designed by our architect. I am surprised that even with nothing but a thin layer of thermal-break insulation on the walls how comfortable it felt in the mornings. As of today we now have insulation in and gyproc on the walls, and with sub-zero overnight temperatures I'll be interested to see in the next few days how it feels first thing in the morning. Heating during the day is no issue, as almost our entire northern wall is glass.

What thermal break insulation and what cladding did you use?

The thermal break insulation is Thermalbrane 6.5 and the weatherproof layer is thin Colorbond steel sheeting.

I can see why you'd want a thermal break.

With brick or most other cladding I doubt a thermal break would help very much.

The cladding is not the issue as it has a R3.4 batt behind it. The issue was isolating steel framing that was the thickness of the wall, so could transfer temperatures from outside to inside. Problem all solved now though.

How thick are the batts to achieve R3.4?

Sorry, got that wrong: R2.5.

R3.4 is the in series addition of plasterboard, insulation, thermal break layer and timber cladding over the Colorbond sheeting.

Probably the most efficient insulation would be dual side reflective PIRFORMATHERM or Kingspan insulation boards installed to the outside of the frame with reflective air space to the both sides (min 25 mm air gap). The bulk insulation in frames is far from being perfect - it is not covering the full surface of the wall, so it is never 2.5 at the studs.

Also, sometimes builders compact the insulation and therefore deteriorate its properties even further.

True, but there is no space for an insulated board. In truth, it's all pretty academic, as most of the north side of the house is glass, which is fairly efficient, but thermally leaky when compared to any of our walls.

Yep, harder to fit in the boards after, makes sense to design thicker wall initially.
Is the glass double glazed?

Yes, it is double glazed, thermally broken, argon filled, low-e glass. Schüco frames and Viridian Lightbridge glass.

Does it make much sense to have Low-E for the northern windows (e.g. in comparison to western)?

Probably Low-E facing inwards to stop radiation from the inside?

On my build I wanted to capture as much heat as possible from the north so I used standard glazing on the north facing windows. My eaves overhand was calculated to the millimeter so I get full shade in summer. Also I had a modest budget for my build so I looked for simple, low cost solutions.

Exactly.

We tried to do the same, but it is not exact. While you can decide to have no sun from the beginning of summer and start getting sun at the end of summer, there are days during the "shoulder" periods where you might want sun when it is excluded and vice versa.

Yeah, & because of the earth's thermal mass, & consequently thermal lag, the seasons lag behind the path of the sun. The winter solstice isn't the coldest time of the year, & the autumnal equinox is warmer than the spring equinox. So it's much more pleasant having the sun through the windows in September than in March, even though the sun is in the same point in the sky.

This sounds like a really interesting notion to read up more on. I've not heard of solar passive houses until now and I’m really eager to hear more about what the users have to say about them. As always, when it comes to real-to-life plans, the whole feasibility has to be well tested before you can really decide whether it's applicable in your life or not. Seems like you all have found good solutions to ensure that every possibility will be able to be taken care of though! AS always, looking forward to updates and more news!

Here's a really good resource.

http://www.yourhome.gov.au/passive-design

Passive design principles are not new, they're just not often applied. It's a pity really, as it can make homes more comfortable and cheaper to run.

I'm at the design stage of a new house in SE QLD on the coast. Currently we use the A/C for ~3 months, and have not needed any heating during the winter months. Some days we even find that the northern sun during winter provides too much warmth. How should I plan for eaves and size windows for the house?

Are there any guides as to when to have no direct sun on the glazing? eg. between 10am-2pm, from mid Nov-Mar.

I'm also debating whether or not achieving passive house standard is worth it.