Tips on maximising energy efficiency in Canberra

Hi all, I'm about to go into a meeting with my builder (McDonald Jones Homes) for colour selection. I've bought a westward facing block, and looking to build a double story place.

Would appreciate any tips on how to maximize the energy efficiency (NatHERS) rating of the new home within those parameters. Anything from best roof and brick colours for for the area, what to do with windows/eaves, etc. As well as any other tips you may have.

One thing thing to add, the build is in Denman Prospect (climate zone 24).

Get as much (and the highest rated) insulation you can afford. Walls, ceiling, sarking etc. Consider other insulation like slab-edge, under slab, garage, internal walls.

Light coloured roof (reflects) will perform better than a dark coloured one (absorbs).

Alot of the efficiency will already be decided by the orientation of your house on the block - see https://www.yourhome.gov.au/passive-design/orientation as well as by the size and position of windows. Go double-glazed windows for increased performance. Consider outdoor blinds/awnings for problem windows.

Window treatments (curtains/drapes/blinds) can also make a difference to energy usage - basically the heavier the material the better its thermal performance e.g. blockout curtains.

Air-tightness is vital for energy efficiency and we are garbage at this in Australia - make sure windows and doors are properly sealed, check all caulking around architraves and doorframes. Avoid cavity sliding doors. If you wanna go nuts you can get a blower door test done once built to really see how leaky the house is. We spend so much money heating and cooling air that just escapes.

Ceiling fans everywhere.

Solar panels.

Lighting - reduce the number of ceiling penetrations where possible to allow for continuous ceiling insulation - consider alternatives to having 400 downlights.

Not everything will affect the official NatHERS rating but will make a difference to your overall energy costs. Best of luck!

Insulation, insulation, insulation.
Windows are a huge portion of the energy efficiency recipe and unfortunately you are restricted with which windows you can choose with this particular builder as would be the case with many other volume builders.
Window sizes may be restrictive so focus on sashes instead. Opt for awning or casement if possible but casement are usually quite pricey in a double glazed unit so awnings may be your best bet.
Ceiling fans are an easy add-on accessory.
Remove overheads above the fridge, opt for full electric, ie no gas appliances. Heat pump hot water, induction hot plate. Surface mount LED lights. Interlocked wet room exhaust fans.
Consider raising window sills on the East and west elevations and add eaves on north elevations.
If it’s two stores add as much floor insulation as yiu can afford.
Slab insulation won’t be an option but you’ll be on waffle pods so that’s a good start.
Curtains, flooring and light roof color will help keep the house cool.
And if yiu can, avoid bricks. Cladding or even hebel if you must have a solid exterior.
And appropriately size the ac. Don’t accept their default package. It may be oversized.

hi bimbob. I know this is an old post, but im deciding whether or not to use slab insulation for a home with hydronic heating in Melbourne.

Are you suggesting that a waffle pod slab will do part of the job? is it worth 10K to also do slab insulation?

Thanks in advance!

Hi there.


Slab insulation is a MUST with in floor heating to achieve the best results.

Waffle pods help but its not a part of the solution for in-floor heating.

Not using slab insulation with in-floor heating is like having triple glazed windows without wall insulation.
Slab insulation is a MUST with in floor heating.

Waffle pods help but its not a complete solution.

Not using slab insulation with in-floor heating is like having triple glazed windows without wall insulation.

I know someone in the Adelaide Hills (similar to Melb climate) who only has waffle pods and no slab edge insulation. Their hydronic still works well, but I'm sure it would be more efficient with slab edge insulation and perhaps better under slab insulation. How much more efficient I don't know. Might not be worth the extra cost. I think in Melbourne it's recommended to get slab edge insulation anyway regardless off having hydronic.

I'm not that pro hydronic anyway. It's pretty laggy so you don't get a quick injection of heat/coolth when you need it. It also uses a lot more power (than RCAC) so if you need to use it out of solar hours it costs more (or uses a lot of battery energy). It's a luxury imo so if you have the money then go for it.