With Sustainable House Day fast approaching (Sunday, September 16th) I thought it would be interesting to talk to Carolyn and Garth about their post-war home and how they have made it more energy efficient and sustainable, as well as their open house on Sustainable House Day.

Sustainable House Day is an annual event run by Renew where the public has access to sustainable homes across the country. These homes can be new builds, renovations, or ongoing improvements.

Hi Carolyn and Garth, thank you for taking the time to talk to Secret Design Studio about the work you have completed on your post-war home today.

I know that many people who live in similar mid-century and post-war homes have concerns about their energy usage, and would be interested to understand the changes that you have made to your home.

Q1) How long have you lived here, why did you buy this home, and what condition was it in when you purchased it?

Carolyn, Garth and their cat Magpie in their warm and comfortable post-war home which is one of the homes open for visiting on Sustainable House Day (September 16th) for people who have pre-registered on the Sustainable House Day website

A1) While we weren’t looking specifically for something mid-century or post-war, many homes from this period were better designed than their earlier counterparts, thanks to the Small Homes Service. Air conditioning was still uncommon, so people still built in cross-ventilation, eaves, and other passive home features to keep their houses thermally comfortable.

We bought our home 4 years ago. It met our wish list of access to public transport, good solar orientation, and space for growing fruit trees, vegetables, and chickens. It was previously a rental and was in need of TLC: mould and water damage in the bathroom, leaky gutters, an internal door being used as an external door.

Carolyn and Garth’s home which is modest in size compared to the McMansions that are popular today is typical of many that were built in the post-war years. This photo was taken before the solar panels were installed.

There had also been some unsympathetic renovations in the wet areas (bathroom, laundry, toilet, and kitchen). But the foundations were sound and the layout worked. We moved in as soon as we removed the ugly floating floorboards, and sanded and sealed the original hardwood floors underneath.

Carolyn and Garth’s home before and after photos. The first photo is from the real estate listing from 2014, and the second is from 2018. Only the eagle-eyed will notice the addition of the solar panels on the roof.

Q2) From when you purchased it you have worked to make it more environmentally friendly. Do either of you have a background in the science behind this or is it something that you have researched as you have gone along?

A2) Neither of us has a background in the industry. I work in healthcare and Garth is in IT. We became interested in sustainable design by attending various Sustainable House Days.

Q3) How much has your external energy supply reduced? How much electricity do you pay for in winter?

A3) Grid draw has reduced to less than 20% of pre-renovation consumption. Our average grid consumption throughout 2017 was 1.71kWh per day. Some significant changes have been made during 2018, including the installation of underfloor insulation which is having a noticeable impact and our consumption should drop further. In 2017, we averaged 3.25kWh per day during the winter months (June-August). This effectively cost us nothing as we drew down on credit accrued during the summer months from our solar panels. We paid nothing out of our own pockets and still had credit at the end of August.

Carolyn and Garth’s simple roof with its good orientation was ideal for a bank of 32 solar panels.

Q4) Should people think about payback of their solar panels and house batteries, or just do it as it is the right thing for the environment?

A4) Payback is certainly a consideration but everyone is different. People need to make investment decisions according to their own financial/social/environmental concerns and priorities.

For us, we had the financial capacity to invest in an oversized solar array and batteries. We invested in batteries because 85% of our usage was after dusk and this technology allowed us to use the power generated by the solar panels in the evening, during our peak consumption period.

Our decision meant that despite our electricity consumption doubling (because we moved from a gas-and-electric home to an all-electric home) we will achieve a return on our investment in around 7-8 years instead of 13-14 years. In other words, despite the high cost of batteries, we do achieve a return on our investment over the system’s expected lifespan.

The benefits to the environment (clean energy for us and the grid) are an added bonus.

New electrical switchboard and a bank of five batteries under the house were part of the electrical upgrades required to take advantage of the new solar panels.

Q5) Do you have any regrets in disconnecting your gas supply? Do you ever miss it?

A5) The biggest change for us is the stovetop. You can’t do cooking that requires an open flame on an induction stovetop (i.e. grilling capsicums). But the glass surface is much easier to clean and it’s easier to cook things that require low-heat.

Otherwise, we don’t miss gas at all.

A new kitchen replaced the tired 1980’s kitchen which was not original to the house. All of the appliances, including the electric cooktop, were selected for energy efficiency. No gas appliances were installed in the new kitchen. Splashback tiles were new/old stock.

Q6) What are the three biggest lessons that you have learnt in this renovation? What advice would you give to anybody else who has a similar 1960’s brick veneer home who would like to live in a more environmentally responsible manner?

A6) Friends and family keep on commenting on how much bigger everything feels, but the home’s footprint has not increased. Bigger isn’t always better. Clever design should give you better use of space and make a room or house appear more generous than it is. And getting the most out of the space you’ve got is important because bigger builds lead to a greater drain on money and resources, both upfront and ongoing.

New energy efficient kitchen looking towards the dining area.

You may also want to extend the lifespan of your renovation. Avoid adopting the latest trends because they won’t be on-trend forever and you (or someone else) will end up with the 10-year renovation itch. Plus avoid stopgap measures that require rectification a few years down the track. Constantly renovating is not sustainable: it uses up valuable resources and creates more wase.

Instead, if you have a Mid-Century Modern or Mid-Century Modest home, embrace the style. It’s already dated so there’s no fear of it becoming even more so. Do your research; get some expert help. There’s a growing interest in homes from the 50s, 60s, and 70s, and people will appreciate a sympathetic renovation done well. Plus, every original feature you keep is one less item ending up in a landfill.

New laundry fit-out with energy efficient washer.

And one more thing: plan for flexibility. Life isn’t static; your needs and your family’s needs will change in the years to come. Make sure that your home can keep up with these changes.

Q7) What have been the biggest surprises, and have there been any disappointments? Would you do anything differently if you were starting again?

A7) For our sustainable home-improvements, we sometimes had to choose between conservation and performance. For instance, retrofitted double-glazing is most effective when the whole window is replaced. We chose to keep the wooden frames, an original feature of our home, and only replace the glass with double-glazed IGUs. Also, by keeping the original spouts in the bathroom, we’ve had to sacrifice on water-efficiency.

Magpie the cat observing the old windows before the double-glazing retrofit, and the same window after the double glazing retrofit.

Old bathroom with original fittings and new bathroom re-using many of the original fittings in a sympathetic manner to the original house.

One thing we may have done differently would be to insulate the walls before we moved in. We could have gutted the house, removed all of the plaster, and put in insulation and put up new plaster and painted. It would have delayed our moving in quite a bit but we didn’t know then what we know now. We’ll chalk this up as a learning experience.

Newly insulated roof space

Q8) What resources, such as magazines, books or websites would you recommend for anybody who would like to follow your example?

A8) There’s a government publication called Your Home. The Alternative Technology Association (ATA) also publish Sanctuary and Renew, magazines focused on sustainable homes and technologies, and run events such as Speed-Date a Sustainability Expert, as well as Sustainable House Day.

ReNew: technology for a sustainable future is Australia’s premier magazine on practical sustainable living

Carolyn’s article for ReNew magazine about retrofitting double glazed windows. Issue 143 can be downloaded from the ReNew website for $5.00.

We also enjoy following the My Efficient Electric Home group’s discussions on Facebook. It’s a good place to get ideas and contribute information about successes and experiences.

Q9) Is your work finished here, or do you have another project planned, or in the planning stages?

A9) We’ve been neglecting the garden of late, so we’ll probably start working towards becoming more self-sufficient with our fruit and veg. And we need to get the house electric-vehicle ready.

Q10) Sustainable House Day is coming up on Sunday, September 16^th. What is Sustainable House Day?

A10) It’s an annual event run by the Alternative Technology Association where the public has access to sustainable homes across the country. These homes can be new builds, renovations, or ongoing improvements, but they all must have at least four sustainable features.

Some of the other houses that are open to pre-registered people on Sustainable House Day on Sunday September 16th 2018 that are in Victoria.

Q11) In 2017 there were over 200 homes across Australia open to the public on Sustainable House Day, will 2018 be the first year for your home to be open? What could a visitor to your home expect to see?

A11) We first opened our home in 2017. Over 150 people visited us which we thought was a great outcome for our first opening. We had representatives from the companies that installed our solar panels and batteries (GreenSky) and our double-glazing (Thermawood) and the feedback was good that people were able to talk to these experts on the day.

We plan to run a similar format this year. We are hoping that in addition to GreenSky and Thermawood, we will also have a representative from the lead contractor who performed the recent kitchen, bathroom, and laundry renovations.

Generally, members of the public get to see what a lived-in sustainable home looks like. With our home, they will get to look at features such as low-VOC finishes, sustainable technologies (batteries, heat-pumps), retrofitted double-glazing, and insulation. They can ask the whys, whats and hows for each feature. Since we’re not part of or affiliated with anyone in the industry, we’ll give them our own honest opinion.

Q12) How did you become involved with Sustainable House Day?

A12) We started off as members of the public wanting a bit of a sticky beak! Since then, we’ve gone from casual onlookers to hosts; we’ve learnt so much over the years and thought it would be nice to pass this knowledge on to others and help them make their own sustainable-home journey.

About Sustainable House Day link: https://sustainablehouseday.com/about-shd/

Q13) Visitors need to register for Sustainable House Day, how does that happen?

A13) Yes. Only people who register will have access to the addresses of the homes open on Sustainable House Day. Please sign up and favourite the homes you want to visit as it gives each homeowner an idea of how many people are turning up on the day!

Sustainable House Day Registration link: https://sustainablehouseday.com/subscriber-registration/

Thank you so much for your time, and being happy to share your knowledge. Best of luck with your open house for Sustainable House Day 2018.

Carolyn and Garth’s living and dining area in their all-electric home is easier to heat and keep cool than living areas in today’s McMansions as it is modestly scaled by comparison, with no two storey void spaces.

I had the pleasure of first meeting Carolyn and Garth as they were clients of Secret Design Studio’s “Dr Retro House Call” service where I helped them with their kitchen and bathroom renovations. Feel free to visit our verified reviews from previous clients on the Houzz website:

Dr Retro House Calls review link