Wall insulation

Improving my house’s heating and cooling and energy efficiency is an ongoing project.

This week it was wall insulation.

Obviously this is best fitted when the house is built, but in a house built circa 1930, the only way is to retrofit it.

They do this by drilling small holes in the walls all the way around the house, then spraying in filler stuff into the wall cavity.

Insulation installation

They’ve filled the holes, but they’ll need sanding and painting, which leaves me somewhat regretting I didn’t do this before I got the house painted in 2015. Not to worry, but for now the house looks like it has measles.

Last year’s winter gas bill (covering 15th June to 15th August) was a whopper, at $489 ($7.87 / 354 MJ of gas per day) – similar to 2016. (In 2017 we were away on holiday for some of winter.)

I’m hoping that by getting the new insulation in time for winter, the gas bill for winter this year can be reduced quite a bit – hopefully daytime warmth can be better retained into the evening and overnight.

It might be a while before the investment (not insubstantial) pays off, but already there’s a noticeable difference, which is good.

Future options around the house include:

  • double-glazing on the windows
  • under-floor insulation
  • PV panels for the roof
  • replacing gas cooking with electric
  • replacing gas central heating with more reverse cycle units
  • and one I learnt about recently which seems like an easy no-brainer: a balloon in the fireplace.

Decarbonising my home

While my most pressing home renovation need is the bathroom (planning to do this the next time my sons are away on a trip), I was also thinking:

Governments should be doing a lot more on climate change, but what are the major emissions in my home, and how could I decarbonise?

The car. I recently bought a petrol car, because given how little I drive, I couldn’t justify the cost of hybrid or electric, and with brown coal power generation, electric cars arguably just move emissions from the tailpipe to elsewhere. Hopefully by the time this car is replaced, most electricity (certainly in my house) will be green and electric vehicles will be more affordable. So let’s leave the car aside just for the moment.

In the house itself, several of the appliances involved are quite old and inefficient, and may need replacing anyway in coming years. So there’s an opportunity to move away from gas (unavoidably fossil fuel) to electricity (which can be renewable).

Gas central heating — this system is more than 20 years old, and not very efficient by modern standards. Maintenance also seems to be increasing.

Current thinking seems to be that split system air-conditioners are more efficient than has central heating, particularly from electricity from renewable sources.

There’s a cost there of course — each area of the house would need a new unit fitted. I got one for the main living area a year ago for cooling, which is the other obvious benefit of installing them.

Good insulation also helps. I’ve done the roof, and we have external blinds for summer, as well as ceiling fans, but wall insulation is worth doing too.

My ancient stove

Gas cooking — my ancient gas cooker still works around 90 years after it was installed. It’s got minor problems though with gas leakage, and both the oven and cooktop are small and lack precision. We’ve learnt to live with this, but modern facilities would be nice – for instance an oven that’s big enough to cook multiple pizzas.

Replacing these with electric could be the way to go. Electric cooktops can be induction or ceramic — I like the sound of induction, though that may require replacing some of my cookware.

Gas water heaterten years ago I got solar hot water with a gas booster. It’s worked well, though a bloke who came recently to clean the panel mentioned that parts are likely to need replacing before too long — perhaps in the next five years.

Options might include a conventional electric hot water heater (expensive to run) or a heat pump, which can be expensive to install (up to about $3000), but are apparently quite cheap to run. Though come to think about it, I think I paid about $4000 for the solar hot water system.

Solar panels on a roof in Bentleigh

Electricity — currently I pay for green power, but an obvious upgrade would be to invest in PV panels, which have dropped in price markedly, and the new subsidies make it more affordable, even if the feedback tariff isn’t very high anymore.

One benefit of removing the solar hot water would be making more space on my relatively small roof for more PV panels. Some owners of houses with a small roof have been quite creative about maximising the number of panels – see photo above.

There are also different options for PV panels, which some expensive ones generate more power — and of course one can install batteries to make use of the power generated rather than feeding it back into the grid (typically during the day) and having to buy it back at peak times (typically in the evenings). Batteries are really expensive though, well over $10,000 it seems.

Can rooftop solar generate enough power at the hottest part of the day to run air-conditioning?

I also need to keep in mind future development around me. My neighbours on the western side have rebuilt their house as two storeys, reducing sun onto the roof in the afternoon. If the same happened on the eastern side I wouldn’t be surprised — there’s been a lot of similar development in my street.

Put all these things together, and (for a cost) I could move off gas completely, and move most of my power generation to solar, cutting my household emissions to hopefully near zero.

I’m sure I’m not the only one pondering these issues. What are other people doing?

Houses in Campbell St, Bentleigh

What is a “family-friendly” house?

When you’re house-hunting, there’s a continuum of numerous factors weighed against each other, including indoor space, outdoor space, location, walkability, and plenty more, including of course price.

By walkability, I mean the walking distance to amenity such as parks, good public transport, shops. (Walkscore attempts to measure this.)

From some points of view, perhaps the traditional position is that growing families will prioritise indoor and outdoor space over other factors. Big house, big garden.

I didn’t prioritise those when I bought my house; within my budget, I prioritised location and walkability over space. This had both pros and cons of course.

I wanted to flag one of the big advantages.

When I moved, my sons were 7 and 10. Now they’re 19 and 22. Location and walking access to shops and trains (under 10 minutes away) has been absolutely crucial to them gaining a sense of independence through their high school and university years and beyond.

Public transport problems notwithstanding, they’ve been able to get themselves around relatively easily, and enjoy it too, without a long walk or a long wait for a bus to get home — either of which would push them quickly towards driving.

Just for now, my sons are holding off learning to drive, but will do it eventually. With my concerned parent hat on, the risks of personal safety issues while out walking and using public transport are far less than the risks of driving. (The equation might be different if they weren’t both boys.)

Philip Street, Bentleigh (near Patterson Road)

I hadn’t really thought about how this had played out until my sister mentioned pondering moving her family from Moorabbin (under 15 minutes walk from a station) out to “where you can get more house for your money”.

It made me think that teenagers’ mobility is an important issue. You don’t want them being driven everywhere, and neither will they. You do want them to have access to friends, jobs, events and education independent of their parents.

Lack of space has obvious disadvantages. My front and back gardens are pretty, but not big enough for playing footy or cricket or other such activities. More private open space would be great.

But we have a park down the road, and being on a quiet street, we’ve been able to use that space for outdoor activities.

More indoor space would be possible by renovating, expanding upwards, but the budget hasn’t really allowed for that.

When it comes down to it, we sacrificed private space for the ability to get around without driving — for both my sons, and also for me.

Beyond their independence, being able to leave the car at home most of the time is also good for the health and finances of all of us.

It also means they have access to opportunities without the cost burden of owning their own cars.

I’m not alone in going down this path. With pressures on real estate prices, others are raising families in smaller houses or flats / apartments.

Whether it be buying or renting, we all make our choices. Hopefully those choices take everything into account — including things that may not be immediately obvious.

I’m not trying to tell anybody what’s better for their family, but if I had my time again, I don’t think I’d change a thing.

I finally got air-con

(To just see transport-related blog posts, you can use this link — which is also on the top navigation menu)

For years I’ve resisted air-conditioning at home.

Partly it was the cost, partly it was that I really wanted to pursue passive cooling as much as I could — measures that used little or no energy.

To that end, three rooms have ceiling fans, three more have standing fans. The three rooms with the biggest windows have external blinds.

And there’s insulation in the roof. (I haven’t yet explored options for wall insulation or double-glazing, which I suppose I should, especially given it’s a weatherboard house.)

All this helps the house stay cool… to an extent. It’s much cooler than outside on the really hot days, and much better than it used to be, but it still gets up to an uncomfortable 30ish degrees indoors on 35+ days.

This summer I’ve decided to bite the bullet and get an air-conditioner, which will cool the livingroom and adjacent areas.

Split system air-conditioner

Part of what got me over the line was that I finally found an air-conditioning company willing to publish useful information for prospective buyers, rather than making you ring them up and have the sales pitch blasted at you. Thanks Current Force Electrics.

For ages I’d been looking for a rough indication of how much it might cost, and no other company’s web site publishes that type of information. It’s like window shopping but there’s no prices in the window. I don’t know about you, but it puts me off.

Current Force also have useful information helping you work out capacity you need for a particular space, and they clearly explain some of the types of installations, with regard to positioning the outdoor unit. They also do quotes by email, by getting you to send in photos of the space.

I’ve ended up with a 5 KW (cooling) / 6 KW (heating) Fujitsu model, which should be plenty of power for the space, given the other measures already in place.

They installed it on Thursday. It took about 90 minutes. Since then, the weather has been cool, but it’s expected to reach 36 degrees on Wednesday, so air-conditioning will make a big difference to the indoor temperature — and to my power bills, no doubt.

A future house upgrade might be solar power to help offset the additional power, if I can figure out where on my smallish roof it should go.

I’d also potentially consider smaller air-conditioner units in the bedrooms.

My sense is the fans are usually adequate at night — in fact I’m going to get the ceiling fan from the livingroom moved into a bedroom.

But one argument for fitting out the bedrooms with split system units that can both cool and heat is to phase-out use of my old gas central heating in the winter — doing this job with green power (preferably roof-top solar) instead of gas is more energy efficient and environmentally-friendly, and quite possibly cheaper as well.

And if overall temperatures keep rising, it’s probably inevitable that passive cooling just won’t cut it anymore.

How do I pay the electrician?

A couple of years ago I got a ceiling fan fitted in the kitchen.

The electrician was pleasant, competent, and did a good job.

He said he’d send me an invoice. He never did. A couple of months later I emailed him and asked him to send it. He acknowledged the email and said he’d send it. He never did.

A couple of weeks ago I got a ceiling fan fitting in one of the bedrooms.

The electrician was pleasant, competent, and did a good job.

He said his boss would send me an invoice. He hasn’t so far. A week ago I emailed him and asked him to send it. No response.

I don’t seem to have this problem with other tradies. Plumbers and painters seem only too keen to bill me.

I want to pay for the work they did.

Some questions spring to mind:

How do electricians stay in business if they’re so disorganised?

Is it just me?

When do my obligations cease? How many times do I have to remind them to take my money?

Update: I realised the second electrician sent me a quote before the work commenced, which included bank deposit details. It’s not an invoice, but if I don’t get an invoice, I can just pay that amount.

Update 2: He rang me and said he’d been on holiday, but would be sending an invoice. Either that or he reads my blog…