Does 'green building' pay back?

Solar power, double glazing and other 'eco-build' options worth it? Photo / Getty Images

There was a time when solar panels only went on spaceships. Then the homes of the rich and guilty.

These days a lot of "green" or "eco" building options are well within budget — but nearly all represent a higher up-front cost. So are they worth it?

The experts say it pays to plan ahead and consider cost benefits beyond the dollar sign.

First, it's worth remembering that, before considering larger investments, you can save a lot of money with a bit of self-discipline. We should all be turning stuff off we aren't using, keeping showers short and selecting off-peak times for energy-hungry processes such as washing if we want to save the dollars.

At the next level it's a no-brainer to make simple efficiency changes such as switching out old-fashioned fluorescent lights with LEDs and using low-flow taps and shower heads, now all standard on new builds, anyway.

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In addition, many aspects of creating an environmentally conscious home are just good design. They shouldn't add to the costs. These include fundamentals such as proper ventilation and aligning the home with the sun.

They also mean attending to details such as ensuring there is a covered space outside for drying clothes and keeping carpet out of entry areas to prevent damp. Getting these right can make the difference between an unpleasant property and a pleasant one.

Government subsidies have helped make floor and ceiling insulation the norm.

Inexpensive heat pumps can provide the basis of almost any high-efficiency heating system you care to choose.

But what about big ticket items such as extra insulation levels over and above Building Code? High performing "low-e" windows, heat pump, hot water cylinders or electricity generating solar photovoltaic systems?

The first thing to consider is your plans for the home. You might be willing to wait a while for payback if you are planning to raise a family in the house for the next 20 years. The same could be true if it's the retirement home you don't plan on leaving – or you might simply want to live in a house that expresses these values, even if you have to pay a little more for the privilege.

But if you are going to sell within the payback time, you are reliant on buyers valuing double glazing and solar the same way you do. The expansion of the HomeStar energy efficiency ratings across the sector makes this more likely but many buyers still won't factor the real value of your upgrades into their offers.

Alex Reiche, director of the Building Excellence Group, specialises in high-efficiency building design and assessment and says: "In building a new home, there are a number of options that provide tangible cost benefits up to a certain point," he explains. "After that you may be over-capitalising on your property.

"The way to think about it is to do things in sequence. Once you have all the basic design elements right you can look at fittings like insulation, showers, hot water cylinders, which have a direct correlation to your energy bills.

"Good solar design and insulation reduces the amount of energy required for space heating so you can go for smaller and more cost-effective heat pump options. This in turn informs the adequate size of solar system for your home, which will then pay back within a reasonable period."

Beyond that there are undeniable health and peace of mind benefits in using "eco-friendly" non-toxic materials and less impactful methods of building. Selecting those means putting other elements in your cost/benefit analysis than simple dollar signs.

Reiche adds: "It's worth considering that, if like most people, you have the combined cost of energy plus mortgage interest payments, then you might find some options provide instantaneous payback. For example, if paying $15,000 for an upgrade that puts your mortgage payments up by $20 a week, but reduces your energy bill by $25 a week, you are getting an instant benefit of $5 a week."

Getting the performance v budget balance right can take a bit of expertise, so it's also well worth putting the money aside for some expert advice before you make the big decisions.

• By Andy Kenworthy, Sustainable Business Network