Embarking on a home renovation is an exciting time. Reconfiguring, extending or simply updating your home can transform your lifestyle, how you use and enjoy your home and how you feel every time you open your front door.
We can’t help but focus on how we’d like our new home to look but what about how comfortable it will be to live in? An energy efficient home is not only essential for comfort and liveability, it will also help with increasingly budget busting energy bills.
By far the cheapest and least disruptive way to incorporate energy efficiency improvements into your existing home is when you are renovating.
These are our top 5 energy efficiency upgrades that we think give renovators the biggest bang for their buck.
1. FILL THE GAPS
In most Australian homes, there are gaps and cracks under skirting boards and around architraves, around doors and windows and between floorboards, not to mention chimneys, ducting, vents and fans that allow air to flow freely into and out of the house. All of these gaps combined can be equivalent to leaving your front door open 24/7!
If you’re after an energy efficient home, start with draught proofing your existing home, block wall vents and look at the options for minimising air leakage through fans, ducts and chimneys.
Also, insist that all gaps in any new additions are sealed. This is simple and cost effective and all good builders should do this as standard practice.
Insulation is essential for a comfortable, quiet and energy efficient home. It acts as a barrier to heat flow so it will help retain heat during winter and keep your home cool in summer.
In an uninsulated home, a significant amount of warmth is lost (in winter) and gained (in summer) through the roof and ceiling. So insulating these areas is an excellent first step. Even if you already have insulation, it may have settled so it is worth checking whether it needs to be topped up.
Move on to the walls. If you are already removing linings or external cladding, this is the perfect time to install wall insulation. If you’re not, look at options for pumping newspaper/wool insulation into the wall cavity, installing an insulated plasterboard system on top of the existing plasterboard or building a new internal wall insulated on the inside.
Finally, the floors. Are you sick of cold air funnelling up into your home during winter through the floor boards? Insulation can be installed on the underside of suspended floors, as long as the sub-floor is easily accessible. If it’s not, you could look at using insulation board under new floor coverings.
But keep in mind that there is a point where adding more insulation isn’t cost efficient – the cost of doing so outweighs any small benefits. Talk to your designer or builder about the optimal levels of insulation for your home. Also, there are different types of insulation available and your designer or builder should be able to advise you on what will work best for you and your home.
When you have decided what insulation to install where, make sure your builder installs it correctly. For example, bulk insulation must be continuous – there shouldn’t be any gaps and it must not be squashed. Losing 5% of the total insulation area of a ceiling effectively halves its performance so it’s crucial that it’s installed correctly.
This is why downlights were previously discouraged. There needed to be a clearance space between the lights and the insulation creating problematic gaps in the continuity of the insulation. However, electrical retail outlets can now supply sealed, heatproof boxes for LED downlights that seal them and allow you to insulate over them.
Select a builder who is happy for you to inspect the insulation before it is no longer accessible and/or who offers to verify that the insulation has been installed correctly by taking images of it with a thermo-imaging camera.
Now that you have an air tight house, you’ll need a good ventilation strategy. Your designer or builder should be able to advise on the various ventilation options available and what would work best for you and your energy efficient home.
3. USE DOUBLE GLAZED WINDOWS & DOORS
Glass is the path of least resistance in the building envelope. Up to 40% of a home’s heating can be lost and 87% of its heat gained through glazing, according to the Australian Government’s Your Home Guide. So, for energy efficiency, appropriate glazing is critical.
Heat and noise easily pass through standard single glazed windows. Upgrading to double glazing dramatically reduces the transmission of both heat and noise, keeping your home quiet and the indoor temperature more stable.
But a window’s effectiveness is not solely down to single versus double glazing. It also depends on design factors, such as the window frame (timber, aluminium or uPVC), size, orientation and shading, and the technical specifications of the glass and any coatings to be applied to the glass (eg low-e glass).
Before you select your windows, check the WERS ratings. The Window Energy Rating Scheme (WERS) rates the energy and energy-related performance of different window units taking into account the frame as well as the glass. It gives stars for heating and cooling performance and a 5 star rating is the maximum.
Selecting the optimal window unit for different locations in your home is a complex process. The important thing is to make sure that your designer and builder appreciate and understand the pros and cons of the various options (in terms of thermal performance) and don’t simply specify windows and doors based on aesthetics and cost.
4. SHADE YOUR WINDOWS & DOORS
Shading glass externally is a very effective way to keep rooms cool in summer and can reduce heat gain by a staggering 70-85%. Including external shading in your renovation design can be an easy and relatively inexpensive step towards achieving an energy efficient home.
Eaves and overhangs work well on north and south facing windows and glass doors as they keep out high summer sun but allow the low winter sun in to warm the home. Other options include fixed or retractable horizontal or angled awnings, pergolas/solar roofs with fixed or adjustable blades and shade sails.
Shutters, awnings, external blinds or vertical shading work best on east and west facing windows and glass doors. Often an adjustable solution is best for these windows and doors as the low angle of the sun makes it difficult to get adequate protection from fixed shading. Also, adjustable shading can be deployed only when needed.
And don’t forget about skylights – these should also be shaded.
There are a wide variety of options for external shading according to taste, budget, functionality, location, desired longevity and environmental credentials. Your designer should be able to help you to select the ideal external shading for your energy efficient home.
5. GO FOR ENERGY EFFICIENT APPLIANCES
Appliances make up around one third of a typical home’s energy bill according to the Australian Government’s Your Home Guide. With highly energy efficient appliances now widely available, choosing more energy efficient options when replacing or upgrading your appliances during a renovation is an easy win.
A range of appliances must now have energy rating labels, including clothes washers and dryers, fridges, TVs and dishwashers. An energy rating label gives a star rating for the appliance and tells you how much electricity it is likely to use each year. The more stars, the more efficient the appliance. So when shopping for new appliances, factor in running costs by comparing the energy rating as well as the purchase price of different products. Also, don’t buy a larger appliance than you need. A larger fridge uses more energy than a smaller fridge with the same energy star rating.
If possible, locate your appliances with energy efficiency in mind. For example, locate appliances that require hot water as close as possible to your hot water service and locate fridges and freezers away from sources of heat and out of direct sunlight.
With so many decisions to make when renovating your home, it’s easy to overlook energy efficiency. But spending time now investigating and researching your options to improve energy efficiency will pay enormous dividends, not only in reduced energy bills but also in achieving a comfortable and healthy home. And you will be helping to reduce our greenhouse gas emissions from energy generation.
Don’t worry, help is out there. Choose a designer and builder who are as committed as you are to achieving an energy efficient home. They will be able to advise you on practical and cost effective energy efficiency options. You could also consider bringing a building sustainability expert on board early in the design process to assess your design iteratively as you settle on the best decisions for your project holistically.
Before you select your builder, make sure they have energy smart credentials and are appropriately qualified and experienced professional builders. To help you do this, we have prepared a FREE guide: The 7 Critical Questions to Ask Before You Choose Your Builder. Download it now to learn:
How to check whether your builder is up to the job
How to avoid getting caught out by builders charging you more than you were expecting
and more handy tips