A builder breaks down the four most cost-effective upgrades for an energy-efficient home: thicker walls (140 mm) to hold better insulation, higher R-value insulation (R4 walls, R6 ceilings), double-glazed windows with PVC frames, and careful installation. Everything else is secondary.
The 4 things that give you the best bang for your buck when building an energy-efficient custom home. Building an energy-efficient custom home requires literally tons of building materials and hundreds of individual steps in design and construction, but not all are of equal importance. True to Pareto's 80/20 rule, a small number of things contribute more significantly to the end result than other things. In this article, you'll learn about the most important aspects of an energy-efficient custom home, so you can prioritize your spending for the best outcome. If I was building a home for myself, here's where I would spend my money. Walls. Standard house walls in Australia are 90 millimeters. We recommend thicker 140 millimeter walls that have more room for insulation. The better you insulate your home, the more stable the internal temperature will remain, no matter what's happening with the weather outside. In my book, this is top priority because once your home is built, you cannot change the width of your walls. Insulation. Insulation is rated according to R-value. This is a measure of the insulation's resistance to heat flow. It's thermal resistance. A higher R-value indicates the insulation will be more effective in slowing heat transfer in and out of your home. Standard wall insulation in Australia is R2.5. Thicker walls allow you to use R4 insulation, which provides almost double the insulating protection in winter and summer. We also recommend R6 insulation for ceilings. The small extra cost for this higher performing insulation is only a couple of thousand dollars across your entire house. This will quickly pay for itself in comfort and energy savings. Doors and windows. Apart from not having enough insulation, nothing compromises the energy stability of a house more than doors and windows. Firstly, due to poor seals that allow airflow when the doors and windows shut, and secondly, due to thermal bridges where heat transfers through the glass and casings of the doors and windows. Double glazing will stop heat transfer through the glass, and new PVC frames rather than aluminium that is highly conductive will minimize heat transfer through the casing of the doors and windows. Care and attention. The very best building materials will only work as well as they are installed. R-6 insulation that is installed carelessly will allow heat transfer through gaps. Windows and doors that are installed inaccurately will allow air to flow through gaps around the casings. Be sure to choose a builder who takes time to seal all the gaps so the building products you're paying for have the chance to give you the result they were designed for. There are many other things I could mention, including mechanical heat recovery ventilation, and if you're looking to build a truly Passive House, This is a must. But if you're looking for the best bang for your buck, start with the things listed above. That's where I would spend my money. For more information about how to get best bang for your buck when building an energy-efficient custom home, we invite you to book a free consultation where we will answer your questions and show you the most efficient and affordable ways to get a healthy, comfortable custom home You will love forever.
