Prefabricated 170x35mm Treated pine wall frames at Floreat Haus 2
Choosing the right materials is an important part of every house design, but even more so for a high performance Passive House. Your framing, which provides the structure for your entire home, is especially important. This doesn’t mean you always need the newest, flashy material brought to market, though. Instead, we can look to the ever-reliable timber. It’s been used for a very long time, and for good reason.
Sustainable and durable
As a natural material, responsibly sourced timber is one of the most sustainable materials available in the building industry. It’s renewable, recyclable and has a much lower embodied energy (the energy used to manufacture a product) than alternatives like steel and concrete. On top of this, trees naturally absorb carbon dioxide (CO2) during their life, and most of it will remain in the timber after it’s cut. This means that while other framing materials will release CO2 into the atmosphere during production, timber actually absorbs it as it grows.
There are many different types of timber, but with the right selection it’s a very durable material. Care needs to be taken to ensure the timber is protected from termites and the weather, but when done right it can last a long time. Many timber framed houses in Australia are well over 100 years old, and still going strong.
Natural insulation
As an organic material, timber has lots of tiny air pockets that act as a barrier against heat and cold, making it a natural insulator. This natural insulation makes it a great way to reduce thermal bridging in your construction. Thermal bridges allow heat to travel in or out of a building and occurs when a building material, such as a window frame, has a higher conductivity than the materials around it. Since the framing makes up to 10% of the outside surface area of your home, it’s important to use a product that has low thermal conductivity. When compared to steel framing, a timber framed home will have far less heat loss from thermal bridging. This can significantly reduce costs on heating and cooling your home.
Reusability
When demolishing a house, if care is taken to ensure it stays in good condition, timber can be reused in another home. To ensure it stays in suitable condition it’s taken from the original structure to a company that trims and re-treats it. It can then be re-sold as recycled timber.
Recycled timber is appealing to many buyers as it’s stronger than new timber. This all has to do with moisture content, as the drier a timber is the stronger it is. New timber is placed in a drying kiln to remove the moisture, but with limited time they can’t remove all of it. Recycled timber, on the other hand, has had many years to dry out and will have essentially no moisture content. This means that it prevents mould growth and is an even better natural insulator than new timber
Lightweight
While the strength to weight ratio varies depending on the type of timber, it’s consistently been found to be a very strong, lightweight option. When compared to steel, the strength to weight ratio of Radiata Pine is 20% higher. Lighter materials take less energy to transport, meaning timber is much more efficient than other structural materials.
Being so lightweight timber is also fast to erect and modify on site, which will save you both time and money.
Suitable for prefabrication
Timber is suitable for prefabricated framing—when the framing is planned, assembled and built off-site in a factory. There are many benefits to prefab framing that will save you both time and money. The most significant being affordability. As the frame is built in a factory there’s much less wasted materials, and manufacturers will give you an accurate quote prior to starting, rather than working to an hourly rate like most carpenters. Further saving money, prefab frames take much less time. As they’re built in a controlled environment that’s protected from the weather, they can be completed much faster, and built ahead of time to be finished right when you need it. The controlled environment also allows for careful reviews of plans that ensure your frames are built to exact specifications with good craftsmanship throughout. Finally, prefab framing is a more eco-friendly option. Any timber left-over from a frame can be reused directly by the manufacturer rather than being transported off-site or sent to landfill.
Commonly used
Timber framing is well understood by the many qualified carpenters in the local industry. Not only will it be relatively easy to find a carpenter in the first place, but you’ll also be able to get competitive quotes. The same may not be said of more niche eco-building products.
Building a home can be an overwhelming process, and the many materials you’ll need to choose from doesn’t make it easier. If you’ve decided to use timber framing, for example, you then need to decide what size and type of timber to use. Leanhaus can help you make these decisions, and you can always be sure that we’re considering sustainable options wherever possible.