A pine in the butt
Timber, it's a hot commodity at the moment. You have more chance of watching Carlton win than being able to get your hands on it!! For decades timber has been the bones of our house and it's the major material that we use in Australia for residential construction. At the moment there is a huge timber shortage in the country and it’s causing some problems for many builders. For years we could just call up and put in our order, but now we face a lead time of more than eight weeks. It’s forcing us to be extremely organised, however, it does create some problems along the way.
Several reasons are causing this shortage.
Increased demand due to low mortgage rates allowing people to borrow and build.
A post-Covid boom in the construction industry placing more demand on the need for timber.
Government stimulus packages promoting residential construction.
In recent times the closure of our domestic sawmills - we now import over 80% of our timber.
Covid meant that many of the international sawmills shut down and were unable to produce timber for an extended period.
It's frustrating but it's not the end of the world. It just means being patient and also being well organised. Timber prices have increased dramatically and we probably won't see a drop in prices in the near future as this short supply is expected to last at least another six months. Having said that, it doesn't mean you should be rushing to ditch your timber frame at your current or future build.
There are a few alternatives to the traditional timber frame. I think we should start with the most common and well-known alternative... steel frames.
Recently you may have seen these on "the Block" and I saw another local builder advertising that they were moving to steel frames. Steel frames whilst may sound strong and sturdy can create a huge range of issues in the future.
This builder claimed they are "prioritising sustainability" and moving from using timber frames to steel frames for "sustainability reasons". Now I'm not looking to pick a fight here, but I feel that is greenwashing. If they said they were doing this as timber is becoming too expensive I would understand that. Just to make people aware if they are considering using steel frames, you should know that when comparing steel to timber
Steel is not a renewable material
Steel production is one of the highest polluters on the planet leaving a huge carbon footprint. Depending on what you read, around 7.2% of the total global emissions are from manufacturing iron and steel. [1]
Steel releases 1.9 tonnes of CO2 into the atmosphere. Timber will absorb 1.7 tones of CO2. This statistic was directly from the World Steel Organisation. [2]
It contributes to thermal bridging in a home, making your home extremely uncomfortable to live in. All that energy that is absorbed by the steel frame will be transferred into the house and will make it near impossible to heat and cool. This will cause your energy bills to skyrocket in an attempt to keep your home at a stable and comfortable temperature. Just picture a metal spoon left in a pot on the stove. Except the stove is the sun and your home's steel frame is the spoon. This is becoming such a problem in steel-framed homes that the Building Codes Australia will add in a section relating to thermal bridging next year.
Since we have an issue with condensation in our frames, water is sitting on the steel. Steel is a highly corrosive material that will only negatively impact the structure of the steel framing.
Timber has 4 times the thermal resistance when compared to steel
It's advertised as 100% recyclable however to recycle steel you still need to use virgin steel and iron ore to create the recycled steel. Recycled steel is 55% more efficient than creating new steel, but it's still worse than timber!!
These are just the basic issues with steel, and I'm sure you can find more. When I did even more research to check this out, the only sites that would claim this was more sustainable was the steel suppliers and fabricators themselves. I don't have a problem with people using steel frames, but please don't advertise it for sustainable reasons - it's misleading, irresponsible and greenwashing!
So what should you do?
Now I know this timber supply issue creates a problem for most builders, but it also creates opportunities. There are other construction methods used overseas that may be able to be fast-tracked and reduce our reliance on conventional timber frames.
The framing method you should be looking into is SIPS (structural insulated panel systems). Think of these as an insulation sandwich. On the outer layers you have some OSB plywood and between that some Expanded Polystyrene foam (EPS). This structural element can act as your floor, roof and walls and can see a home go from no frame to fully completed within a few days. This is due to it being lightweight and easy to handle. This is an eco-friendly way of building as it requires little energy to create and can provide you with a high amount of insulation in a confined space (108mm wall will provide you with R4.2, or 161mm wall R6.7). This system also provides an easy way to achieve airtightness in our homes. It’s used throughout Canada and is already becoming in demand in Australia. EPS foam does have its issues as it does not break down and is not biodegradable, however it can be recycled without a loss in performance. In the coming year, this is what I will be constructing my home out of.
It's about time we started to think differently about buildings in Australia. This presents a chance to provide alternatives to timber framing that will help lead the way to a higher standard of construction. By thinking differently, we should be able to build homes that can perform just as well as timber and also stand the test of time.
If you would like to learn more or are interested in building a Passive House or high-performance home please reach out. We’d love to hear from you!
[1] - 1 - https://ourworldindata.org/emissions-by-sector
[2] - https://www.worldsteel.org/en/dam/jcr:c3acc5fd-e3c2-458c-a2cc-8c4880b9334c/Steel%2527s+contribution+to+a+low+carbon+future.pdf