How fast you can grow a house?
Tuesday, 12th Jul 2022
We were recently asked how long it would take for Australia’s plantation estate to grow the amount of structural timber needed to build the average house frame.
Firstly, it’s important to note this question was particularly timely, because Forest & Wood Products Australia (FWPA) / (our parent company) has just released a report on timber usage in residential construction.
The aim of this report was to develop meaningful data by analysing a sample pool of nearly 20,000 residential building plans from the 2017–18 period in New South Wales, Queensland and Victoria.
Ultimately, the report found the weighted average amount of structural timber required for the construction of an Australian house frame was 14m3.
Beyond this, FWPA undertook a survey to gather additional data from a wide range of Australian softwood forest growers to accurately calculate how long it would take to grow that amount of timber.
This survey collected and aggregated responses to quantify Australia’s:
- estate average growth rates (cubic metres/hectare/year, or Mean Annual Increment – MAI)
- total stocked area (hectares)
- percentage of standing log volume suitable for structural sawn timber processing (sawlogs)
- percentage of mill recovery of structural timber from structural sawlogs.
While survey respondents accounted for over 75 per cent of Australia’s softwood estate, the aggregate data was extrapolated to ensure it covered the actual total area of softwood plantation in a way that accounted for areas impacted by recent bushfire events.
The results showed area-weighted MAI from respondents was 20. Of approximately 900,000 hectares, around 19 per cent of standing volume is processed into structural timber at end of rotation.
FWPA used these inputs to calculate the time taken for Australia's plantations to grow structural timber for the average house frame, and the answer we came up with is around 140 seconds.
Research has shown that consumers remember certain numbers more than others, which is why in the upcoming consumer campaign for The Ultimate Renewable™ you’ll notice we are using 150 seconds rather than 140.
So there you have it! When using timber, the average Australian house frame can be ‘grown’ in about two-and-a-half minutes. The industry should be proud that one more house frame has been grown during the time it took you to read this short article.