Timber vs Steel

For decades, Kiwi homes have predominately been built with timber, and with approx. 40,000 hectares of trees being cut down it’s no surprise that we are now faced with a shortage. But if we are cutting so much down to supply, why is the NZ construction industry burdened? Our offshore trade obligations have certainly impacted our wood manufacturing sector over the last ten years with 60% of logs felled in NZ being shipped offshore, and 50% of total logs cut down in NZ are exported to China.

And it’s not only our trade commitments, but New Zealand needs to build 40,000 new homes to meet the shortfall in market and under the current Labour Government there are plans to build 18,350 public and transitional homes. All this requires more timber, which means supplies tighten, pricing increases and the average cost of building a house or building follows this trend.

So, what is a solution? Steel framing.

Making the switch from timber to steel framing is often a point of contention for builders and homeowners / developers alike. As Kiwis, we may be recognized for our ingenuity, but we are also averse to change, with our “she’ll be right” and “it’s always been done this way” attitude, convincing someone to choose steel frame over timber is often the first battle.

So, let’s look at the differences between timber and steel and why there are many reasons to back steel framing over timber – particularly during a national timber shortage!

1. Construction time decreases (easier to assemble)
2. Lighter than timber (up to 70%)
3. Prefabricated with openings to allow for services without drilling on site (plumbing and electrical)
4. Stronger, more durable, higher resistance, straighter – great for wet locations to avoid needing to dry moisture from studs, supports more weight for longer periods, no warped studs or warping floors, no burrowing of small pests, non-combustible
5. Very little wastage
6. Compatible with roofing and cladding systems
7. External insulation – the only way to build properly with steel studs

As our homes age, maintenance is of course ongoing. And there are differences in certain factors of a timber home vs steel home, which may lead to additional costs down the track. Here are somethings to consider.

Timber: rotting, termite damage, stud damage, mould, natural disaster damage (flooding, earthquake etc) – however easy to add extensions or remove walls etc.

Steel: Insulation costs can be higher, rust (if there are leaks or condensation issues), additional work when adding extensions or new walls – however generally a lower cost in insurance fees (in some areas).

With both options there are pros and cons and typically in NZ it has come down to the builder’s choice on what material they are most comfortable with (“it’s how we’ve always done it” decision), but this is a decision that should be discussed with the client as ultimately, they will be responsible for any additional costs down the track.

So, while New Zealand is facing a timber shortage it doesn’t mean the building industry has to suffer – by diversifying the way that we build, we can ease the effects of shortages of specific materials.

It’s our security both financially and having a roof over our head.