If you think about it, the traditional way of building is just that. Traditional. Whacking up some timber framing, cladding the exterior then protecting it with a roof has been how Kiwis have built houses for decades.
Sure, different products are now used and insulation and other technology has helped with the heating, soundproofing and performance of a home. But the construction methodology is virtually the same and there are still a lot of inefficiencies, despite the advances society has made over the same period.
I apologise if I'm offending anyone. I'm simply trying to paint a picture of why Kylie and I began exploring different building methods for our dream home. In fact from the moment we set foot on our section, we wanted to investigate prefabricating our house.
The initial driver was trying to be as light on the section as possible to maintain its natural beauty. So the idea of building off-site, then plonking it down in a completed state met that objective.
After talking with our builders it was clear it would be impossible to get fully built structures down our driveway and into position. But they thoroughly endorsed the idea of prefabrication, bringing to our attention the substantial time savings it would provide by eliminating delays due to the weather, and as a result, reduce costs considerably.
So another two reasons joined the list. Prefabrication would be faster and cheaper. The main question then became if we can't do it in full sections, how could we do it? Our builders provided a possible solution and off to Christchurch we went to investigate Method Building Systems and its prefabricated panels.
It was a frosty winter's morning when we arrived at Method's office near Christchurch Airport. General Manager Nick Hubbard met us at the door and immediately treated us to some typical southern hospitality as he gave us the 101 on its Formance SIP panel system over savouries and coffee.
Kylie with one of the Formance SIPs.
The Formance SIPs.
As Nick explained, Method manufactures Structurally Insulated Panels (SIPs) that are used as walls, roofs and ceilings to construct any house design imaginable. This all happens in a factory where they are precision cut before being transported to site and erected like a giant set of Lego. In a single day.
Say what? Walls up within a day! Now that got our attention. But it was only the beginning to a day of discovery, eventually making us wonder why you'd ever consider building any other way.
Think of SIPs like a giant sandwich. In the middle is an expanded polystyrene core which has strand board structurally laminated to either side of it, creating an incredibly high performing building panel. By connecting a series of these together, they do away with the traditional framing and batt insulation approach.
The benefits of building with SIPs became increasingly clearer the more Nick revealed to us. While building with SIPs may cost up to 5 per cent more than using timber framing, they reduce total build costs due to the time saved on site. But the savings don't stop there; they can reduce energy costs by 50 per cent, too.
As we discovered, in a traditionally framed house, gaps are often left around the batts, plus they'll naturally sag over time, significantly reducing their effectiveness. Even a 4mm air gap can decrease insulation performance by up to 15 per cent and a 16mm gap will reduce it by a whopping 35 per cent.
Nick Hubbard, general manager of Method Building Systems.
SIPs form a perfectly airtight structure, creating a beautifully efficient home that will be performing just as well in 50 years as it was on day one. Not only would that mean our home would be extremely pleasant to live in, we'd also get the benefit of cheaper power bills.
Then we discovered how strong they are, able to brace the house too. Among other things, this meant we wouldn't need steel portal frames in our living area to support the large 6m spans, ensuring perfectly flush walls and uninterrupted windows.
As we flew home over the Canterbury Plains, the decision to work with Method and its Formance SIP panel system was a no-brainer. We'd have a faster, stronger, cheaper and warmer home. Plus we'd be one of the first in New Zealand to build this way - which seemed a fitting status for our unique home.
• Find out more about Ben and Kylie's dream home at ourdreamhome.co.nz
• For more information on the Kiwibank First Home Buyer's Guide visit: kiwibank.co.nz and search for "first home".