SIPs: The Innovative Panels Supporting Sustainable Prefab Homes

More and more New Zealanders are recognising the benefits of sustainable houses. That means the design elements that make them so effective are becoming more popular as well.
 
One such design element is SIPs, an innovative way to build the floor, roof, and walls of a home in a way that minimises both labour costs and build times and maximises energy efficiency. To learn more about SIPs and how they can be used as a vital element within a high-performance home, read on.
 
What are SIPs? 
SIPs, or Structural Insulated Panels, are high-performance, thermally efficient composite panels, in which an insulating layer of polystyrene is sandwiched between two layers of structural strand board. This alternative build material offers a new way to construct the building envelope—walls, roof, and floors—for residential and commercial buildings.

Our SIPs are made and cut by Formance in Christchurch, and Craft Homes is one of only four preferred installers in Auckland.

• Learn more about Formance SIPs.

The Difference Between SIPs and Stick Framing
Traditionally, homes have long been built with stick framing, or frame and truss, but SIPs offer major advantages in a range of important categories, including:

1. On-site build times and labour costs. SIPs are prefabricated, cut to specifications at the factory and delivered to the site ready for construction. Sticks, however, are delivered to the site as timber frames and roof trusses and must then be assembled. That’s why SIPs significantly cut down on on-site build times compared to standard construction techniques, offering savings in labour costs, and reducing the risk of a building site delay.
2. Precision and durability. Stick framing is more labour intensive because it takes longer to get every angle and measurement precisely right. What’s more, many pieces of frame timber don’t arrive perfectly straight. SIPs however are precision-cut, and their layered structure provides a double bracing that inhibits bowing. With fewer joined pieces, they will also last longer and are less prone to creaking and noise.
3. Resale value. Homes built with SIPs tend to enjoy higher resale values, because of their contribution to the home’s enhanced energy efficiency and durability.
4. Materials Costs. SIPs may cost a little more upfront, but as is the case with many other elements of passive homes, cost less over the full life cycle of your home once you factor in labour and energy savings.
5. Availability. SIPs are more readily available at the moment, with Formance panels having a confirmed supply chain well in to 2022 , as New Zealand faces a shortage of materials for framing. Frames and trusses can be harder to get your hands on during a timber shortage like the one we have now, which could further widen the difference in build times between the two options as well.

 
The role SIPs play in prefabricated homes
Energy efficiency is where SIPs really shine. Stick framing doesn’t offer insulation for the building; insulation must be added—and the building envelope made airtight—after the frame is constructed, but SIPs are solid panels with built-in insulation. SIPs have no gaps in their insulation, and offer much superior air tightness compared with stick framing, with up to 90% less air leakage than standard frames.

Because they’re cut to spec at the factory and delivered to the site ready for installation, SIPs also cut down on the amount of construction material waste a building produces. Additionally, they can be custom-made for the climate you live in, incorporating various thicknesses and types of foam based on average temperature and humidity levels.

• Read our Guide to Prefabricated Builds and Prefab Homes.

Work with a preferred SIPs installer for your new build home
Craft Homes is one of New Zealand’s very few passive house builders with experience and expertise in SIPs. We’ll work with you to ensure that every element of your new home is built to peak performance. Contact Craft Homes today to book your free consultation.