Structural Insulated Panels

Bright Build is one of the few New Zealand building professionals experienced with Structural Insulated Panels (SIPs), and we are so impressed we built our home and workshop in Wellington using the Formance SIP Panel system.  Read on to find out why Craig, as an experienced Registered Master Builder, chose this product for his own home…

Structural Insulated Panels (SIPs) are a highly thermally efficient system made from composite timber panels either side of a thick polystyrene core – just like an icecream sandwich.  SIPs create a highly insulated envelope that significantly reduces (and in some cases, eliminates) the need for heating in winter, and keeps cooler in summer.

The entire building envelope – external walls, ceilings and floors can be created using Structural Insulated Panels (SIPs).   Joins between panels and for joinery (such as windows and doors) are foamed, taped and sealed, to create a practically airtight interior. 

The external window and door joinery also has to be highly insulated to enable the high performance envelope to function.  Triple-glazed timber joinery is considered the gold standard, and Thermal-Heart joinery combined with Low-E glass and argon gas is also very good.

Due to the airtight nature of the building, an airflow system is used to bring fresh air in and remove stale air.  Tailor-made for Wellington conditions – fresh air is brought in without opening windows and inviting the chaos of gale-force wind.  Also weeded out in the ventilation process are environmental allergens and airborne pollutants.  And with no airspaces in the wall, there is no internal condensation or annoying draughts.  In case you are wondering, you won’t suffocate in a power cut – if the power is off for a while simply opening a window or door will do the trick. 

The SIPs panels are designed around your plans (or for the most economic option, it is possible to design your project to the panel dimensions).  The panels are pre-fabricated off-site and shipped to your site, where they are fast to assemble and make the project watertight in a much shorter timeframe.  Due to the precise nature of SIPs production, it is even possible to pre-order your windows and have them installed as soon as the walls are up.

Cost-wise the Formance SIPs panels can work out slightly more expensive upfront than traditional framing.  Below are some of the reasons Formance consider this an investment:

• Reduced energy bills.  One of the biggest benefits of building with SIPs is reduced energy bills. Formance SIPs help contribute to a high-performance house, meaning it takes less energy to heat and stays warm for longer. This will result in real savings on electricity each month. 
• Faster build process. Time is money. By getting your home built faster and with less stress, you can move in sooner and start enjoying your investment. 
• Potentially greater resale value. Overseas studies have shown that high performance houses can have up to 8% higher resale value than the norm. Real estate experts here have indicated to us that this trend is likely to carry through to New Zealand as well.
• Strength. SIPs are incredibly strong, providing double bracing capability to the wall. Our SIPs also have a high level of impact resistance, as well as resisting post-build structure degradation. This means less future repairs for you, and greater savings in the long run. 
• Comfort. It’s hard to put a dollar figure on comfort, but the value of being happy, healthy and comfortabl­e in your own home is worth a great deal. 

The payback period can be very short given ongoing reduced energy use on heating and cooling.  And the cost of energy is always increasing.

SIPs are strong and stable – another bonus for Wellington buildings that require large amounts of bracing with our wind and propensity for earthquakes.  The two key attributes of Formance SIPs in earthquakes are their strength and ductility (meaning that they can not only withstand the applied force of an earthquake but are also able to take some shock out of the movement by allowing some non-permanent flex in the structure).   It’s no secret that many high-end homes being built in post-earthquake Christchurch are using Formance SIPs due to their superior performance in ground shaking.

In New Zealand to date, the standard build method has been insulation fluff (e.g. Pink Batts) stuffed into framing.  In the image about  you can see the heat loss of traditional building (shown as the red glow), compared to a SIPs home.

New Zealand has been lagging the rest of the world in utilising SIPs.   Europe, UK, North America, Japan and other countries have been using them for over 40 years to create healthier, warmer, cheaper homes.   SIPs homes are tried and tested, and even known to create a premium when sold due to their enhanced qualities.  For some boroughs in Germany, this type of building is now the minimum building code. 

SIPs are a major component of Passive Homes – to find out more, click here.

Want to find out more? Contact us.