Change in any industry can feel sluggish when you have a great idea you want to see catch on. That is certainly true for proponents of structural insulated panels or SIPs for short. In the 1930s, Frank Lloyd Wright experimented with an early prototype that lacked insulation, in his search for materials that were functional, stylish and affordable. The lack of insulation was a problem that Aldon B. Dow went on to tackle. As a student of Wright’s, he identified the inherent flaw of the panels as not being energy-efficient. He overcame that problem in 1950 and is credited with creating the first SIP.
But what are SIPs made of and what do SIPs look like? They are a composite structure, made up of three elements:
- Foam core made from expanded polystyrene, extruded polystyrene or polyurethane (EPS, XPS or PU)
- Structural facing (usually a 7/16″ Exposure 1-rated, oriented strand board)
- Structural adhesive (unless using PU)
SIPs are manufactured to strict specifications, and they can be fabricated to fit nearly any building design. The are extremely cost-effective, energy-efficient and strong. They arrive, already insulated and clad, as complete wall units.
Using SIPs can reduce the cost of labor (up to 60% compared to traditional stick frame construction), and the green aspects of SIPs are a clear selling point. They create less waste, are 65% more energy-efficient and reduce the cost of HVAC (heating, ventilation, air conditioning) by an average of 50%. The LEED Certification for stick frame averages a 2, while SIPs have a much higher certification of 42.
So why isn’t every builder using SIPs in home construction today?
According to Scott Berkun, author of eight books, including How Design Makes The World, he states in a blog post, “The default state of a new idea is non-adoption. Most new ideas go nowhere. Most ideas travel slowly, if at all …”
The story of SIPs certainly proves his point. Invented for use in 1950, they are still fighting to gain real ground in the single-family building arena. One challenge? Contractors who have always built with stick-and-frame construction may be slow to change what’s been working for them for years. Addded to that, the initial pricing of SIPs may have discouraged some from seeing them as a viable alternative to traditional construction methods and materials. With today’s building material costs, the price point for SIPs has dipped below traditional stick framing methods.
Lindsay Moon, of Searchlight Lending is a licensed mortgage broker with a background in the construction industry. She’s knowledgeable about SIP’s build better aspects, especially as they relate to the accessory dwelling unit (ADU) market and affordable housing options. She’s active on several affordable housing coalitions and advises ADU start-ups in Marin and the San Francisco Bay Area.
Moon works with new contractors all the time who are starting to do projects using SIPs. She says, “It’s so simple to learn to work with them, and we do provide some training. They can even watch a YouTube video. It is important to note that if you want to build using SIPs, you have to start at the very get go. You have to be designing that way.”
Moon also works with architects and contractors. She’s happiest when they are all familiar with how easy it is to work with SIPs. She adds, “Sometimes it is just a matter of familiarity. Creativity is not limited by SIPs. They are really great for ADUs, too.”
When working with an architect, Moon indicates that the initial process is much like it would be for conventional construction. The architect generates their architectural set of plans, and they can either bring in their own structural engineer or work with one recommended to them. All the other steps leading up to refining the design and the permitting process are much the same.
When building a house with SIPs, once the design is finalized and the permits approved, the contractor will prep the site, start on the groundwork and dig the foundation. Meanwhile, the panels are being put together in the factory and cut to size according to plan. Once they are ready, they’ll be trucked in and offloaded.
Moon adds, “If space is limited on your job site, you can have the panels trucked to your contractor’s site, if they have the space to store them. Then they can bring the panels as needed. Once the foundation is ready, you can see your structure take place within a short time. It is amazingly fast, especially when compared to traditional building methods. Because it takes less time, it costs less, too. You are building faster, greener and the walls are much straighter, making it easier to hang sheetrock. Also, the chase for the wiring is already installed at the factory. The SIPs I represent meet and exceed all California building codes, which are stricter than most states. And new restrictions are coming down the pipeline for both the commercial and residential building codes.”
If you are considering how to make your dream home a reality, or add an ADU, and want to learn more about green building materials, make an appointment today. We’d love to explore your project options with you.