This is a Guest Post from Dan Sheehan, owner of DS Construction in Lake Tahoe California. Sheehan has a B.A. in Economics (energy and environmental) and B.S. in Geography from CSU. He is constantly looking for ways to lessen the impact that construction has on energy, resources and the environment. You can follow Sheehan’s sustainable building methods on his blog.
Building for the environment
There are many ways a home can be classified as “green”. However, no matter what, it all comes down to energy. Energy is used to create a resource, shipping, heating as well as cooling a home and building a home. The most important thing to remember is that no tangible resource is unlimited thus remains that we should respect and use those resources responsibly. I will be addressing a form of green building which conserves energy by using methods in my building practices as a general contractor in Lake Tahoe, CA.
What are Structurally Insulated Panels (SIPs)
Structurally Insulated Panels (SIPs) are composite panels made up of a rigid polymer foam core with a sheet of OSB (oriented strand board) on either side. SIPs has many uses including: floors, walls and roofs. They come in a variety of sizes and thicknesses.
Many wall panels are 4 inches thick; however we have personally used SIPs that were 6.5” thick due to the climate and snow loads in Lake Tahoe. The panels have a very high strength to weight ratio and have proven to be ideal in natural disaster areas such as along the Gulf Coast.
Why build with SIPs
SIP homes are extremely energy-efficient due to their high R value which is a measure of thermal resistance. The higher value of R is better. SIP homes also include tight envelope and minimization of thermal bridging. The walls of conventional wood framed homes are relatively inefficient.
The insulation between the framing or “studs” keeps a conventional home insulated. However, that insulations effectiveness are typically compromised with poor installation practices. Studs, themselves, produce very poor insulation, have low “R” values and heat is transferred or “bridged” through the wood. The SIP panels are virtually solid foam which has a very high “R” value thus there is little opportunity for thermal bridging and heat loss.
By reducing a home’s heating and cooling requirements; green builders are reducing the use of valuable and limited fossil fuels and other resources while at the same time reducing our contribution to global warming. Since the panels are light, shipping them requires less in fuel and transportation costs.
As far as installation and labor cost’s go; the house we built was completed within 6 months from foundation to finish. The roof went on in 1 day! This also means lower labor cost’s.
This is part one of Building with SIP series. Green Building Elements will continue to look at SIP homes tomorrow with Dan Sheehan’s 2nd post.
Photo Source: Dan Sheehan