Don’t pay to heat and cool the outdoors

Typical homes have so many leaks in places homeowners would never imagine.  Air escapes through gaps all over the building envelope, causing a slow leak almost all the time.  No matter if its winter or summer, homeowners need to be educated so we quit paying to heat and cool the outdoors.   According to a survey by the North American Insulation Manufacturers Association (NAIMA), 90% of existing U.S. homes are under-insulated.  That’s a whole lot of wasted dollars and energy flying out those sneaky leaks.  Even new homes fall into this category all the time.  New construction should be the perfect time to build a structure that doesn’t have hidden leaks – and wasted heating and cooling costs.

Ensuring a strong thermal envelope around a house is the number one way to increase energy efficiency in a home and reduce the excessive heat gain during the summer and heat loss in the winter.  Enter Structural Insulated Panels, SIPs.  A SIP building envelope has an extremely high whole wall R-Value and low levels of air infiltration, reducing the overall loads for heating or air conditioning equipment in the home.  According to Oakridge National Lab, our 6″ SIP is 58% more energy-efficient than normal 2×6 framing with R-19 insulation and 15 times tighter.

Air Transfer

Air leaks through joints in sheathing and the inevitable gaps between lumber connections and between wood framing and the insulation.  SIPs dramatically reduce air transfer within walls and roofs by minimizing these joints and by providing solid, continuous insulation across each panel’s height, width and depth.

SIPs can be manufactured up to 8′ x 24′ without joints in the OSB, whereas traditional stick-framed sheathing is typically on 4′ wide.  Air can also leak through electrical and plumbing holes that are drilled in lumber studs.  Where in SIPs these channels are built in and not exposed to elements every 4′.

The airtightness of a SIPs home has been repeatedly confirmed with blower door tests.  Many stick framed and batt insulated roofs allow excessive air transfer walls where not just through gaps in construction materials, but also through insulation and wood framing materials.  This requires more AC or Heat to keep a home comfortable.  A SIP panel is solid, and doesn’t have these same cavities throughout roof, wall and floor panels.  In fact, SIPs are so superior in keeping the heat inside in the winter (or the cool air inside in the summer), that Energy Star does not require a blower door test for SIPs homes to earn the Energy Star rating.

Convective Looping
As warm air rises and cold air sinks in a conventionally framed wall cavity, a  natural phenomenon called thermal or invective looping occurs, wasting valuable energy.  Unless the insulation is a solid material to stop this air movement, it doesn’t matter what the insulation’s R-Value is.  What good in insulation if heat-carrying air can flow though it and the cavities of the wall?  SIPs’ solid insulation core helps eliminate this.

Thermal bridging occurs where there is a continuous element (such as studs within traditionally framed walls, and studs within traditionally framed walls, and stud-to-siding connections) between he cold and warm faces of a wall.  These wood elements form a bridge between the inside and outside that can allow heat or cold to pass through by conduction.  Simply installing R-19 batt insulation in a stick wall doesn’t mean the whole wall will have a R-19 R-value because there is still a significant amount of thermal bridging in traditionally framed stick walls.

Stick-framed buildings rely on lumber at regular intervals to provide structural support.  15-25% of the shell of a stick-framed home is lumber, compared to as little as 3% in the shell of a typical SIP framed home.

SAVE ENERGY & IMPROVE INTERIOR COMFORT

As the science above explains, not only does SIPs help control energy efficiency in a home, a SIP constructed home reduces air movement and drafts; reduces moisture; reduces noise and reduces dust and allergens from penetrating and circulating through living spaces.  A SIP home can also be constructed faster and with less labor because the insulation, framing and sheathing are combined into one panel.  When comparing stick framing with SIPs framing, there really is no question on the best choice.   See examples/photos of what SIP homes have been constructed around the country.