Eco-Panels vs. Stick Built Construction

The method of stick-built construction that is prevalent today has changed very little from what was used in the early 1800’s.  When it was first developed in the 1830’s lumber was plentiful and the need for a safe and well insulated building envelope was not recognized as it is today.

Eco-Panels allows you to build a stronger, safer, more comfortable and significantly more energy efficient structure while helping to conserve our natural resources.


Eco-Panels consist of a core of dense polyurethane foam – the same type used in many of the most advanced refrigerators and coolers manufactured today – sandwiched between two layers of siding material.  Together this essentially forms an I-beam, with the foam as the web and the siding as the flange.  I-beams have long been know to be significantly stronger than traditional dimensional beams (graphic of I-Beam compared to Eco-Panels).

Eco-Panels have been independently tested by the civil engineering school at the University of North Carolina in Charlotte.  The test results indicate our product is significantly stronger than traditional stick-built construction – so much so that we can typically offer a 4:1 safety margin – 33% greater than the standard 3:1 safety margin of stick-built construction.

The California residential building code requires the periodic presence of a “shear wall” to provide additional protection against seismic activity.  Often built by nailing plywood or OSB to the face of a stud wall, this structure of this special wall prevents the wall from collapsing “accordion-like” on itself.  A house constructed of Eco-Panels is essentially a “shear house”, with joining walls supporting each other from collapsing in a method much stronger than stick-construction.  Homes constructed of structural panels have long been shown to better survive a seismic or wind (hurricane) event  due to the improved strength of the structure.

Eco-Panels offers a single piece corner panel molded in our factory.  The corner joint of a wall can be a wall’s weakest link and with a single molded corner joining two walls we have entirely eliminated that juncture.


A typical stick-built house consists of a series of wall cavities one after the other – a cavity of standard insulation (whether fiberglass, open-cell spray foam or similar) that will literally form a “chimney” in the event of a fire.  Standard insulation is quickly consumed by a fire leaving a long vertical cavity of oxygen.  Like turning a burning match upside down the flames will have no resistance while burning up the wooden studs to the ceiling.  In a stick-built house you are essentially living in a series of chimneys.

Fire needs three things to keep it going – oxygen, heat and fuel.  Remove any one of these things and you eliminate the fire.  The polyurethane foam in an Eco-Panels panel is a thermoset material.  It does not melt or vaporize like an open-cell spray foam or polystyrene insulation and therefore no oxygen is allowed to enter the wall cavity.  As burn tests show (SIP Burn Test video link) fully exposed foam does not conduct heat and after an initial flash chars over – charred foam does not promote flame by itself.

And as noted in the “Stronger” section above, when it comes to the structure of a home stronger is safer.  With the ability to better survive external forces like extreme wind or seismic activity with its I-beam structure and molded corners, coupled with an inherent resistance to the “chimney effect”, an Eco-Panels building is a significantly safer structure than one built by traditional means.

More Comfortable

ASHRAE – the American Society for Heating, Refrigeration and Air-Conditioning Engineers – notes that the most significant factor for influencing a person’s comfort inside of a home is radiant energy.  Radiant energy is the energy – heat or cold – that we feel coming off of an object.  We all know what it means to stand next to a “cold wall” and even a 2x6 stick-built wall filled with open cell spray foam insulation will feel cool to the touch on a cold winter’s day.  That same wall filled with a closed cell polyurethane foam insulation and no studs (thermal breaks) like Eco-Panels will have several times the insulating efficiency of a traditional stick wall and the temperature of the inside surface of the wall will feel like the temperature of the inside air – not the outside air.

3-5 Times More Energy Efficient

An Eco-Panels wall system uses closed cell polyurethane foam injected into an open cavity during the manufacturing process.  This foam expands at incredible pressures and is contained during the curing process by very large steel presses.  Every possible space in this panel is filled to a high density, entirely surrounding outlets, window and door framing, etc.  The foam is rated at about R7 per inch, and when considering the standard OSB siding (although other sidings are available) we rate a 4.5” panel at R26 and a 6.5” panel at R40.  There is no vertical stud in this panel that would wick thermal energy from the exterior to the interior – the combination of the sidings and the foam forming an I-beam are already stronger than the traditional stick-built wall.  A stick built house, on the other hand, typically anticipates a framing factory (amount of wood in the envelope) of 25-27% - so let’s call it 26%.  That means that on average 26% of the building envelope is wood of R value 1 per inch.  Typical fiberglass insulation averages an R value of 3.2 per inch and we will assume for the sake of this exercise – and it’s not always true – that the other 74% of the wall has the R3.5 material.  Taking a weighted average of these two numbers tells us that the building envelope has an effective insulation rating of R2.6 per inch.  For a standard 2x4 wall stud dimension (3.5” thick) that equates to an R value of 9, or approximately 1/3 of the R26 value in our 4.5” panel product.  For a standard 2x6 wall dimension (5.5” thick) you would have an effective insulation rating of about R14 compared to R40 for our 6.5” panel product. 

It’s easy to value energy efficiency and now more important than ever.  In the first two months of 2008 alone natural gas prices have risen 26% on average nationwide.  But how do you value comfort, strength and overall safety for you and your family?  With an Eco-Panels system we can give you all of this at once, offering you perhaps that most elusive of cost metrics, peace of mind.