As many people may already know SIPs are made up of two basic components, a rigid foam core and a skin, that are adhered together to form one strong wall system. To help create a greater understanding of what to expect when purchasing an Earthcore SIP we have decided to post several articles explaining the properties our SIPs components. This article will concentrate on the “skins” of the SIPs and attempt to answer most of the common questions surrounding this product..

Earthcore primarily uses oriented strand board (OSB) for it’s skins. Depending upon the engineering requirements of a project and whether the panel is being used as a wall panel or a roof panel, Earthcore will typically supply panels with either 7/16″ or 15/32″ thick skins.

OSB was introduced in 1978 and since that time has been accepted as a common building material throughout the world. “OSB sheathing panels can be used to create horizontal diaphragms and shearwalls in order to brace buildings for wind and seismic loads.”(OSB Guide™) This part of the OSB adds to the overall strength of our SIPs. In the future we will discuss how the strength of the OSB and the foam come together to form a super strong wall. “The ASCE Standard ASCE 16 “LRFD Design of Engineered Wood Construction” is referenced in the model U.S. building codes.” (OSB Guide™)

Frequently, questions as to the environmentally friendliness of OSB arise. What type of wood is used in OSB?, Does OSB off gas?, What type of adhesives are used?

“OSB panels can be manufactured from a wide range of fast-growing species and from relatively small trees. The production process utilizes a maximum amount of wood fiber from each tree that is harvested, and because the process is very highly automated the yield of finished product is very high.” (APA) New growth trees, managed forests, a highly efficient manufacturing process and a long life cycle make OSB one of the more sustainable products on the market. This coupled with  far less embodied energy to create than either steel or concrete make OSB the preferable building product to use.

Off gassing in OSB is not significant, either naturally or from the adhesives that are used to bond the stands of wood together. TECO, a testing facility dedicated to testing wood and building products issued a report in May of 2009 concerning the specifics of formaldehyde off gassing in OSB. This report also explains the type of adhesives used in OSB.

One final issue that I would like to refer to, is our specific supply of OSB. Currently we obtain our OSB from within a 500 mile radius of our manufacturing facilities and the OSB itself is manufactured within that 500 mile radius as well.

Earthcore SIPs strives to be the most environmentally responsible SIP manufacturer it can. Using OSB is just one part of  this mission. Our next topic will discuss Earthcore’s foam and its properties.