Residential Applications

The problems


These are a few of thermal, moisture and air quality problems facing builders today in this northern climate.

As new home designs increase in complexity arctic builders are facing some very real problems in attaining an airtight structure. New homes are no longer the simple boxes that they were formerly. Cathedral ceilings and multi-faceted roof lines are becoming much more in demand. The old methods of putting fiberglass in the exterior and trying to do a perfect job of sealing plastic over it are becoming difficult or in some cases downright impossible. As arctic builders know, the slightest pin hole in their vapor barrier can result in frost buildup that inevitably melts, causing liquid water to soak into the fiberglass . Conventionally insulated walls are designed to dry to the outside of the building. The exterior of most modern homes consist of OSB plywood over the studs then a house wrap and then the siding. OSB ( oriented strand board) is a structural panel which is wood chips compressed together with glue. It is an excellent product which is extremely strong, however the glues that are used do not allow moisture to freely escape. Once the insulation is saturated the moisture cannot get back out the tiny hole it came into in the vapor form. Now there is a real problem. Rot and Mold. In buildings the ONLY effective way to control mold is to control moisture. Mold is moisture and moisture is mold.

In a conventional vented roof design, the attic is designed as a cold space that allows moisture to escape through the roof vents to the outside. This method was designed to allow for the inevitable penetrations in the ceilings vapor barrier. This method mitigates to a certain extent the moisture problems in the structures ceiling. However now there is a thermal problem that arises. Cellulose is the predominant insulation that is used in attic spaces today. It is a very loose fluffy material that is made out of recycled, ground up newspaper. Because of the looseness of this material when the upper surface is exposed to the vented attic, the cold, moving, outside air is allowed to freely mix with the interior of the insulation. This drastically reduces the thermal performance of the insulation. How often have you driven past a home where you see the frost melted off the roof in places other than the roof vents. The energy that the homeowner paid for is responsible for this.

This is not the fault of the builder. Alaska’s builders are doing the best job they are capable of with the only reasonably priced materials they have to work with.


The solutions…


Most builders in Alaska are familiar with rigid urethane foam. It is a very dense micro cellular plastic that is sprayed on and allowed to react and expand in place to conform to the cavity it is sprayed into. This product performs phenomenally and can address all of the problems stated previously in this document. However it is very expensive. It is often beyond the reach of the common middle class homeowners budget.

All is not lost however. Now Alaska ’s builders have available a high performance insulation that is only marginally more expensive than conventional fiberglass insulation. It is called BioBased 501. www.biobased.net

BioBased 501 is a soybean based spray foam that is designed specifically for these building challenges. It is a very light polyurethane foam that when sprayed on quickly expands more than 100 times its volume and fills even the tiniest crack and crevice achieving a perfect air seal within the stud or rafter cavity. Now you have a air sealed, wind-proof thermal envelope that eliminates those nagging drafts around electrical outlets that all Alaskans are familiar with. A vapor barrier is not necessary in most applications as it is a documented fact that 99% of vapor transmission through a wall or roof assembly is from air movement. BioBased 501 is an air barrier system and as there is no plastic on the inside wall surface, the remaining 1% of water vapor that may build up in the wall cavity is allowed to safely dissipate and dry to the inside. BioBased 501 is a totally water blown product which has no CFC‘s, HCFC‘s, VOC’s and no harmful off gasses. It was recently voted outstanding green product of the year. It achieves a class 1 fire rating (the highest fire rating an insulation can receive) BioBased 501 is rapidly becoming the obvious choice for educated builders and homeowners across the nation. BioBased 501 customers can typically enjoy as much as a 50% reduction in heating bills over fiberglass insulation and to further offset the higher initial cost of this product, plan early as many common building methods are no longer necessary with the use of BioBased 501.