An Alternative to Fiberglass Insulation
Until recently, most homes and many building utilized fiberglass insulation for both wall and ceiling insulation. This gives an R-value of approximately 19 in a two by six framed wall (six inch thick wall). Now, there are several innovative alternatives to fiberglass.
Two of these are in the form of spray foam insulation. Two brands are coming into general use; one is the Icynene spray foam system and the other is BioBased spray foam. Both of these are applied as a liquid spray to the structure after the framing, plumbing and electrical wiring are installed, but prior to the sheet rock installation. These foams can quickly expand to as much as 100 times the original liquid volume, within 17 seconds or less. Unlike fiberglass and other solid poured fill or blown insulation, this will totally fill all voids. This creates an airtight barrier that is far more effective than fiberglass, which often settles or pulls away from the studs. Thus, drafts and infiltration effectively controlled, and heat loss is significantly reduced.
Another benefit of these spray foams, is that they do not emit toxic off-gassing, or do they contain formaldehyde. In addition, they do not contribute to or support the spread of fire, unlike some of the prior polyurethane or other foam products.
The Icynene system is composed of polyicynene, and is a one-half pound density-free open cell material with an R-Value of 13 for a two by four framed wall,or R-20 for a two by six framed wall. This makes the R-value itself comparable to that of batt or blown fiberglass, but the similarity ends here. What makes a system such as Icynene spray foam it its ability to control infiltration. Infiltration is a major cause of heat and cooling loss in buildings. Thus, the total end results are much less fuel consumption and greater indoor environmental comfort and health.
Of special interest to projects pursuing LEED certification is the BioBased spray foam product. This is applied in a similar fashion to that of Icynene. While it is a polyurethane product, it is made from soybeans, which are a rapidly reproduced renewable resource, making it qualify for a LEED credit in the Rapidly Renewable Resources Area. The BioBased 1701 closed cell product is also Green Guard Certified and does not contain CFCs, VOCs or HCFCs in the finished cured form.
There are two forms of BioBased spray foam, an open cell, Biobased 501 semi rigid open cell that has an R-value of 13 for a three and one half inch wall, while the closed cell BioBased 1701 has an R-value of 19 for the same 3 and one-half inch wall, or close to R-30 for a six inch wall, making it an exceptional insulator as well as superior vapor barrier. NOTE: In certain climates, additional vapor barriers may be needed; this MUST be evaluated for each area.
Both Icynene and BioBased spray foam will not support mold or bacterial growth, eliminating this major problem if moisture should ever come in contact with it, during perhaps, a severe storm or other event that causes structural damage. In addition, they are not attractive to rodents.
The fact that soybeans are the basis of this product, and that they are grown right here in the USA, accomplishes several objectives in addition to the insulation values. First, the petroleum based price fluctuation issues are avoided. Secondly, the product is resourced and manufactured in the USA, and in some cases, within the 500 mile distance of many installations, adding an additional LEED credit, use of locally resourced and produced products. Moreover, BioBased products support the USA farming economy.
For BioBased Spray Foam to certified for a LEED home project, it will be necessary for the contractor to have a HERS rater (a person certified to perform home energy ratings) verify that the proper materials have been installed.
One important note about making a building air tight MUST be addressed. This is the need for controlled ventilation by mechanical means. In general, rather than relying on opening windows, a device known as a heat recovery ventilation system is installed as part of the HVAC system that removes stale air and brings in fresh air at the required rate per hour, as specified by the ASHRAE. In this process, over 70 percent of the heat or cooling is reclaimed by the heat recovery system. In humid conditions, the incoming air is dehumidified, while in very dry conditions, humidity may be added as needed to the incoming air. In addition, many of these systems are equipped with HEPA air filtration systems as well, to reduce airborne pollutants such as mold spores and pollen. As a result, the building air quality is substantially improved, leading to a much healthier living environment. If a homeowner merely relys on opening windows, or worse yet, creating a loose fitting, non-airtight building, they not only waste energy, but bring in all the outdoor pollutants as well.
Two of these are in the form of spray foam insulation. Two brands are coming into general use; one is the Icynene spray foam system and the other is BioBased spray foam. Both of these are applied as a liquid spray to the structure after the framing, plumbing and electrical wiring are installed, but prior to the sheet rock installation. These foams can quickly expand to as much as 100 times the original liquid volume, within 17 seconds or less. Unlike fiberglass and other solid poured fill or blown insulation, this will totally fill all voids. This creates an airtight barrier that is far more effective than fiberglass, which often settles or pulls away from the studs. Thus, drafts and infiltration effectively controlled, and heat loss is significantly reduced.
Another benefit of these spray foams, is that they do not emit toxic off-gassing, or do they contain formaldehyde. In addition, they do not contribute to or support the spread of fire, unlike some of the prior polyurethane or other foam products.
The Icynene system is composed of polyicynene, and is a one-half pound density-free open cell material with an R-Value of 13 for a two by four framed wall,or R-20 for a two by six framed wall. This makes the R-value itself comparable to that of batt or blown fiberglass, but the similarity ends here. What makes a system such as Icynene spray foam it its ability to control infiltration. Infiltration is a major cause of heat and cooling loss in buildings. Thus, the total end results are much less fuel consumption and greater indoor environmental comfort and health.
Of special interest to projects pursuing LEED certification is the BioBased spray foam product. This is applied in a similar fashion to that of Icynene. While it is a polyurethane product, it is made from soybeans, which are a rapidly reproduced renewable resource, making it qualify for a LEED credit in the Rapidly Renewable Resources Area. The BioBased 1701 closed cell product is also Green Guard Certified and does not contain CFCs, VOCs or HCFCs in the finished cured form.
There are two forms of BioBased spray foam, an open cell, Biobased 501 semi rigid open cell that has an R-value of 13 for a three and one half inch wall, while the closed cell BioBased 1701 has an R-value of 19 for the same 3 and one-half inch wall, or close to R-30 for a six inch wall, making it an exceptional insulator as well as superior vapor barrier. NOTE: In certain climates, additional vapor barriers may be needed; this MUST be evaluated for each area.
Both Icynene and BioBased spray foam will not support mold or bacterial growth, eliminating this major problem if moisture should ever come in contact with it, during perhaps, a severe storm or other event that causes structural damage. In addition, they are not attractive to rodents.
The fact that soybeans are the basis of this product, and that they are grown right here in the USA, accomplishes several objectives in addition to the insulation values. First, the petroleum based price fluctuation issues are avoided. Secondly, the product is resourced and manufactured in the USA, and in some cases, within the 500 mile distance of many installations, adding an additional LEED credit, use of locally resourced and produced products. Moreover, BioBased products support the USA farming economy.
For BioBased Spray Foam to certified for a LEED home project, it will be necessary for the contractor to have a HERS rater (a person certified to perform home energy ratings) verify that the proper materials have been installed.
One important note about making a building air tight MUST be addressed. This is the need for controlled ventilation by mechanical means. In general, rather than relying on opening windows, a device known as a heat recovery ventilation system is installed as part of the HVAC system that removes stale air and brings in fresh air at the required rate per hour, as specified by the ASHRAE. In this process, over 70 percent of the heat or cooling is reclaimed by the heat recovery system. In humid conditions, the incoming air is dehumidified, while in very dry conditions, humidity may be added as needed to the incoming air. In addition, many of these systems are equipped with HEPA air filtration systems as well, to reduce airborne pollutants such as mold spores and pollen. As a result, the building air quality is substantially improved, leading to a much healthier living environment. If a homeowner merely relys on opening windows, or worse yet, creating a loose fitting, non-airtight building, they not only waste energy, but bring in all the outdoor pollutants as well.
Posted by Alan L. Englander at 1/4/2009 8:39 PM 
Categories: Renewable Resources, LEED Credits, SprayFoam Insulation, Infiltration Seal
Categories: Renewable Resources, LEED Credits, SprayFoam Insulation, Infiltration Seal
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