Insulation materials run the gamut from bulky fibers such as fiberglass, rock and slag wool, and cellulose to rigid foam boards and sleek foils. The best insulation materials provide good R-values and resist moisture.
Insulation should be installed by trained professionals. However, do-it-yourselfers can find guidance from manufacturers. Some insulation products require special installation techniques to minimize air leakage and moisture infiltration.
Cellulose
Cellulose insulation is made from recycled paper and can be dense packed or dry blown. It is a great choice for retrofitting existing walls as it can fit around pipes and wiring and flow easily, minimizing gaps that reduce energy efficiency. It also provides a tight seal from air infiltration and convective airflow and helps to dampen noise levels, according to an online study by the University of Colorado School of Architecture and Planning.
It can be used in attics, wall cavities, and floors. It can be loose-fill in attics or spray-applied in new construction. It is a cost-effective option for upgrading old homes and can help to increase the energy efficiency of existing buildings and reduce greenhouse gas emissions.
While cellulose is a green option, it is important to remember that the recycled materials used in this insulation aren’t without their own environmental impacts. The material is treated with boric acid or borax to prevent fire and mold and to make it less attractive to pests. This treatment isn’t known to be toxic or harmful to humans, but it does use up valuable fossil fuels.
The good news is that cellulose has a lower embodied energy than fiberglass and other furnace-produced mineral insulation materials. Additionally, the material is produced at regional centers rather than shipped and rolled out, cutting down on transportation costs.
Fiberglass
Fiberglass is well-known in the construction industry as an insulator for its affordable and effective properties. This spongy material traps pockets of air, which helps keep rooms thermally regulated and reduces sound transmission between floors or walls. It is also a noncombustible material, making it safe to use in structures where fire resistance is a priority.
Another benefit of fiberglass is its ability to resist moisture, which can help prevent the development of mold and mildew within wall cavities or between framing members. This is important in regions that experience high levels of humidity.
Homeowners can install fiberglass insulation themselves, but they may need to work with a professional to ensure that the insulation is placed properly. This is because gaps in the insulation will allow heat to move more freely, reducing its efficiency. In addition, many fiberglass products are treated with borate and/or EPA-registered fungal inhibitors to provide protection against pests and moisture.
For builders, fiberglass is available in rolls and batts of various thicknesses to fit any building frame or piping. The thickness of the insulation determines its R-Value, with thicker insulation offering higher R-Values. For example, an inch of fiberglass insulation has a R-Value of 3.2, while two inches of the same material will offer an R-Value of 6.4. This can significantly increase energy efficiency and provide a significant return on investment.
Structural Insulated Panels (SIPs)
Structural insulated panels (SIPs) are an effective insulation material that reduces energy costs in homes or buildings. They provide an air-tight building envelope and significantly lower drafts compared to traditional frame construction. In addition to reduced heating and cooling costs, SIPs also help to prevent moisture damage in homes or buildings.
Made from oriented strand board and expanded polystyrene, SIPs are strong, termite resistant and outperform timber framed buildings in terms of both acoustic and thermal ratings. They can be used as walls, floors or roofs and can reduce the overall construction cost of a home or building.
SIPs are fabricated in advance and shipped to the building site ready for installation. This increases the efficiency of construction as there is no need for carpenters to assemble stick framing on-site. It can take up to 50% less time to construct a SIP home or building than a conventional wood frame structure.
While the strength and energy efficiency of SIPs are impressive, there are a few concerns to keep in mind. For instance, the foam insulation can be susceptible to rot, mildew and mold when exposed to moist environments. This can be mitigated by installing a waterproof surface on the walls and using heat ventilators in humid areas.
Another downside is that since SIPs are precision engineered, they don’t allow for changes to plumbing or electrical lines after the building is erected. This is because holes are pre-drilled into the building, so any alterations will compromise the integrity of the system.
Blanket Batts and Rolls
Blanket insulation is the most popular type used in residential construction. It is inexpensive, easy to install and can be found in most stores. It comes in pre-cut panels that are called “batts” and are typically made of fiberglass, mineral wool or other natural fibers. It is also available in rolls that can be hand-cut and trimmed to fit.
These rolls are often used in attics, floors and ceilings of new construction projects. They are generally made of fiberglass, mineral wool, or other natural fibers, and can be found in different R-Values depending on climate and the level of insulation needed in each area. They are often more affordable than other types of insulation and are more easily available, but can have a difficult time fitting into nonstandard spaces that can include pipes, wiring or other obstructions.
Unlike rolled and batt insulation, blown insulation requires the use of a special blowing machine for installation. It is usually made from materials that are a mix of recycled content, such as cellulose or a mixture of fiberglass and blown glass. However, blown insulation is more expensive than blanket batts and rolls because it is more labor-intensive to install. It can also be prone to air leaks due to loose seams and gaps. Additionally, blown insulation can have a lower R-Value than blanket insulation.