Plan How to Upgrade Your Wall Insulation Project Carefully
Homeowners must plan their wall insulation project carefully. Please note exterior wall insulation projects feature two basic options:
- Without removing the interior or exterior wall surface, or
- Removing the wall surfaces.
Let’s review the standard applications.
Blown-in Insulation Without Removing the Interior or Exterior Wall Surface
Installation of wall insulation in an existing wall without removing the interior or exterior wall surface, requires loose-fill cellulose or fiberglass insulation. Additionally, the fiberglass insulation specifically works in exterior walls. Also, homeowners require an insulation machine capable of dense-packing the insulation in the wall cavity. This ensures it completely fills the cavity and stops any air leakage between inside and outside of the wall. This process of blowing insulation into wall cavities under pressure is called “dense-packing”.
To gain access to the exterior wall cavities, holes must be drilled into the exterior wall sheathing or the interior sheetrock or plaster. To drill holes into the exterior sheathing, remove the exterior siding and replace it after the insulation installation. Unless, homeowners install new siding upon completion of the wall insulation project. For homes built before 1978, ensure all work complies with lead paint safe work practices. And, some homes still contain asbestos siding, so keep this in consideration as part of any wall insulation project.
Or, if preferred, drill holes from the inside through the sheetrock for blow-in insulation into the walls. The process of blowing insulation from the inside surface of exterior walls remains messy. The project creates lots of dust and disrupts day-to-day lives until the project ends. Additionally, it is critical for insulation to be installed in ALL wall cavities including those above and below windows or wall cavities above and below fire-blocking, bracing or horizontal framing. Upon completion of the insulation work, seal the holes and re-install the exterior siding. If applicable, re-install and/or repaint the interior sheetrock or wall as well.
Upgrading Your Wall Insulation when the Interior or Exterior Surface has been Removed
If the homeowner removes the interior wall surface (sheetrock or plaster) to gain access to the exterior wall cavities, the insulation options become different. The open wall cavity needs fiberglass batts insulation that fills the entire framing cavity depth. It is important to install the insulation according to the manufacturer’s instructions around pipes and wires that are in the wall. Additionally, many homeowners use an air barrier material with the fiberglass batts, which minimizes air intrusion into the wall cavity.
Alternatively, homeowners frequently choose spray foam insulation for filling a wall cavity. Both open cell and closed cell spray foam offer good insulating and air sealing performance for homeowners. However, since closed cell insulation offers a higher R-value per inch, most homeowners prefer this insulation.
Insulating exterior walls remains challenging. It requires experience, special tools, powerful insulation machines and, in some cases, special training because of certain surfaces contaminated with lead paint or asbestos. Therefore, homeowners obtain the best results from working with an experienced contractor trained and equipped for this type of work. An experienced contractor helps you determine:
- Are there any existing health or safety concerns to be considered as part of your wall insulation project?
- Is it better to work from the inside or outside of your home to install wall insulation?
- Is it better to remove the interior or exterior surface of your home or leave them alone and drill through them to install wall insulation?
A quality contractor helps determine the best approach for proper exterior wall insulation. Once insulated, the exterior walls in your home perform at a very high level offering maximum comfort with minimal energy cost.