Fiberglass Blown-In Insulation

Fiberglass insulation is a commonly used material for insulating dwellings, available either as blown-in insulation or batts for professional installation. Made from recycled glass combined with sand, fiberglass insulation enhances sound deadening and resists water absorption. However, it’s crucial to address any existing leaks or similar issues before insulating to prevent potential water damage.

The energy efficiency and environmental friendliness of fiberglass insulation continue to improve, mirroring advancements in other insulation products. Theoretical expectations suggest that heat transfer through fiberglass insulation between two opaque, isothermal walls occurs via radiation and conduction. Glass fibers, depending on their size and direction, can absorb, emit, and scatter light anisotropically. Determining bulk scattering and absorption coefficients, as well as phase functions in the radiative transport equation, involves using measured spectrum optical constants of glass, along with fiber diameters and orientations. An iterative solution of the energy problem and the discrete ordinate approximation to the radiative transfer equation are both necessary for coupling radiation and conduction. It’s found that approximately half of the total heat transfer is due to radiation and the other half to conduction, resulting in a nonlinear temperature profile.

To ensure proper heat retention and maximize utility bill savings, fiberglass insulation should be topped off at a height of 20″-21″ (R-value of 60).