My house is not insulated. What are the best ways to add wall insulation? Or is it better to just add more attic insulation?

Asked by Bill
Rancho Palos Verdes, CA

We have a ranch-style house and no AC. The ocean breezes keep us cool most days in the summer.


Rancho Palos Verdes in California has, most of the year, a very moderate and mild climate requiring heating and cooling only on a limited number of days.

Nevertheless, a well-built and state-of-the-art insulated building envelope will increase the energy efficiency and comfort of the individual home. A holistic analysis of all the elements that are part of the building envelope (roof, walls, floor, windows and doors) is recommended.

The upgrade can be implemented in multiple phases, which allows maximum cost control over the renovation project.

  • Roof and wall insulation are critical since those are the largest surfaces of homes.
  • Adding attic insulation is, most of the time, easier, since the area is accessible in comparison to the wall insulation.

The following options can be considered.

  • Option 1: Removing all interior drywall and adding traditional batt insulation into the cavity between the wood studs. This is a major remodel and difficult if you plan to live in your home during construction.
  • Option 2: Injecting foam insulation into the cavity between drywall and exterior stucco by drilling injection holes only. Limited interior damage -- no guarantee that all cavities are completely filled with foam providing expected insulation value.
  • Option 3: Application of exterior insulation on top of existing wall with new thin stucco finish. Exterior work with new exterior building appearance -- no interior damage.



For more information:

Read "I want to add wall insulation to my 1920 home. I have two locally available options -- Icynene and Tri-polymer foam. Can you advise me?" a Q&A answered by Alex Georgiou.

Also, read "I have a soyfoam insulation estimate for the first floor walls of my 40 x 80 sq ft home built in 1976. Is $4250 worth it?" a Q&A answered by Cynthia Phakos.

Tagged In: cellulose insulation, insulation, spray foam

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