Foam One-One

Building Science

Facts about Insulation


The most common form of insulation on the market, Fiberglass is the baseline for efficiency. While interior wall sound batts make for adequate sound abatement, fiberglass used thermally is somewhat limited in function without sealing penetrations, usually considered an upgrade with a fiberglass install.

Fiberglass is air permeable allowing air to move freely through its fibers which can lead to convective heat loss through walls, floor joists, vaulted roof lines, and ceilings. Installation mistakes are costly to effective R-Values. Performance is affected by faulty installation such as compressed batts or improperly sized cuts leaving dead space in the cavity, sometimes cutting insulation performance down below half the stated R-Value. This is a great example why choosing the right installer is imperative. Caulking and sealing around cripple studs, windows, and the bottom and top plate significantly improves fiberglass’ performance. Unfortunately, most crews ignore this crucial step. Talk to Foam-One-One about the best installation method to get the most out of your fiberglass insulation project.


Cellulose insulation will settle and compress over time reducing the original R-Value performance. As an air-permeable¬ insulation, air movement through cellulose reduces effective R-Value by as much as 50%. Convective currents caused by air movement in wall cavities can cause other problems. Reaching dew point inside the cavity makes condensation a real possibility, in fact, mold found inside envelope walls is often the direct result of bulk water spurred by convective currents present in air-permeable exterior walls.

What about other insulation types on the market?

The rest of the insulation market exhibits these characteristics: air-permeable, will sag and settle and compress over time, and incurs a high likelihood of improper installation. Cellulose, rock wool, blown-in-fiberglass, bib’s (blown-in-blankets), and denim (literally ground-up blue jeans) are generally cheaper in retail price, but will cost more month to month than the upgrade to spray foam insulation. Although R-Values are similar, spray foam will outperform the rest of the insulation market on comfort, air-quality, utility savings, sound abatement, and will increase the overall value of your property. These qualities make spray foam your insulation investment.