The Stack Effect: How a hot attic affects your whole house. The ways to improve the energy drain with spray foam insulation spray foam and balanced HVAC.

 In the Southwest, as spring and summer arrive, we receive more customer calls about rooms becoming uncomfortably hot, mirroring the rise in outdoor temperatures. Every year, around mid-June, rooms above many property owners’ garages become excessively warm and stuffy. The temperature on the second floor of their homes keeps increasing regardless of the thermostat setting. Their home air conditioning unit struggles to keep up, and with the rising cooling bills, so do their finances! 

It’s a common misconception that insulating the garage or garage ceiling will help better regulate the temperature in the rooms above it, but that’s actually not the case! The area that should really be addressed first is the home’s attic. 

By 10 a.m. on many hot Arizona days, a home’s attic heats up to the point that too much air is being expelled, and not enough fresh air is coming in from the soffits. Oftentimes the soffits are not sized correctly, and as they become clogged with debris through the years, the open soffit vent space is reduced. Even with brand new homes, soffits are typically not balanced properly, and won’t provide the right amount of air flow.

This puts a negative pressure on the entire home and the comfortable cool air that is being pumped within it. Outside air begins to get pulled inside from windows, doors, and other openings, increasing indoor humidity, and sending the  HVAC into overdrive. This phenomenon is called the Stack Effect.

How spray foam insulation Your Attic Can Stop the Stack Effect 

By sealing your attic with a spray foam solution, you effectively create a "lid" on your home, preventing the Stack Effect and keeping out excess moisture, harmful allergens, and property-damaging pests. Spray foam boasts a high R-value, meaning it has a strong ability to resist heat and block outside air and elements. 

If you experience uncomfortably hot rooms in your home for half the year, simply insulating your garage will have limited impact. However, encapsulating your attic will significantly enhance the quietness, cleanliness, and comfort of your entire home. Using top-quality spray foam insulation in this area reduces air loss from your home while also improving indoor air quality! 

Enjoy the Many Cost-Saving Benefits of Spray Foam Insulation 

Energy Savings of Spray Foam Insulation

Now your home’s HVAC can run more efficiently, and you’ll see a reduction in your heating and cooling bill  immediately. In fact, according to a recent Department of Energy study, homeowners who installed spray foam insulation saved an average of 20% on their year-round energy costs. 

Longevity of Spray Foam Insulation

Homeowners are looking for an insulation product that won’t require frequent updating and lots of ongoing maintenance. Spray foam insulation should last throughout the lifespan of a structure, or approximately 80-100 years. It does not lose its shape or ability to resist air and moisture over time, as many common insulation materials do, saving time, money, and frustration for years to come.

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The Stack Effect - Fine Homebuilding

BPI Phrase of the Month: Stack Effect

Tax Benefit of Spray Foam Insulation

A new Spray Foam Insulation Tax Credit is effective for products purchased and installed after January 1, 2023. U.S. residential homeowners can claim 30% of product costs, with a maximum credit amount of $1,200. This credit can be combined with other energy efficiency credits, for a total max credit of $3,200 per year. 

When you combine these incentives with the many other benefits of spray foam insulation, the decision to encapsulate your attic with spray foam (and put a stop to the Stack Effect in your home once and for all) is a no-brainer!