The Problem
Despite its beaches and beauty, Florida was only the 21st most populated state in the country before residential air conditioning existed. The heat and humidity in Florida is so extreme that any basic method for slowing heat transfer will make a difference in the heat load on your air conditioner. This makes it simple for contractors to blow insulation out of a hose (like they're watering a garden) and make an immediate impact.
However, this does nothing to stop the biggest source of heat gain in a Florida home: air leakage.
The Data
| Finding | Source |
|---|---|
| Air leakage accounts for 30–70% of a home's heating and cooling load — yet most contractors never test for it | Nate Adams, "The House Whisperer," The Home Comfort Book |
| Florida attic temperatures regularly reach 130–160°F in summer, forcing your AC to fight heat from every direction | Florida Solar Energy Center / U.S. Department of Energy |
| Homes with air handlers located in the attic use 30% more cooling energy than homes with handlers elsewhere | Florida Solar Energy Center — study of 48 Central Florida homes |
| 20–30% of air moving through a typical duct system is lost before it ever reaches a room | Energy Star / EPA |
| Air leakage alone accounts for up to 30% of total heating and cooling energy consumption — independent of duct loss | U.S. Department of Energy |
The Explanation
Starting a blown-in insulation company requires very little building science knowledge, very little HVAC knowledge, and very little money. All that's needed to get started is a vehicle to transport the insulation and the blower machine. Big box stores will rent the blower machines to the public for free if you buy enough bags of insulation. Of course, there are more industrial blower machines available and companies can buy direct from distributors instead of big box stores, but the fundamental simplicity of blown-in insulation remains the same: anyone can do it.
However, just because it is simple does not mean it is easy. Florida attics still reach temperatures in excess of 150 degrees, there is often very little light, and the potential to fall through your ceiling is very high. It is grueling work. The hard physical labor is what you're paying for when you hire a company, not building science or technical expertise. It is very common for companies to hire folks willing to do this hard manual labor for often little pay who may not be able to gain employment otherwise.
Spray foam insulation, on the other hand, requires a significant capital investment to get started. For a spray foam rig that is built for the Florida climate, the price tag easily exceeds $100,000 — not including the cost of a pickup truck to haul it. This fact prevents a lot of contractors from selling or recommending spray foam, although there is a budding market for used equipment, basic equipment, or equipment from countries like China where manufacturing standards are not as stringent as in the United States. This second-hand or cheaper equipment is one of the biggest causes of spray foam failures, because it is not calibrated to keep humidity out of the system, has not been maintained properly, and because it does not assure the applicator that they are spraying an equal 1:1 ratio of isocyanate and polyol blend, which are the two base chemical components used in making spray foam.
The second biggest source of spray foam failure in this industry is contractor ignorance. Spray foam is, shockingly, an unregulated trade in the United States. There is no formal educational requirement to get started in spray foam like there is for an HVAC, electrical, or plumbing contractor. This is extremely irresponsible, because although spray foam is the most powerful, versatile, and strongest insulation type there is, it also can be — and often is — done horrifically wrong by untrained contractors who give the entire industry a bad name. The truth is, contractors need to be familiar with chemistry, HVAC, roofing, and thermodynamics to even begin doing a professional job for you. Then they need high-end equipment and strict standard operating procedures for their crews.
What This Means for You
Don't be afraid of foam because of a fiberglass (or cellulose) contractor not educated on it or financially capable of applying it properly. For a typical homeowner, this results in a lot of unnecessary confusion and fear due to all the contractor bias, misunderstanding, and misapplication. So what do many homeowners do? They play it safe, and understandably so. But many homeowners would prefer to get the most impactful option — spray foam — if they were able to be reassured that it would be done correctly and last as long as advertised. The only way to know which solution is right for your specific home is to test it first, before anyone picks up a hose or opens a bag of insulation.
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