Keeping your Central Florida Home Comfortable with Spray Foam Insulation
Spray foam insulation has been increasing in popularity throughout Orlando over the last several years. While initial costs are more expensive than traditional insulation, there can be significant long-term energy savings.
This is because spray foam is not only an effective insulator but also a powerful air sealing agent. Sealing restricts air movement through the building envelope. If air moves through insulation, the R-values are diminished. Air sealing also reduces the natural ventilation rate (or air leakage rate), further reducing heating and cooling loads.
All sounds good, right? But natural ventilation dilutes the concentration levels of pollutants generated inside the home. Studies show that without it, dust, allergens, moisture, and other pollutants can build up to unhealthy and even dangerous levels. Therefore providing mechanical fresh air ventilation is especially important in spray foam houses. Cooking, showering, breathing, and other day-to-day activities generate a moisture load that needs to be removed. If the house is sealed tight with spray foam, it is much harder for this moisture to leave the house naturally. It builds up inside the home and can raise relative humidity to uncomfortable and even dangerous levels. While it is recommended by the spray foam manufacturers and installers, for spray foam homes to have some form of mechanical ventilation, there are many questions on how best to provide it.
The most common strategy being practiced throughout the country is using an Energy Recovery Ventilator (ERV) – but is this best solution? ERVs are a balanced ventilation system originally developed for northern climates. They bring air into the home and blow an equal amount of air out of the home. The ERV core transfers some heat and moisture (energy) between the two air streams. But the energy transfer isn’t perfect. As a result, during our typical summer conditions in Central Florida’s hot/humid climate, additional moisture is added to the home when ventilating. With each additional air change, even more moisture is added. As moisture from the ventilation is combined with the internal moisture loads, the relative humidity can quickly climb out of control. To make matters worse, the air conditioner’s run time is reduced due to the spray foam’s effective thermal insulation, meaning less ability to remove moisture.
The best solution for mechanical ventilation in Central Florida’s humid climate is a whole house ventilating dehumidifier installed by 4 Seasons. Most dehumidifiers are capable of bringing in filtered outside air, putting the house under a slight positive pressure and dehumidifying the air as necessary. In addition to dehumidifying the air brought in for ventilation the units also maintain interior humidity 24/7 independent of the air conditioning system. We look forward to guiding you in the selection of the proper size unit, location of the air intakes, system control options and installation details.