Spray Foam Insulation and HVAC systems

Insulation is a much-needed feature for homes. Not only does insulation help maintain perfect conditions within a home, but it also helps drastically reduce energy consumption costs. One form of insulation that is fast gaining popularity in many homes is spray foam insulation.  With spray foam insulation, latex or polyurethane foam is applied to spaces directly using a spraying mechanism. The material then dries up and seals these spaces airtight, resulting in perfectly insulated surfaces. Hot air can neither escape outside nor penetrate into a room. While many people opt for this method of insulation due to its impeccable airtight sealing quality, few understand the implications of this when they have a HVAC system installed in their home.

Atmospheric combustion HVAC systems

Atmospheric combustion HVAC systems are common in older houses. Some new houses also feature this form of air condition. Atmospheric combustion systems need to draw air from the outside, warm the air, and then dispel it to the regions where heating is required. Some of these systems are located in well-ventilated attics, while others are located below, in the rooms they need to air condition. If your system is located in the attic, it may not be a good idea to spray foam the attic and completely seal off the HVAC system's source of outside air.

Some contractors spray foam the attic but leave holes around the gable vents in such a situation. The holes act as air draw-in vents for the HVAC. Atmospheric combustion systems located below the attic are supposed to have vents that run all the way up to the roof. These vents would bring air to the HVAC system if the attic were spray-foamed airtight. When insulating an attic that has these vents, do not spray the foam directly on the metallic vents. It may pull away and break the insulation layer, among other problems associated with doing so.

Best HVAC options

If you intend to spray foam your home, it is best to install HVAC equipment that works with either sealed combustion or power venting. These machines do not require an open air source. Another better option would be to use direct ventilation HVAC systems. The channeling will be done from the source of air to the heating or cooling apparatus, and then the air will be directly vented into rooms. In this case, foam spraying would be an ideal method of insulating the home, without interfering with proper functioning of your HVAC system. Work with professional insulation contractors, and they will give you the best advice on how to insulate your home, with the proper materials at the right R values.