The system consists of two types of units.
Conditioned attic systems.
Lstiburek s enthusiasm was rooted in his desire to bring attic ductwork inside a home s thermal envelope.
The right terms should have been conditioned attics and conditioned roofs.
Unvented conditioned attics were quite rare before the 1980s.
Housing industry has been to locate hvac systems in unconditioned attics but this is highly inefficient.
Most of the heat generated in your home is coming from the roof and the attic adding heat gain to the upper levels.
These connect by a refrigerant line and a.
One outdoor condenser and the air delivering indoor units which you have at least one of or maybe four.
Most updated central air conditioned homes have a new air conditioner split system meaning the ac is broken up into parts.
An edited version of this insight first appeared in the ashrae journal.
An outdoor unit which houses the fan condenser and compressor and an indoor unit which holds the evaporator and fan.
Well mainly it s a way to save space.
Creating a conditioned attic without a hvac unit in the attic.
Hpca is a below roof deck engineered insulating system that dramatically lowers attic temperatures brings ducts into conditioned space and.
Most people desire cool homes for sleeping and bedrooms are often located on the upper levels.
So why put an hvac system up in the attic at all.
In what is turning out to be an unfortunate turn of phrase the terms unvented attics and unvented roofs have entered the lexicon.
This is very difficult for the system and the upper levels of most air conditioned homes experience unsatisfactory cooling.
For builders who locate hvac equipment in the attic space the propink high performance conditioned attic system is the affordable way to optimize home comfort durability and value per square foot.
The condenser in your air conditioner works hard to get rid of heat and pressurize refrigerant for the return trip through your house.
Attic hvac systems save space.
A lot of the blame for that goes to me and for that i am sorry.
If there is no hvac in the attic why not just air seal and insulate at the attic level much easier and less expensive.
Seems to me the only reason to create a conditioned attic is to bring the hvac system and ductwork into the thermal envelope of the home.
A fundamental requirement of an unvented attic assembly is the use of air impermeable insulation on the underside of the unvented roof to prevent air infiltration and exclude airborne moisture from the attic.
Building america research has demonstrated unvented conditioned attics can substantially improve energy performance while allowing home builders.
