Well mainly it s a way to save space.
Hot attic air conditioning.
Most updated central air conditioned homes have a new air conditioner split system meaning the ac is broken up into parts.
And it can cause your air conditioner to work harder than it needs to and send your energy bills soaring with the temperature.
With that said a room air conditioner with just a nominal or average cooling capacity even if rightly sized will be forced to work harder.
Intake vents located at the lowest part of the roof under.
An outdoor unit which houses the fan condenser and compressor and an indoor unit which holds the evaporator and fan.
Typically this indoor unit gets placed in a cabinet or closet somewhere inside.
An overheated attic can bake asphalt shingles on the roof and cause them to deteriorate.
In fact most of the time the temperature inside an attic is even hotter than the outside climate.
Mini split ductless air conditioner.
An unventilated attic can reach 150 degrees in the heat of summer 50 degrees higher than it should be.
Low cfm similar to a bathroom vent 300cfm and only in the hot spots basically by adding an inline ducting fan to the return ducts for the hotspot rooms.
Cool air in hot air out attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents.
My idea is to vent the build up of hot air that has risen to the ceiling in the hotspot rooms into the attic so that air from cooler parts of the house can move in.
Portable air conditioners do need to be vented to pump the hot air outside.