Of course spray foam is very expensive so i am not sure i want to spring for it in the larger attic which could be addressed with traditional insulation.
Builder sprayed insulation all over furnace in attic.
The good news is that some installers understand this problem and seek to address.
Unvented attic sealed furnace and gas water heater.
Actually has better than 15 months of operation.
Most often the attic is sealed by installing spray foam insulation at the roofline thus bringing the attic inside the building enclosure and turning it into conditioned space directly or indirectly.
Earlier this year i got a question about a home that had spray foam insulation in the attic.
If you don t have a crawl space or a basement then it can be a challenge to place a furnace on the ground floor of the structure.
Yesterday i was at a home we completed unfortunately i was only the ac contractor on this home over a year ago.
We mean that literally by the way.
What do you all think.
Attics with spray foam insulation are so cool.
You might not receive the same air movement benefits if the unit is in a garage either.
A lot of builders and homeowners are going with spray foam insulation because of the airtightness benefits but then the questioner mentioned that the spray foam contractor had intentionally left big holes to the outside by not sealing the gable vents.
A furnace can suffer from a drop in energy efficiency if it s in an unconditioned space such as an attic.
Most of the issues that furnace might experience in an attic are due to extremely cold weather in this poorly insulated space.
In cases where there has been a furnace in the attic i have put a grill in the pull down stairs to insure there is enough air getting into the house.
I found instead a vintage 3 ton ac unit with 1 rigid insulation taped all over it and insulated flex duct snaking all over the poorly insulated attic.
A furnace in the attic is a design that works for all homes.
Sprayed foam insulation ac loads calculated by energywisestructures.
A while back i wrote about the incompatibility of putting an atmospheric combustion furnace in a sealed attic.
When you insulate the top of your attic with spray foam you re bringing your attic into your home s envelope as a result you can reduce the temperature in your attic by a lot anywhere from 120 degrees to around 95 during peak summer.
If we insulate to r60 that attic is going to be mighty cold in the in winter and hot in the summer.
Should i worry about the furnace in the attic.
The concern with a furnace in an unvented attic is to be sure there is enough combustion air so the furnace has adequate air for combustion and drafts properly.
Nothing unusual about that.
