Attic Temperature Differential Winter

I only had r 19 up there added another 30 on top of it and noticed the old insulation was crammed right tight to the sheathing.

Attic temperature differential winter.

Yesterday s outside temp topped at 91 f inside temp 78 f a c off all windows closed and attic 112 f. Interior attic air exterior air inner and outer sheathing and internal rafter temperatures of black and white shingled chambers were monitored. Is there any rule of thumb for attic temps compared to outside temp. When i left for work in the morning outside was 73f inside 74f attic 75f i m happy with the interior only creeping up 4 degrees a c off windows closed is the 21 degree differential temp ideal for an attic in the n.

Snowpack on a roof covering vents of any type alters the airflow from ventilation thus altering the. Ideal attic temperatures shouldn t be more than 10 to 20 degrees hotter than outside temperatures. As snow accumulates it alters the temperature profile of an attic and roof surface. Temperatures were measured using thermocouples and recorded over a 3 year period from october 1991 through september 1994 using a datalogger multiplexer device.

The cooling load for a home air conditioner depends on the difference in temperature between the inside and outside air and reduction of attic temperatures from 155 degrees to 105 degrees f will result in a significant reduction in cooling load. The white roof lowered the attic temperature by about 20 f. If your attic soars above 100 degrees and reaches the 150 mark its time to consult. Your attic temperature should be at or near the outside air temperature if it is well ventilated and does not leak warm air into the attic from below.

These images came from a presentation danny parker gave pdf on fsec s cool roof research the third graph shows attic temperatures from the middle of the attic for several different types of roofing as well as a sealed attic.