ASHRAE 62.2 requires a air exchange at a rate of 7.5 cfm per person plus.........../

[59TTY]

RE: .. DAILY ATTIC AIR EXCHANGES?

ASHRAE 62.2 requires a air exchange at a rate of 7.5 cfm per person plus 3 cfm per 100 square feet. Is your attic ventilated?

7.5 cfm per person = 15 cfm ( 2 Occupants)

3 cfm per 100sqft of attic space = 54 cfm

-----------------------------------------------------------

Total = 69 cfm

(Balanced venting system/50% intake - 50% exhaust)

Example: Home with 10.000 cu ft Attic space.

a) (continous soffit intake - Cobra Ridge Vent/ 3/4" filter mesh)

b) (continous soffit intake - Metal Slant-back roof exhaust)

<> a) According to ASHRAE 62.2, - - how many daily attic air exchanges would be required, to reach the minimum Code requirement?

<> b) According to ASHRAE 62.2, - -how many daily attic air exchanges would be required, to reach the minimum Code requirement ?

Formal education will make you a living; self-education will make you a fortune. -- Jim Rohn

 

[conarb]

62.2 has nothing to do with attic ventilation, ASHRAE has recently drastically increased ventilation requirements due to codes sealing up our new "chemically active homes". If you look at the answer to the question on this site you will see an easy to use calculator, this is the result of a several year lobbying effort on the past of the fan industry, their end result is sealing up buildings to make them air-tight, then pumping is so much outside air that it costs more than before we sealed them up, this leads to expensive air-exchange systems called ERVs and HRVs, I am seeing them cost $6,000 to install and several hundred a month to operate, all in the name of saving energy.

 

[Gregg Harris]

Counter intuitive at its best. The end result is more expensive than the purported energy savings

 

[ICE]

Counter intuitive at its best. The end result is more expensive than the purported energy savings

That's true with the houses conarb deals with. I'll never see a $6000.00 ERV. Heck I couldn't get past the gate.