Author Topic: Install height  (Read 457 times)

Offline bsolc

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Install height
« on: April 01, 2019, 10:10:02 AM »
What do you guys typically allow for height above furnace. 70" floor to ceiling height. 35" furnace with a coil above. 40000 btu furnace 2 stage. Dont have case coil to match 40000 furnace so would have to get standard coil cut in duct and put in drain pan.

Thanks

Offline Admin

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Re: Install height
« Reply #1 on: April 01, 2019, 03:16:09 PM »
In new construction you need to follow Table 9.5.3.1 and leave 83" ceiling height clearance in 75% of the basement, except under ducts and beams this can be reduced to 77" in the remaining 25% of the basement. 

We usually install the plenum so the top of any takeoff is 1" away from the underside of the floor joists.  This way the square duct can also be kept 1" away from the floor joists where clearance to combustible codes apply.

Install the return square duct tight to the floor joist so you can install joist lining where needed.