DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   HVAC (
-   -   Proper CFM for a dedicated room (

Mijotter 04-12-2013 09:47 PM

Proper CFM for a dedicated room
As far as CFM's required. I understand that it's the cf. of the room times a minimum of 4 divided by 60 for the formula.

My room is 1206 cf. so according to the formula;
air circulated 4x per hour = 80 CFM
air circulated 6x per hour = 120 CFM

All of the equipment will be in the room and it will hold up to 6 people. Does heat produced hold any relevance when calculating proper CFM for an enclosed HT? How many CFM's should I shoot for?

At the very most, the room fully occupied will be producing 9170 btu's or heat.

Was considering this fan...too powerful? not powerful enough?

Thank you.

beenthere 04-13-2013 12:32 AM

Its not the cubic foot of a room that determines how much air it needs. Its the heat produced in the room, how much heat the room gains, and the temp of the air that is being put into the room that determines CFM.

So you have 6470 BTUs from equipment, and 2700 BTUs from people. What about heat gain through the walls.

Mijotter 04-14-2013 01:40 PM

Not much heat gain through the walls at all as it's 100% insulated and the room is surrounded by exterior foundation walls and an unfinished portion of the basement. What would be the proper CFM and amount of air exchanges per hour require for this room.

beenthere 04-14-2013 02:03 PM

From an A/C with a 20 degree cooler air temp enteing the room then the room is, about 300 CFM.

Mijotter 04-14-2013 02:09 PM

Oh wow. Is that even possible with a 6" flex duct? Would it cause a "wooshing" noise at the vent?

beenthere 04-14-2013 02:56 PM

It would take 4-6" flex ducts.

You have a 3/4 ton cooling load.

Mijotter 04-14-2013 03:12 PM

1 Attachment(s)
I'm sorry did you mean four 6" flex ducts? I plan on building 2 dead vents(1 for supply and 1 for return) for the room so as to isolate the theater vents from the rest of the duct work for sound isolation purposes. Here is what it looks like:

beenthere 04-14-2013 03:18 PM

Yes, four 6".

Or you can use a 1-10".

You would be better off just installing a ductless mini split. using ir for another room to cool the theater room, won't get you humidity control. So it won't be comfortable.

Mijotter 04-14-2013 03:31 PM

Well I've been told to use the fan I linked in the return and supply dead vent and just have them both run at the same time the whole time i'm down there. Would that work or still no. The adjacent room in the basement has 3 supplies and 1 return already from the main furnace and a dehumidifier.

What do you mean IR from another room? Infrared signal?

beenthere 04-14-2013 05:14 PM

LOL. "ir" was suppose to be "air".

The person who told you to just use that fan set up. How well does it work in their theater room.

All times are GMT -5. The time now is 05:44 AM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1