I am in the process of building a recording studio in my basement. One room (my Vocal Booth) is approximately 14'x7'. My control room is approximately 19'x12'.
What I need to know is where is the best position for the air return vents to be located in each room? Near the floor or ceiling? Presently, both of my supplies are mounted in the ceiling.
The Vocal Booth (as small as it is) may have up to 6 people in it at one time. With this many people in this "small" room, heat will be generated substantially. The Vocal Booth has one 7" return in it and the control room has one 8" return in it. The returns are running back to, and are tied into my basement Air Handler return. The basement has it's own independant HVAC system (there is one Air Handler/Heat Pump system for each level of the house (3 levels).
The Vocal booth has one 8" supply as does the Control Room.
Any and all help will be appreciated!
You'll want a NC(Noise Criteria) of < 25,suitable for acute pickup of all sounds,I'd think.
Look for commercial grilles ,size by cfms(air quanity),and NC.
You'll want to increase the return size ,before getting to the grille to slow the air down.If it's metal duct it may still be noisey.
Sounds like you may not have enough cfms(air flow),for the number of people,can't tell for sure.
Thanx for the reply!
All of the duct lines are insulated flexduct. The supply for each room is coming from a ductboard trunk from my Air Handler. The supply flexduct lines for each room are approximately 8 ft. in length (from the trunk). Both of the returns are flexduct directly from the Air Handler.
If the verdict is to place the return registers near the FLOOR, my plan was to line the 2x4 frame cavity with ductboard to help slow down air movement from the register to an elbow at the top of the ductboard-lined cavity which connects to the flexduct. This would be done for both returns.
If the verdict is that the returns should be placed on the CEILING, then it's just a matter of elbowing from the flexduct to the ceiling register.
I'll be contacting Hart & Cooley to get their recommendations on the register/grill that would be appropriate for me. (Thanx for the link!)
I still need info as to whether the RETURN registers/grills should be placed near the ceiling or near the floor.
IMHO,you can place them high or low,little to no difference,as stated in Manual D,the industry standard.
However since the space is small,I'd say,have the supply in the ceiling ,as you do,with the return in the wall low ,directly under the supply,to mix the air in the space.this is assuming a curved bladed supply,that throws the along the ceiling.
it would be best if the supply was on the 7' wall ,throwing the air the length of the room.If it's not you should use a 3-way supply grille .
Should I oversize the SUPPLY duct before it reaches the register/grill? Should I even oversize the Supply register/grill?
Supply griles are sized by cfm required,pressure loss,and "throw"(how far the air will travel after leaving the grille).You want the throw to be minimum of 75% of the distance to the oposite wall,and maximum of the distance to the wall.
Larger will reduce the presure loss and any noise,but the throw will be reduced as well.
So yes larger ,but not too large,try the hart and cooley site,for the details on grilles that are similar to wht you have ,or buy that brand.
Probelm is, you probably don't know, the actual cfms(cubic feet of air per minute).
7" likely 120 to 155 cfms
8" likely 145 to 200 cfms