I've met with a couple HVAC contractors to get their opinion and a quote for heating/cooling a dedicated home theater I'm about to start construction on. One has been good, but has proposed a solution that I think might be overkill and the others didn't give me enough confidence in their understanding of the issues at hand to properly handle the job.
I found this site on a quick google search and figured it would be a good place to ask for some opinions and/or some suggestions that I can present to some local HVAC contractors.
I live in Northern Ontario -- hot & humid during the summer months and cold during the winter months. The house is about 3000 sq. feet and has an existing gas furnace with adequate heating/cooling capabilities. The house also has a full HRV system. The theater I'm planning on constructing is going to reside in the basement which was partially finished when I took possession a few months ago (I have since gutted it). The room that existed where the new theater will be built had 2 6" supplies coming off two plenums and had a cold air return which was decent in size (it used the cavity between two studs - 16 o/c with a wall plate near the floor).
The theater I am about to start construction on will be a dedicated space and will have extensive sound proofing/isolation measures. The theater room will be built as tight as possible (2 layers of 5/8 drywall) with acoustical sealant on every joint. The idea is minimize the amount of noise coming in and out of the space. Adjacent to the theater will be an equipment room that will house a fairly substantial array of gear for the theater and for a distributed a/v setup for the rest of the house. This room will be built in the same fashion as the theater -- as tight as possible.
Here is a floor plan showing existing duct locations and proposed new runs:
Larger version here
My "Plan" thus far
After some extensive research and consultation with a few builders of dedicated theaters, it has been suggested that I do the following:
- Convert the existing 6" ducts (which are currently rigid) to 6" flex
- Bring the two flex ducts through the ceiling near the edge of the wall exterior wall
- build a sealed soffit around the permiter of the room (perhaps 5" tall and 12-14" deep) and box/seal out a portion of it (perhaps 3-4 feet in one direction) where the flex lines enter and install a vent on the underside of the soffit. Reason is to try and make it difficult for sound to enter/escape the room.
- Instead of tapping into the existing cold-air-return system, build a "dead-vent" instead which would simply exhaust air from the theater into an adjoining space where a regular cold-air-return would be present. More info on the design of the dead-vent can be found here: http://www.soundproofingcompany.com/...the-dead-vent/
- Install a dedicated Mitsu Mr. Slim split for cooling the space as required
- Install two vents in the ceiling of the equipment room and use an inline Panasonic fan to exhaust the warm/hot air into the adjacent hallway
- I simply want to ensure that I'm exchanging enough air in the theater space. I'm pretty confident that with the 9000 BTU Mr. Slim split that cooling won't be a problem, but I want to make sure enough fresh air makes its way into the space.
- I want to make sure its ok to use the "dead-vent" instead of tapping into the existing (and loud) cold air return system.
- I'm not sure how to bring fresh air into the equipment room.
Any suggestions or discussion would be helpful. It would allow me to point any local hvac contractors to this post with hopes of at the very least starting a discussion about the various options.