adding vent to current HVAC system
I am finishing an attic above a garage for another bedroom. There is an HVAC unit upstairs for the bedroom and media room already there. I would like to vent this new room with this unit. It is right next to the new room. How do you and where do you cut into the current ducts to add the addional vent? Is there is website that gives pictures or explanations on how to do this. I am assuming it is not very difficult.
You cut into the supply trunk for additional "hits". Assumming you have the room / access, purchase a 6" starter collar, and trace out the circle on the supply duct. When you have the circle cut out, you simply bend the tabs back on the collar, and they hold it in place. Then you can install 6" ridgid circular pipe, or for easier installation in tight spaces use insulated flex pipe. The flex pipe is more expensive, but saves time and requires virtually no fittings.
Along with the start collar, you will need a register 'boot' if you are using floor registers. These to can be purchased at home centers. If you cannot hard pipe to the floor boot. As a last resort I would use flex. It is insulated but the airflow lose incountered with this is stagering.