How many ducts per room

I didn't push the issue initially because I didn't necessarily want floor vents. Downstairs we have floor vents in hardwood and that is perfect. But with tile and carpet, floor vents wind up being metal which is less than ideal. Now you could do some in the ceiling and some in the floor but that loses any efficiency benefit and the longer duct runs actually cost some efficiency and cost money initially.

Insulating the floor is not an issue. I have insulation between basement and 1st floor and also ductwork running there. As an aside, insulating the floor does not help a lot with sound. Insulation is a pretty bad sound barrier anyway but it does close to zero for foot stomps which is the main issue in the basement.

Builders push insulation for sound because it is so cheap and it gives them something to do easily. But if you want to cut sound significantly, you have to spend some money. We may do more sound proofing over the garage since we have a bedroom there. What I would do is a second layer of drywall with a sound barrier glue used inbetween. R is a little better at sound and is what you get if you walk into Lowes and look for sound insulation.

Cellulose is better still. But like I said, nothing is really any good in that category. If you put HVAC equipment in the attic that space should be included in the conditioned envelope of the house, ie it should be heated and cooled and insulation should be in the attic rafter framing instead of the attic floor framing.

Renovator - thanks for the input. We are doing ceiling vents upstairs after all. Met with everyone today and moved a few things around a bit so it all works. Our air handler is in the attic.

After lots of research, it doesn't seem to make financial sense in our climate to do a sealed attic, at least with the size of house we are building. Foaming the rafters was 7, and the payback was way too long to be fiscally sound. Indem Sie weiterhin auf der Website surfen bzw.

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Please stop, and seek professional guidance. The number of registers don't correlate to duct size, or home size, or unit size. I don't really know where to even begin explaining it because there is really no point, just stop, please. Basic rule of thumb is do load for the room , say the room calls for a 10X15 grill, well you dont want that large of a stupid grill in the room, so spilt the air , maybe you end up with 2 6X8 grills, these are not hard numbers but just examples, then you may have raised ceilings in a large living room, look at the layout of the room and figure out your load then determine by the room layout ceiling height and so forth to determine number of grills and best location, there is no exact science to it just basic applied theory.

Jason J Saylor Johnson Controls "You will encounter many distractions and many temptations to put your goals aside: The security of a job, a wife who wants kids, Whatever. But if you hang in there, always following your vision, I have no doubt you will succeed. There are plenty of ways to manipulate the number of and sizes of registers to meet the air flow requirements and it all starts with the manual J calcs. Choose which is larger of your HF or CF for room design cfm then you use the ductulator to choose size.

Is is open? Meaning is there a dresser of bed or something on front of it? The principal of a heating system is that the furnace fan does 2 things, it pushes conditioned air hot or cold into the rooms at the same time it sucks out the "used" or unconditioned air through the return vent. The air must circulate in order to properly heat or cool.

As for balancing the ducts, this is one of the most important things a homeowner can do himself and one of the most overlooked things.

Basically you open and close dampers to direct more or less air to the outlet vents. This controls the amount of air going into each room. Just closing the vent in the room is not good enough because you just create a back pressure in the duct work. You can search duct balancing and get tons of hits. There are even companies springing up that will do this for you because it has become known that people are not doing it.

Many furnace installation companies have added this as a service for a fee as well. There was one main duct that run north to south, feeding all the rooms. As it were, the rooms to the south had much higher airflow because the main run was shorter and there were less takeoffs from the shorter run.

I played around with the damper on the main duct to try and divert more air to the north side of the house and it was slightly effect. The master bedroom was situated on the north side of the home and was fed by the takeoff at the end of the main supply. I could never get enough air to that room. It is the biggest room in the house and has the least amount of airflow. Needless to say, it is hot in the summer and cold in the winter.

The master bedroom in my current home is situated on the west side and is above the garage. I have no issues thanks in part to the room having 3 supplies along the outer wall.

This is the way ducting should be constructed. The bigger rooms should have extra supply ducts. If that does not work, then other avenues need to be researched and tried. For example, one AC duct in a bedroom may be adequate, but in the great room or living room area, the room's size alone may call for more than one register. HVAC contractors perform a variety of calculations to engineer a room's airflow through the air conditioning or heating system. Contractors use a formula to determine how many times air enters a room in a hour through the HVAC system, measured in cubic feet per minute multiplied by 60 to translate it to cubic feet per hour.

This helps them to correctly balance the airflow for the room with the proper duct and register size for the home and AC unit. Using the standard airflow change table, a bedroom should change its airflow five to six times per hour, while a bathroom generally requires six to seven changes per hour.