Air Ducts Between Floors

Area through this access hole.

Air ducts between floors.

Without a return air duct the air would not properly circulate and your energy costs would rise. Section m1601 1 1 above ground duct systems. If the supply ducts are high or in the ceiling then the return air ducts or grills should be low on a wall. The warm air will offset any cold air entering around the window and reduce condensation or frost on the window.

Section r403 2 1 insulation prescriptive. This article describes heating and air conditioning ducts that have been placed in or beneath concrete floor slabs. A return air duct is what carries air back to the furnace after it is dispensed throughout the home through the supply duct. It turns out that the air conditioning ducts in that space are covered in condensation which is.

Return air grille with a piece of sheet metal attached to the back of the grille that has been painted flat black. Hvac ductwork in floor slabs. Functional troubles such as lack of air flow or collapsed ductwork and environmental problems such as. We ve recently had a slight moldy smell and water on the 1st floor ceiling.

Stud wall cavities and spaces between solid floor joists cannot be used as supply air plenums. Return air ducts usually use ceiling joist spaces as the actual duct which then runs back toward the furnace. Section r403 2 3 building cavities mandatory. If the supply ducts are in the floor then the return air should be located up high.

This pulls the air across your body. The opposite is true for ceiling ducts which should be placed as far away from windows as possible so that heat warms the room and not the window. We have a 2 floor house built in 1978 in the dc area which is hot and very humid in the summer. Hvac air ducts located inside concrete slab floors invite a surprisingly broad range of building problems that fall into two broad categories.

Floor ducts placed below a window give better results. This size fits just between most floor joists. Building framing cavities cannot be used as supply ducts or plenums. When the work is completed install a 14 in.

One of the upstairs closets has a hatch in the floor that lets us look in between the lower ceiling and the upper floor.