Furrdown
A framed drop below the ceiling that hides ducts or pipes.
Quick Answer
A furrdown, also spelled furr-down or fur-down, is a framed section that drops below the main ceiling to enclose ducts, pipes or other services. A bulkhead is the same kind of lowered box. Estimators take it off as linear feet of run, then count the framing, board and finishes by the girth of the box.
The Full Picture
A furrdown is a lowered portion of ceiling or a box built down from it. It is normally framed with wood or metal studs and covered with drywall, and it hides ducts, pipes, conduit or structure that cannot go in the ceiling cavity. Bulkhead is the term many crews use for the same thing, though a bulkhead can also mean a soffit at a ceiling height change or a wall at a stair or shaft. In residential work, a fur-down duct chase is often used to bring ducts inside the building's thermal envelope, and the Building America Solution Center says the top of such a chase should be sealed from the unconditioned attic above, with the chase ceiling drywall extended over the adjoining top plates.
Furrdowns show up on reflected ceiling plans and building sections, and the dimensions come from the section details. The size is set by the mechanical or plumbing design, so the structural, architectural and mechanical sets may all need to be read to find every one. The estimator measures the run in linear feet, then records the drop and the width, because those two numbers determine the framing and the board. Furrdowns also commonly appear in corridors, over kitchen hoods, around plumbing risers and along exterior walls.
Where the takeoff goes wrong is in splitting the scope. Framing, drywall, finishing, paint, insulation or fire-blocking, and access panels may belong to different subcontractors. A furrdown with a rated assembly can also change the board type and the number of layers. The corners are another cost, because a box has an outside corner on each bottom edge, so corner bead length rides on the LF.
Coordination is the large risk. If the mechanical contractor's ductwork is larger than the furrdown shown, the box changes after bid. Carry a note that the sizes were taken from the architectural details and need to be checked against the mechanical shop drawings.
Real Examples
Common Misconceptions
People assume: A furrdown is just the drywall on the ceiling.
Actually: It is a framed box with its own studs or tracks, board, corner bead and finishing. The takeoff has framing, board and finish lines, and often insulation, blocking and an access panel as well.
People assume: Bulkhead and furrdown always mean the same thing.
Actually: Trades use them loosely. A bulkhead can also be a ceiling step or a wall at a shaft. Check the detail before you price it as a furrdown.
Does MeltPlan Solve This?
Partially — adjacentFurrdown lengths, drops and widths are measured from the reflected ceiling plans and building sections, and MeltPlan's takeoff service covers that measuring: AI pulls quantities from plans and US-based experienced estimators review and adjust them. Matching sizes to the mechanical shop drawings and deciding the assembly stay with the estimator.
Get ceiling soffits and bulkheads measured from your plans →Frequently Asked Questions
What is a furrdown in construction?
A furrdown is a framed drop below the ceiling, covered with board, that encloses ducts, pipes or other items. It is also called a bulkhead or dropped soffit, depending on the trade and the region.
Where do you find furrdowns in the plans?
Look at the reflected ceiling plans, building sections and wall sections for the drop and width, and at the mechanical and plumbing sets for what the box encloses. Dimensions are rarely on a single sheet.
How do you measure a furrdown for drywall?
Multiply the girth of the box, which is the sum of the sides and the bottom in feet, by the length. Add fascia or return sections at the ends, and deduct nothing unless there are large openings.
Does a furrdown need air sealing?
In homes with a duct chase below an attic, the Building America Solution Center says the top of the chase should be sealed against the unconditioned space above. Specs for other buildings vary, so check the details.