How to Estimate Drywall and Stud Partition Quantities
Introduction
A stud partition looks simple from the outside: a flat surface, a door opening, a coat of paint. Behind it sits a system of studs, track, boards, screws, tape and compound, and each of those is a separate order line. Estimating a partition by board area alone gets you the boards and nothing else, which is roughly 55% of the material cost.
This guide measures a partition properly: both faces, the stud and track that set the frame, the screws and compound that finish it, and the board type that the building regulation or the acoustic requirement imposes. Worked examples are given in metric and imperial.
What a partition actually consumes
For every square metre of finished partition, you need:
Boards on both faces, unless it is a lining to an existing wall
Studs at a spacing set by the board and the height
Track top and bottom
Screws, 30-40 per square metre of board
Joint tape and compound, for every joint
Filler and sealant, where the partition meets structure
Insulation, if acoustic or thermal performance is required
The single most common estimating error is counting one face. A 20 m² partition has 40 m² of board. That is not a detail; it is a 100% error on the largest line.
Board sizes and what they mean for waste
Plasterboard is sold in sheets of 1,200 mm width and lengths of 2,400, 2,700, 3,000 and, in some markets, 3,600 mm. The sheet length should match the room height, because a sheet that spans floor to ceiling removes the horizontal joint and speeds up the taping.
Board size
Coverage
Typical use
|---|---|---|
2,400 × 1,200 mm
2.88 m²
Rooms up to 2.4 m
2,700 × 1,200 mm
3.24 m²
Standard 2.4-2.6 m ceilings
3,000 × 1,200 mm
3.60 m²
2.7-2.9 m ceilings
3,600 × 1,200 mm
4.32 m²
Tall spaces, fewer joints
Waste depends on the match between sheet length and room height. A 2.7 m partition with 2.4 m sheets wastes 300 mm off every sheet, which is 11% before any cutting. The same wall with 2.7 m sheets wastes almost nothing.
Measure both faces and every opening
Partition area for boards = (length × height) × 2 faces, or once if it is a single-sided lining.
Deduct openings above about 1 m², and add the reveals: a 100 mm stud wall has 100 mm of return at each side of every opening, which is 0.2 m² per door of 2.1 m height.
Worked example. A partition 7.5 m long and 2.7 m high, with two doorways of 0.9 × 2.1 m:
Wall area one face = 7.5 × 2.7 = 20.25 m²
Deduct two doors = 3.78 m²
Reveals to add = 2 × (2 × 2.1 × 0.1) = 0.84 m²
Net one face = 17.31 m²
Both faces = 34.62 m²
Worked example, imperial. The same partition as 24 ft 7 in × 8 ft 10 in: 216.9 sq ft one face, less 40.7 sq ft of openings, plus 9.0 sq ft of reveals = 185.2 sq ft; both faces 370.4 sq ft.
Boards to order
Sheets = area ÷ sheet coverage, then add waste.
For 34.62 m² using 2.7 × 1.2 m sheets at 3.24 m²:
34.62 ÷ 3.24 = 10.7 sheets
Add 10% for cutting and breakage: 11.8
Order 12 sheets
If the same wall uses 2.4 m sheets, the sheet count rises to 12 plus waste, and every sheet is cut down, which adds labour as well as material. Match the sheet to the ceiling height whenever you can.
Studs and track
Studs are spaced at 400 mm or 600 mm centres. The choice depends on the board thickness, the height of the partition and the load it carries: 600 mm is standard for a 12.5 mm board in a domestic partition; 400 mm is used for tall partitions, tile backing, heavy shelves or higher acoustic performance.
Number of studs = (length ÷ spacing) + 1, plus one at each side of every opening.
For the 7.5 m partition at 600 mm centres: 7.5 ÷ 0.6 = 12.5, so 13 bays, which needs 14 studs, plus 4 for the two doorways, so 18 studs.
Stud length equals the floor-to-ceiling height less the track depth allowance, typically 2.7 m minus 5 mm. In imperial markets, studs come in standard lengths and are cut on site.
Track is the same length as the partition, top and bottom, so 15 m of track for a 7.5 m wall, and remember that track and stud are different products even though they look similar.
Screws, tape and compound
Screws: 30-40 per square metre of board, so 34.62 m² needs roughly 1,100-1,400 screws. Buy boxes of 1,000 and expect to open a second.
Joint tape: the length of every joint. Two faces of a 7.5 m wall with 2.7 m sheets have vertical joints every 1.2 m and a horizontal joint at the sheet ends. Allow 1.2-1.5 m of tape per square metre of board.
Jointing compound: about 0.5 kg per square metre for a three-coat finish, so 34.62 m² needs 17-18 kg, which is two 12.5 kg bags with a little spare.
Corner beads: at every external corner and every door reveal, in linear metres.
The finishing materials are cheap individually and consistently underestimated as a group.
Board type is a specification decision
Standard board for dry domestic rooms
Moisture-resistant board in bathrooms, kitchens and anywhere with steam
Fire-resistant board for compartment walls, garages and boiler rooms
Acoustic board, denser and often combined with insulation, for party and bedroom walls
Impact-resistant board in corridors, schools and commercial space
The type changes the price per sheet by 20-60%, and it changes the fixing pattern and sometimes the stud spacing. An estimate built on standard board for a bathroom will need revising, and the revision usually arrives after the boards are on site.
Insulation and acoustic performance
A partition with insulation in the cavity performs far better acoustically than an empty one. Mineral wool slabs at 25-50 mm thickness fill the stud bay, measured as the area of the partition, not both faces.
For a domestic partition between bedrooms, 50 mm acoustic insulation plus a double layer of board on one face is a common specification. That doubles the board quantity on one face, which is exactly the kind of change that an area-based estimate misses.
Access, sequence and productivity
A two-person gang fits and finishes 25-35 m² of partition per day in a straightforward room with materials to hand. Output falls with:
high ceilings, which need trestles or towers
many openings and returns
double-layer or fire-rated systems
working around live services
a building that is not weathertight, because boards absorb moisture
Time is not a material line, but on a partition it is often more than half the cost, so an estimate that assumes a clear room and a wet building will understate labour.
Lining an existing wall is a different takeoff
A drylining system fixed to an existing masonry wall is one face of board on battens or adhesive dabs, not a partition. The board area is the wall area once, the framing is battens rather than studs, and there is no track.
The arithmetic difference is large: the same 20 m² of wall is 20 m² of board as a lining and 40 m² as a partition. Confusing the two doubles or halves the order depending on which way you get it wrong.
Lining also brings a damp risk that a partition does not: a batten or dab fixed to a damp wall traps moisture behind the board, which is why a vapour check or a drained cavity is specified in some constructions. If the specification includes a membrane, that is another line in the estimate measured in square metres.
Fire, damp and the details that change the order
Three specification items quietly change both quantities and cost:
Fire resistance. A 30-minute partition is typically a single layer of fire-rated board; 60 minutes usually needs a double layer or a specialist system, which doubles the board on that face and adds staggered joints, more screws and more compound.
Moisture. Bathrooms and kitchens need moisture-resistant board, and the jointing compound and screws should be the same grade. Using standard screws in a wet area is a corrosion failure waiting two years.
Acoustic separation. Party and bedroom walls often need a resilient bar or a twin-stud arrangement. Both add framing components that are priced per linear metre and are absent from a simple stud estimate.
None of these is optional once the specification names them, and all of them are cheaper to price before the boards are ordered than after.
A short takeoff checklist
Confirm partition length, height and the number of faces
List every opening with its size, then add the reveals
Choose the board type and thickness from the specification
Choose the sheet length closest to the room height
Set the stud spacing, then count studs as bays plus one, plus openings
Measure track as length × 2, and add deflection heads at structural soffits
Allow 30-40 screws, 1.2-1.5 m of tape and 0.5 kg of compound per square metre of board
Add insulation, vapour check, resilient bars or a second layer if specified
Add 10% waste, and 15% where sheets must be cut down from a longer length
Work through that list once and the order is complete. Skip step 2 or step 6 and the shortfall arrives on the day the boards go up.
Cost per square metre, and how to compare quotes
Drylining quotes are usually expressed per square metre of partition, sometimes per square metre of board. Both are legitimate, but they must be compared on the same basis.
Normalise the quote to cost per square metre of finished partition, both faces, including frame, board, insulation if specified, screws, tape, compound and finishing to paint-ready. Then check three exclusions: whether the door openings are formed and lined, whether the junction sealant is included, and whether the boards are a specified type or whatever is on the van.
The difference between a cheap quote and an accurate one is rarely labour. It is usually board type, layer count and whether the wall is actually finished to paint standard or merely boarded.
Movement, settlement and the cracks that follow
A partition is a light, flexible element in a building that moves. Two details prevent most of the cracking that appears in the first year:
Leave a gap at the head. Boards should stop 5-10 mm short of the structural soffit, with the gap sealed. A board forced tight against a concrete soffit will crack when the slab deflects.
Do not fix boards hard at every edge. Boards need to move with the frame. Screws over-driven into the board face break the paper and create a crack path; screws set flush and just below the surface do not.
These are construction details, but they belong in the estimate as much as in the workmanship, because the cost of returning to a cracked wall is a cost the original estimate claimed to have covered.
Frequently asked questions
How many boards do I need for a 20 m² partition? Both faces is 40 m². At 3.24 m² per sheet, that is 13 sheets plus 10% waste, so 15.
What stud spacing should I use? 600 mm for standard domestic partitions with 12.5 mm board; 400 mm for tall walls, tile backing, heavy loads or better acoustics.
How many screws per board? Roughly 30 per 2.4 m² board, so 12-15 per square metre, more along edges and at every stud.
Does a partition need insulation? For acoustic separation between rooms, yes. For a single partition in an open plan space, it is optional but improves sound noticeably.
Can I tile onto plasterboard? Light tiles onto moisture-resistant board, with the weight checked against the board's limit. Heavy tiles need a backer board.
Why is my joint showing after painting? Usually too little compound, no tape, or movement at the junction with the structure. A joint that is taped, filled and feathered properly does not telegraph through paint.
Estimate it with FRELUX
The FRELUX drywall and partition calculator counts boards by sheet size, studs by spacing, track, screws and compound, and prices the system from your market's price book. Enter the room height and it will tell you which sheet length wastes least.