Stud Wall Calculator – Timber, Plasterboard and Screws
Enter the wall size and we'll work out the studs, plates, noggins, plasterboard, screws, tape, skim and insulation — with a cost estimate.
Stud Wall Calculator
You need
10studs
3.6m × 2.4m wall at 400mm centres
- Head & sole plates
- 7.2 m
- Noggins
- 3.6 m
- Plasterboard sheets
- 7
- Drywall screws
- 210
How we worked this out
Your shopping list
10 × 2.4m lengths of CLS 38 × 89mm for studs
10 studs at 400mm centres.
£65.00
4 × 3.0m lengths of CLS 38 × 89mm for plates and noggins
7.2m of head and sole plate plus 3.6m of noggins.
£32.00
7 × 2400 × 1200mm plasterboard sheets (12.5mm)
17.28 m² of wall face, plus 10% waste.
£77.00
1 × Tubs of 1,000 drywall screws
About 210 screws at 30 per sheet.
£14.00
1 × Rolls of joint tape (90m)
Scrim or paper tape for the joints and internal angles.
£6.00
2 × 25kg bags of finish plaster
About one bag per 10 m² of skimmed face.
£24.00
2 × Rolls of acoustic mineral wool
8.64 m² between the studs at 5.7 m² per roll.
£56.00
Stud wall quantities at 400mm centres, boarded both sides
| Wall size | Studs | Plates | Noggins | Plasterboard sheets |
|---|---|---|---|---|
| 2.4 × 2.4 m | 7 | 4.8 m | 2.4 m | 5 |
| 3.0 × 2.4 m | 9 | 6.0 m | 3.0 m | 6 |
| 3.6 × 2.4 m | 10 | 7.2 m | 3.6 m | 7 |
| 4.2 × 2.4 m | 12 | 8.4 m | 4.2 m | 8 |
| 5.0 × 2.4 m | 14 | 10.0 m | 5.0 m | 10 |
How this calculator works
A stud wall is a simple frame: a sole plate on the floor, a head plate on the ceiling, vertical studs between them and a row of noggins to stop the studs twisting. We work the studs out as wall length ÷ stud centres, rounded up, plus one to close the far end — a 3.6m wall at 400mm centres needs 10 studs, not 9.
Each doorway adds two extra studs (one either side of the opening) plus a head over the top. Plates are twice the wall length. Noggins are one row at mid-height, or two rows if the wall is over 2.7m tall.
Plasterboard comes in 2400 × 1200mm sheets — 2.88m² each. We take the wall face area, multiply by one or two sides, divide by 2.88 and add 10% for cuts. Screws run at about 30 per sheet, and finish plaster covers roughly 10m² per 25kg bag.
Worked example: a 3.6m × 2.4m partition
3.6 ÷ 0.4 = 9, plus one = 10 studs at 2.4m long. Plates are 7.2m and there is one row of noggins at 3.6m. Boarding both sides gives 3.6 × 2.4 × 2 = 17.28m², which is 6 sheets before waste and 7 sheets after — plus about 210 drywall screws.
In money, that is roughly £65 of CLS studwork, £40 of plates and noggins, £77 of plasterboard, £14 of screws and £25 of skim — about £220 before insulation, or £250 with acoustic wool. A joiner and plasterer would typically charge £600–£900 to build and finish the same wall.
Building it properly
Mark the wall line on the floor, then plumb it up to the ceiling with a spirit level or laser — it is very easy to build a wall that is 20mm out of plumb over 2.4m and only notice when the door will not shut. Fix the sole plate into the joists or the slab, fix the head plate into the ceiling joists, then cut studs a millimetre tight so they wedge into place.
Put extra noggins anywhere you will hang weight: a radiator, a wall-hung basin, a TV bracket, kitchen units or a handrail. It takes five minutes now and saves surgery later. Run any cables through drilled holes in the centre of the studs, never through notches at the edge, and use grommets so the cable is not chafed by the timber.
Board with the sheets horizontal if you want fewer joints, keep the edges landing on the centre of a stud, and leave a 10mm gap at the floor which the skirting will cover. Tape and skim, or tape and fill if you are going for a painted taped-joint finish.
Tips from the trade counter
- Buy kiln-dried CLS. Wet timber twists as it dries and pushes the plasterboard joints apart.
- Use acoustic mineral wool, not loft roll. The denser slab makes a real difference to noise through bedroom walls.
- Plan the door before the frame. Build the rough opening about 10mm wider and taller than the lining so you can pack it plumb.
- Stagger the board joints. Do not line up joints on both sides of the wall on the same stud; it is a sound path and a crack line.
- Order one extra sheet. Plasterboard damages easily at corners and the delivery charge for a single missing sheet is painful.
When a partition needs building control
A simple non-loadbearing partition in an existing room usually does not need Building Regulations approval. It does if the work affects a fire escape route, leaves a room without adequate light or ventilation, subdivides a room containing a boiler or stairs, or forms part of a loft or garage conversion. Fire-rated board and door specifications apply in those cases.
If in any doubt, a quick call to your local council's building control team costs nothing and is far cheaper than taking a wall back down.
Frequently asked questions
What spacing should stud walls be?
400mm centres is the UK standard and suits 12.5mm plasterboard. 600mm centres uses less timber but needs thicker board and feels flexible — stick to 400mm for anything you will hang things on.
What timber size should I use for a stud wall?
CLS 38 × 63mm (nominal 3×2) is fine for a short non-loadbearing partition. 38 × 89mm (nominal 4×2) is stiffer, gives room for insulation and services, and is the usual choice for walls over about 2.4m.
How many plasterboard sheets do I need?
A standard UK sheet is 2400 × 1200mm, which is 2.88m². Divide the area of each side by 2.88 and add 10% for cuts, then round up.
How many screws per plasterboard sheet?
About 30 drywall screws per sheet at 300mm centres on the studs and 200mm around the edges. A 1,000-screw tub covers roughly 33 sheets.
Do I need noggins in a stud wall?
Yes. One row at mid-height for walls up to 2.7m and two rows above that. Add extra noggins wherever a radiator, TV bracket, basin or handrail will be fixed.
Should I insulate a stud wall?
Acoustic mineral wool between the studs makes a huge difference to sound transfer between rooms, and costs very little. It is close to essential for a bedroom or bathroom partition.
Does a stud wall need Building Regulations approval?
A simple non-loadbearing partition usually does not, but it can if it affects a fire escape route, blocks a window that provides light or ventilation, creates a room without ventilation, or forms part of a loft conversion. Check with your council's building control team.