Stud Spacing Calculator

Divide the wall length by the spacing to get the number of gaps, then add one. A 4,800 mm wall at 400 mm centres has twelve gaps and needs thirteen studs.

Spacing measured from the centre of one member to the centre of the next, rather than the clear gap between them. It is the standard convention because it makes sheet materials land on studs regardless of stud thickness.

Because standard sheet materials are 1,200 mm wide, which divides evenly by both. A non-standard spacing means cutting every sheet to land on a stud, which wastes material and time.

No — it counts the field studs at the stated spacing. Corners need additional studs to provide a fixing for the intersecting wall, and openings need trimmers, cripples and a header.

It depends on the load, the wall height and the stud section, which is set by a span table in local codes. Wider spacing also makes plasterboard more likely to show fixings and deflection.

Horizontal members between studs, which stiffen the wall and provide fixings for heavy items. They are usually required at intervals by code for walls above a certain height.

With additional studs or a corner post arrangement, so both walls have something to fix plasterboard to and the corner can be insulated. Two studs nailed together is the old approach; three-stud and California corners insulate better.

The beam over an opening that carries the load around it. Its size depends on the span and the load above, which is a code and span-table question rather than a rule of thumb.

Short studs above a header or below a sill, continuing the stud spacing so sheet materials still land on a fixing. They carry little load and they are what keeps the layout regular.

Non-load-bearing partitions can often go wider, and 600 mm is common. Sheet material still has to land on studs, so the standard spacings persist for that reason alone.

A stud detector, or tapping and looking for fixings in the skirting. Electrical outlets are usually fixed to a stud on one side, which gives a reference to measure spacing from.

It comes from the linings rather than the timber — the plasterboard type, thickness and number of layers. A rated wall is a specified assembly, and substituting any part of it invalidates the rating.