Making a stud-partition wall is the easiest way to divide a room into two: you can construct a plain wall or add a doorway, serving hatch or glazed area to ‘borrow’ light from an existing window. You can build the partition directly on to the floorboards, or on to the joists below so that the flooring will be independent of the partition. The sides of the partition can be set against the plaster surface or set in channels to provide a better fixing to the masonry and make any unevenness easier to fill.

With chalk, mark the width of the sill for the new wall on the floor, using the sill member — a length of 100 x 50mm (4 x 2in) sawn softwood — as a guide to draw the line. Continue the guidelines up the walls at each side, using a spirit level and straightedge or a plumb line and bob. Make guidelines on the ceiling by snapping a distinct chalk line on to the surface with a taut string (1).

Spacing the studs

Lay the sill and head members together with their face sides uppermost. Mark the position of the studs at 400mm (1ft 4in) or 600mm (2ft) centres, working from the middle. Square the lines across both members, using a try square (2). Use the 400mm (1ft 4in) spacing to support thin board materials

and 9.5mm (3/8in) thick plasterboard, and the 600mm (2ft) spacing for 12.5mm (1/2in) plasterboard and tongue-andgroove (T&G) boards.

Marking out a doorway

If you require a doorway in the wall, make an allowance for the opening. The studs that form the sides of the opening must be spaced apart by the width of the door plus a 6mm (I/4in) tolerance gap and the thickness of both door linings. Mark the width of the opening on the head plate, then mark the positions for the studs, working from the opening. Take the dimensions for the two sills from the head and cut both plates to length (3). The door studs overlap the ends of the sills, which must be cut back to allow for them.

Secure the sill to the floor on each side of the door opening, using 100mm (4in) long nails or 75mm (3in) long No10 countersunk woodscrews. Use the head plate as a guide to keep both parts of the sill in line. Prop the head plate against the ceiling on its line (4) and check the stud marks are true with the sill, using a plumb line. Nail or screw the head plate to the joists.

Measure the distance between the head and sill at each end and cut the outer wall studs to length: they should be a tight fit between the sill and head plate. Drill and plug the walls if you are fixing the studs with screws, or use 75mm (3in) long masonry nails.

Fixing door studs

Cut the foor studs to fit between the  head plate and floor. Wedge them in place, but do not fix them yet. Add together the door height and the thickness of the head lining, plus 9mm (3/bin) for tolerance, then mark the position of the underside of the door head on the edge of one stud. Hold a spirit level on this mark and transfer it accurately to the other door stud.

Fixing the door head

Remove the studs, then mark and cut a 12mm (1/2in) deep housing to receive the 50mm (2in) door head. Reposition and skew-nail the door studs to the head plate and dovetail-nail into the ends of the sills. Locate the door-head member in its housing and dovetail-nail it through the studs (5). Fit a short stud between the head plate and door head.

An alternative method for fixing the door studs is to cut them to the required door height and double up with a stud between the sill and head plate.

Support the door head and nail it to the top of the door studs. Cut a short length of studding to fit vertically between the centre of the head plate and door head. Secure in place by dovetail-nailing. Make sure when nailing all the parts together that their faces are flush.