Building a Stud Partition Wall and Fitting Plasterboard

Dividing a large room, creating a utility space or building a small home office are all jobs for a stud partition: a light frame of timber or metal studs, faced on both sides with plasterboard. It is one of the most DIY-friendly structural-looking jobs in a house, but the word "structural" is the catch. Before you buy a single length of timber, you need to know whether the wall will carry any load, what is hidden in the floor and ceiling where it will stand, and whether the new room triggers building regulations. This guide covers those checks, then the build, then the board.

Step one: is this wall load-bearing, and what is in the way?

A new partition that you are building from scratch is non-load-bearing by design, meaning it carries only its own weight and what you hang on it. The trouble comes when it replaces or sits beside an existing wall, or is being built where the floor above relies on it. Never remove an existing wall on a guess. The Planning Portal's guidance on internal walls says you should not need planning permission for internal alterations, but removing or altering a load-bearing wall is a building regulations matter, and listed buildings need listed building consent for significant internal works. Approved Document A covers structure.

For a new wall, check three things:

• Above and below. Where does the ceiling joist run, and where does the floor joist run? A partition parallel to the joists but between them needs support from noggins or a floor joist strengthening. A partition across the joists is easy to fix. Lift a board if you cannot tell.
• Services. Cables, pipes and ducts in the floor and ceiling, and any heating pipes, can be in the way. Do not drill blindly. Check with a detector, and confirm the route of any circuits.
• Floor loading. A heavy block wall on a suspended timber floor is not a DIY decision, but a light stud wall is typically fine. A wall of studs and two layers of board is much lighter than masonry.

If you find asbestos-containing materials or are unsure about anything suspicious in older ceilings or textured coatings, stop and get it identified before cutting or drilling.

Do you need building regulations approval?

Often not for a simple non-load-bearing partition within a single dwelling, but several consequences can pull the job into scope. In England, adding a new room can affect means of escape from fire (Approved Document B), ventilation (Approved Document F), and electrical work (Approved Document P). Creating a bedroom out of an inner room, for example, can mean that the only escape route passes through another habitable room, which needs consideration. Dividing a space so that a room has no window or ventilation can fail the ventilation requirements. If you are adding sockets or lights to the new room, the electrical work has to comply with Part P. When in doubt, ask local building control before you start. Scotland and Northern Ireland operate separate building standards systems, so the document references here apply to England.

Timber studs or metal studs?

Both are acceptable. Many DIYers choose timber because they have the tools and know it, such as 75 x 50 mm or 100 x 50 mm sawn and treated softwood. Metal systems are sold with published performance data (fire, sound and height limits) for tested combinations of studs, boards and fixings. If you need a specific fire or sound rating, follow the manufacturer's tested system exactly, rather than mixing components.

Laying out the frame

1. Mark the line. Snap a chalk line on the floor, and use a plumb line or laser to transfer it to the ceiling. Check the corner angles with a tape (3-4-5 triangle).
2. Fix the head plate to the ceiling. Screw into the joists if the wall runs across them, or between them using noggins fixed to the joists if it runs parallel. Where the ceiling is plasterboard, never rely on the board alone.
3. Fix the sole plate to the floor. Screw into joists or use masonry fixings into concrete. Leave a gap at doorways, and cut out the plate after the frame is up.
4. Cut and fit the studs. Place vertical studs between the plates. In timber, stud centres of 400 mm are the traditional spacing, and 600 mm centres are used with thicker boards or where the board manufacturer allows; 600 mm centres work with 12.5 mm board in many systems, as long as board edges and joints are supported. Metal system manufacturers publish the spacing and the maximum wall height for each stud size, for example 70 mm studs at 600 mm centres in published single-frame systems. Follow the data sheet for your chosen system.
5. Add noggins. Horizontal timber pieces between studs support board edges, door frames and wall-hung items such as radiators, shelves and TV brackets. One row around mid-height is common for timber frames, and extra pieces go wherever heavy items will hang.
6. Frame the door. Use double studs either side of the opening and a head (lintel) piece above, all fixed securely and plumb. Ask the door-lining supplier for the rough opening size.

Plumb every stud and check the wall faces are in the same plane with a long straightedge; a wavy frame makes a wavy wall, and the plasterboard will not hide it.

Services and insulation

Run electrical cables and pipes before boarding. Cables through timber studs should run through holes drilled in the centre of the stud depth, not notches on the edge, and be protected where they are within 50 mm of the surface. Check the rules for cable zones with a qualified electrician, and notify or use a registered installer where Part P applies. A layer of mineral wool in the cavity improves sound insulation noticeably; it does not need to be thick, but it should fill the cavity without being compressed.

Choosing and ordering the plasterboard

Common boards in the UK are 2400 x 1200 mm, in 12.5 mm and 15 mm thicknesses, with 9.5 mm for lighter work and curved or retrofit applications. Standard board is fine for most dry rooms. Other types include moisture-resistant board for bathrooms and utility rooms, fire-resistant board where a fire rating is required, and acoustic board for sound control. Tapered-edge boards are for taping and jointing, and square-edge boards are for skimming. Ask your supplier which edge suits your finish.

To count boards, work out the area of each wall face, subtract nothing for small openings (the offcuts rarely fit anywhere else), and divide by 2.88 square metres per 2400 x 1200 board. Add 10 percent for waste.

Worked example (illustrative numbers): a partition 4.2 m long and 2.4 m high, boarded on both sides.

• One face: 4.2 x 2.4 = 10.08 square metres. Both faces: 20.16 square metres.
• Boards: 20.16 / 2.88 = 7.0 boards. With 10 percent waste: 7.7, so order 8 boards.
• Studs at 600 mm centres along 4.2 m: 4.2 / 0.6 = 7 spaces, so 8 studs, plus any door framing.

You can check your figures and the number of screws and metres of tape with the drywall and plasterboard stud wall calculator.

Fixing the board

1. Fit full-height boards. A 2400 mm board in a standard room is usually cut slightly short, about 10 to 15 mm, so that it does not jam at the floor; the gap is hidden by the skirting.
2. Stagger vertical joints. If you use more than one layer, offset the joints between layers so that no joint lines up with another.
3. Use the right screws. Drywall screws are used with a screw gun or a drill with a depth stop. Screws should be driven just below the paper surface without tearing it. Typical spacing is about 300 mm along the studs, according to board manufacturers' guidance, and closer at edges where specified.
4. Keep edges on supports. Every board edge should sit on a stud or noggin, and no screws closer than about 10 mm to a cut edge.
5. Cut with a knife. Score the face paper, snap the board back, and cut the rear paper. Use a keyhole saw for sockets, and mark out openings carefully after checking where the boxes sit.

Taping, jointing and finishing

For a taped and jointed finish, fill the tapered joints with joint compound, press in paper or mesh tape, and apply thin coats, sanding lightly between coats. For a plastered finish, use a PVA-based bonding agent where recommended and apply thin coats of finishing plaster. Fill screw heads. Allow each coat to dry fully before the next, and do not rush the drying with strong heat. Once the surface is dry, apply a primer or a thinned first coat of emulsion; the paint coverage calculator helps estimate volumes. Fresh plaster and joint compound are very absorbent, so a sealing coat evens out the finish.

Common mistakes

• Fixing the head plate to plasterboard only, so the wall pulls away from the ceiling.
• Forgetting noggins where radiators, wall units or TVs will hang, then having nothing solid to screw into.
• Running cables without protection or in the wrong place, creating a hazard when a picture hook is hammered in.
• Using the wrong board in damp rooms. Standard board absorbs moisture and softens.
• Over-tightening screws so that they break the paper, which reduces the holding strength.

When to call a professional

Hire a builder or structural engineer if the wall you are changing may be load-bearing, if you plan to create a bedroom in a house with an existing escape route, or if you need a rated fire or sound separation, for example between a flat and its neighbours. Use a registered electrician for any new circuits. This is general information, not professional advice, and your local authority building control team can confirm what applies to your project.

Sources

• Planning Portal: Internal walls
• GOV.UK: Approved Document A (Structure)
• GOV.UK: Approved Document B (Fire safety)
• GOV.UK: Approved Document F (Ventilation)
• GOV.UK: Approved Document P (Electrical safety)