What is dry lining, and how does it differ from plastering

Dry lining is a way of forming the inside faces of a building from plasterboard instead of wet plaster. The board is bonded to masonry with adhesive, screwed to a metal or timber frame, or fixed to studs and joists. The joints are then filled and taped, or the face skimmed, ready for decoration.

The UK code of practice is BS 8000-8:2023, Workmanship on construction sites. Design and installation of dry lining systems. BSI lists it as current. It covers dry lining with gypsum-based plasterboards in dwellings and other buildings, and it replaced BS 8212:1995 and BS 8000-8:1994.

The standard treats the lining as part of how the building performs. Its scope names separation, fire protection, stability, applied loadings, acoustics, thermal insulation and aesthetics.

It is called dry lining because the board is made in a factory and fixed dry, so very little water goes into the building. CITB's Go Construct gives the same reason: dry lining needs less water than plastering. Wet plaster is mixed on site, trowelled on in coats and left to dry.

That difference shows in the programme. A plastered wall holds water that has to dry out before decoration. Siniat says its direct bond lining reduces drying out time and speeds up internal fit-out. On a dry lined wall the wet materials are the adhesive behind the board and the compound or skim on its face.

The two trades still meet. A skim coat over plasterboard is a wet finish on a dry lined wall. Go Construct also notes that plaster can form mouldings such as cornices and ceiling roses, which board cannot.

There are four main ways to hold the board. It can be bonded to masonry on dabs of adhesive, known as dot and dab or direct bond. It can be screwed to metal channels fixed to the wall, or to a free-standing metal frame. On stud walls it is screwed to both faces of timber or metal studs.

Siniat's direct bond system sets dabs of bonding compound 250mm long and 50 to 75mm wide, at 600mm maximum horizontal and 300mm maximum vertical centres, with at least three columns a board. A continuous ribbon runs 50mm from the head and base of each board and around the wall perimeter for air-tightness. Knauf asks for a continuous band at floor and ceiling line to stop air leakage.

Direct bond suits level, sound masonry. Siniat rules out bonding to external solid walls and basements, and asks for a mechanical fix where moisture can reach the wall. Its lining on brackets and furring channel allows a cavity of up to 130mm. Its independent wall lining stands clear of the wall on its own studs.

Yes, in practice. Drywall is the North American name for gypsum board and for the trade that fixes it. In the UK the board is called plasterboard and the trade dry lining. Manufacturers here use both words. Siniat, for one, publishes its technical guidance as the Siniat Drywall Manual.

Plasterboard is a gypsum core faced with paper. Its product standard is BS EN 520, Gypsum plasterboards. Definitions, requirements and test methods. It covers boards made to take direct decoration and boards made to take gypsum plaster.

Most new homes use more than one board, picked room by room in the specification. Moisture resistant board goes where there is steam, fire board on a fire line, denser board where sound matters and insulated board on outside walls. Our guide to plasterboard fire ratings explains why the minutes belong to the whole wall.

A dry lined wall is finished in one of two ways. Tape and jointing fills and tapes the joints between boards and spots the screw heads, leaving the board face to take paint. A skim coat is a thin layer of plaster trowelled over the whole face. The specification decides which.

The board edge follows the finish. A tapered edge leaves a shallow recess along each long side for tape and compound. A square edge suits a skim that covers everything.

Siniat states its lining performance for imperforate, jointed systems. So a joint left open is a gap in the tested system as well as a mark under the paint.

Dry lining follows first fix and comes before second fix. The plot has to be weathertight, with windows and external doors in, and the first fix electrics, plumbing and ventilation carcassed. The boarders then close the walls and ceilings, and the second fix trades and decorators follow.

NHBC's best practice guide calls first fix the skeleton of the home before boarding and painting. It asks for windows and doors to give a watertight shell before other first fix work starts. Its judges mark dry lining on screw spacing, cuts around sockets and solid dabbing of boards.

Once a wall is boarded, what sits behind it is hidden. A back box, cable or pipe found missing afterwards means cutting the new board open and making good.

Dry lining is two jobs. Fixers, also called dry liners or boarders, measure, cut and fix the board. Tapers and jointers, sometimes called finishers, fill and tape the joints and sand them ready for paint. CITB's Go Construct describes the role in the same two parts, fixing and finishing.

Go Construct lists routes into the trade through college or an apprenticeship. The main apprenticeship it names is Interior Systems Installer, equivalent to NVQ Level 2 and lasting 24 months.

On a housing site the two are often let as one package. On JMC Drywall schemes the fixers and tapers answer to one named contracts manager, and each plot is photographed and signed off before it is offered to the client.