What is GIB stopping?

What GIB stopping is

GIB is a brand of plasterboard so common in New Zealand that the name is used for plasterboard in general. Once the sheets are fixed, every join, screw head and corner still shows. GIB stopping hides them.

The stopper tapes each join, fills the screws and corners, then builds the joints up in thin, wider coats and sands them flat, so once the wall is painted you cannot tell where one sheet ends and the next begins. It is also called GIB plastering or jointing.

GIB fixing and GIB stopping are separate jobs

GIB fixing, also called lining or hanging, comes first: the sheets are cut, glued and screwed to the framing. Stopping finishes the surface afterwards.

Stopping hides small faults, but it cannot make a badly fixed wall flat. Sheets out of line, joints at the corners of doors and windows where the frame moves most, or screws driven through the paper all show up later as cracks and ridges. At IDW the same crew lines and stops, so the lining is done with the stopping in mind.

Why it matters in a timber-framed house

Most New Zealand houses are timber framed, and timber moves a little with the seasons. The joints take the strain. Tape bedded properly in compound ties the sheets together, and wide, feathered coats spread the stress, so cracks are less likely to open.

Light is the other test. Low sun or downlights across a wall pick out every ridge and sanding mark, and paint makes them more visible, not less.

Levels of finish, from 0 to 5

Stopping is specified by level, from 0 to 5. The level sets how many coats go on and how much sanding is done, so it is the first thing to check on a quote. We stop to Level 4 in most homes and recommend a Level 5 skim where the light, a dark colour or a gloss paint would show a Level 4 joint.

The GIB stopping process, step by step

This is the order of work on a Level 4 job. Knowing it helps you spot a rushed job.

• Check the board. Sheets firm and in line, screws set just below the surface without breaking the paper, nothing damp, and the house closed in.
• Tape coat. Paper tape is bedded in compound along each joint with no air trapped behind it. Screws get a first fill, internal corners are taped and external corners get a metal or plastic bead.
• Second coat. A wider coat fills the shallow recess along the tapered edges of the sheets and flattens the joint.
• Finishing coat. A thinner coat, spread wider again and feathered so its edges fade into the board.
• Sanding. Joints are sanded flat once dry, without scuffing the paper face of the board or cutting into the tape.
• Skim coat, for Level 5 only. A thin coat over the whole surface, then sanded again.
• Raking light check. A light held low along the wall or ceiling makes any ridge or hollow throw a shadow. Faults are filled and sanded before paint.
• Seal. Compound and board paper soak up paint differently, so a sealer or undercoat goes on first. Without it the joints can show through as patches of different sheen, known as flashing.

Sanding: where good stopping is won or lost

Sanding has to wait until the compound is dry right through, or the abrasive clogs and drags instead of cutting clean. Too little leaves edges that show as lines under paint. Too much scuffs the board's paper face or cuts into the tape, and both show through.

Sanding makes fine dust, so a careful crew contains it, protects floors and furniture, and cleans down before the sealer goes on.

Stopping compounds

Stopping compound, often called mud, comes in two broad types, and many jobs use both.

• Setting compound is mixed from powder and hardens by a chemical reaction, so humidity slows it far less. It is strong and suits the tape coat and deep fills, but it is harder to sand.
• Air-drying compound is usually ready-mixed and hardens as its water evaporates. It spreads and sands more easily, so it suits the later coats, but it dries slowly in cold, damp weather.

Drying times in Auckland

Each coat has to dry right through before the next. Compound coated over while damp keeps shrinking underneath, and that shows later as sunken joints and cracks. Auckland's humidity slows drying, and in winter it is worth allowing 24 to 36 hours between coats, which puts a three-coat Level 4 finish at about four to seven days including sanding.

Susan W, Google review: “2nd time using Hadi and his team at Interior Drywall Worx. Exemplary work between a team arriving as agreed, and courteously tidying up and returning on time once dry after the weekend to sand finish. A perfect job and price. Thanks again, would highly recommend IDW Ltd.”

What good GIB stopping looks like

Before the paint goes on, shine a torch flat along the wall. Good work has:

• Joints that throw no shadow, with no ridges, hollows or tape edges
• Tape lying flat, with no bubbles or blisters
• Screw heads you cannot see
• Straight, crisp corners with no cracks
• No sanding scratches or fuzzy, scuffed paper

How IDW stops a wall

IDW is one crew that lines, stops, plasters and paints, so if a joint shows there is no other trade to blame. Every wall and ceiling is checked under a raking light before it is painted, and one 5-year workmanship guarantee covers the work.

Hadi Haidary, who owns IDW, quotes and oversees every job himself. The free quote includes a wall health check, valued at $397, and the price goes in writing after we have seen the job. The price we quote is the price you pay. We plaster interiors only, across Auckland City, East Auckland, South Auckland, West Auckland and the North Shore. Call 027 521 7411 or 0800 33 1371.