Cutting Plasterboard

Types of, uses and fixing sheets of Gyproc Plasterboard

After you have framed the wall you can start cutting plasterboard to size and fixing it in place, ready for the plasterers.

Provided all the studs are set out to the correct centres for the size of the boards and all the noggins are in place you should be able to board the wall really quickly.

Cutting plasterboard and the tools required

Plasterboard is cut to size by marking then scoring a line on the face side with a knife and snapping the board. Then you run the knife down the other side of the cut to sever the paper on the back. Luckily, you don't need any expensive tools to cut plasterboard. If it's a one off or you are not going to be cutting plasterboard a lot, then all you need is a plasterboard handsaw, stanley knife and a straight edge. I cut loads of plasterboard so i've got a Drywall T-square too. Using this tool means rather than measuring across the board twice and marking two lines to join up with a straight edge, you only have to mark the board once when cutting to length. Place the square up to the line and you can score it perfectly across the board. It saves loads of set out time and means I get perfectly square cuts every time.

If you are cutting plasterboard in an L shape, or need to cut a corner out of a board you will need to first cut one line (I normally do the shortest) with a handsaw and the other you can scribe with a knife and snap. Rather than buying a saw, I just use an old hand saw, cutting plasterboard with a new one will dull the teeth really quickly and you'll soon need another one.

How to cut holes in plasterboard

For perfectly round holes in plasterboard for things like spotlights and soil/waste pipes I use a plasterboard circle cutter like the one below. You can us a jabsaw like the other one pictured which is good for cutting for electrical cables etc.

Trimming the cut for a better fit

If you need to shave a bit of the board off, when scribing to an irregular shape for example you can use a surform, sometimes called a rasp. This tool works like a plane but has a replaceable blade that looks like a cheese grater.

How to fix plasterboard

Plasterboarding used to be called 'tacking', because boards were nailed to the studs or joists with tacks. These would often 'pop' the plaster off themselves if they weren't fixed properly and the board moved. Instead, boards are now screwed with drywall screws that almost eliminate this problem - provided they are not wound in too far. The screw heads need to finish flush with the surface of the board. If they are proud, not only are they not doing the job but the plasterer will catch and dent his trowel on them (then he'll probably moan like f#@k).

You can buy auto-feed screwguns and collated screws to fix plasterboard, special drywall screw guns or just use an ordinary cordless drill with a plasterboard bit that has a depth stop so you can quickly screw to the right depth each time.

Special drywall hammers are available for fixing plasterboard too. They have a large milled face for extra grip on the nail heads and also have a sharp flat claw that can be used like an axe to quickly and accurately chop holes in the plasterboard for boxes and cables etc. Click here for loads more info on hammers.

Tiling

Sizes available

There are varying thicknesses and specifications of boards available ranging from 6-25mm (1/4in to 1inch thick). The most commonly used boards on site are 2400x1200(8x4) and 1800x900(6x3) but longer boards are available for commercial projects. The 1800x900/600 boards are perfect for loft conversions because they can fit through velux windows.

Types of boards

Loads of different board properties are available, from acoustic to fire retardent. Some wall board systems can offer up to 4 hours worth of protection from a fire. 'Aqua boards' are also available that are mould resistant and can withstand high levels of moisture/ humidity, great for bathrooms etc.

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