Plasterboard Cost Calculator

When it comes to plasterboard, it can be difficult to estimate just how much plasterboard material you need for the job. Some people will want a full cost estimate, which includes the covering boards, the fittings, and the finish of the plaster in the room.

This calculator is effective as it can handle both elements of the job. Simply enter the details of the room, and then you will not only get a sheet count to take to a builders' merchants, but also a cost estimate for having the work completed for you.

Plasterboard Cost Calculator

How to Use This Plasterboard Calculator

First, enter the dimensions of your room. Try to make these as accurate as possible, as the calculator uses them to estimate both the cost and the number of plasterboard sheets needed.

Next, choose the board type and select whether the project will be completed as a DIY job or by a professional. From here, the calculator will estimate how many sheets are required, along with a rough cost figure that you can use as a starting point for budget planning.

Room Dimensions and Deductions

Getting the dimensions right is more important here than it would be for some other cost calculators. In this case, the measurements are used to create a more accurate plasterboard sheet estimate, rather than just a rough guide price.

Measure the length and height of each wall you are boarding, and then the length and width of the ceiling if this is included too.

You do not need to work out the exact area of every door and window individually. The standard approach is to deduct a flat allowance for each opening instead, typically around 1.5m²-2m² for a standard door and 1m²-1.5m² for an average window.

This is usually accurate enough for buying purposes and much faster than measuring every frame separately.

Board Size and Wastage

In the UK, a standard plasterboard sheet usually measures 2400mm x 1200mm. This is commonly called an 8x4 sheet and covers 2.88m² per board.

Larger sheets are available in 2700mm and 3000mm lengths, but these are typically used for larger rooms and higher ceilings. For most domestic jobs, 2400mm boards are the default choice.

This calculator rounds up to the nearest full sheet rather than providing a number that would be impossible to buy. For example, you cannot buy 0.4 of a plasterboard sheet.

It is also standard practice to allow around 10%-15% extra for wastage, cutting and shaping. Boards will rarely line up perfectly across a whole room, so allowing for wastage helps make sure you have enough material to complete the job.

Choosing the Right Board Type

Not all plasterboards are the same, so it is important to choose the right board type before buying materials.

• Standard Boards - Often called wallboard, these boards are most suitable for internal walls and ceilings in dry rooms. They are usually the cheapest option and are the right choice for most domestic jobs.
• Moisture-Resistant Boards - These boards are designed for bathrooms, kitchens and other areas with higher humidity. They are not fully waterproof, so they still need to be sealed properly in areas that may get directly wet.
• Fire-Resistant Boards - These boards contain additives that slow the spread of fire, although they are not fireproof. Building regulations may require this type of board in specific areas, such as between a garage and the main house or in some loft spaces.
• Insulated Boards - These boards usually include PIR or EPS insulation fixed to the back of a plasterboard sheet. They cost more than standard boards but can help improve the thermal performance of external walls.

DIY vs Hiring a Fitter

If you are completing this as a DIY job, you will need more than just plasterboard sheets. You may also need drywall screws or nails, scrim tape for the joints and joint compound to smooth the joins.

If you hire someone to complete the project for you, the price will usually cover both materials and labour.

However, it is important to check exactly what type of finish is included. Some quotes may only include boarding and taping, while others may also include skimming. These are priced differently because skimming adds a separate trade process, extra drying time and additional materials.

Why Board Type and Fitting Method Affect the Final Look

Plasterboard alone does not make up the finished wall. Once the boards are fitted, the surface will usually need either taping and jointing or skimming before it is ready to decorate.

Taping and jointing is usually quicker. The joints are filled with compound, covered with tape and sanded to create a smooth, paintable surface with less drying time.

Skimming involves applying a thin layer of wet plaster across the boards, usually around 2mm-3mm in depth. This is the traditional finish and creates a clean, smooth surface ready for decorating.

The key thing to remember is that plasterboarding a room and finishing a room are two separate stages. A room with boards fitted but no tape, jointing or skim is not ready to decorate.

Ready to Get a Quote?

Once you have used the calculator to get a fitted price, you can use this figure as a starting point when comparing quotes from local tradespeople.

The next step is to get quotes from plasterers near you. This allows you to compare firm prices against your estimate and get the job booked in with confidence.