Once the interior plasterboard walls are installed, your construction project is really starting to take shape, with just the finishing touch needed – painting.
The first step in the job is to make sure that the plasterboard surface is prepared properly to ensure that the paint lasts and is free from as many imperfections as possible. The joints, corners, fixings and cornice installation should be sanded to a smooth, even finish with feathered edges to minimise scuffing to the paper surface of the plasterboard.
The sooner the painting takes place after plasterboard installation, the better. Although it’s important to ensure that the joints are dry before applying the first coat, leaving an untreated plasterboard wall for too long will result in the joints reabsorbing moisture, which can lead to uneven surfaces or cracking.
Once the surface is prepared and dust-free, you’re ready to apply the sealer undercoat. This is an essential step for a top-quality painted finish.
There are generally three accepted ways to apply paint to plasterboard walls, by brush, roller and spray.
For a professional and timely finish, we recommend keeping the brush application to cutting in the edges. Brush painting is more time-consuming that the other two methods and doesn’t provide the textured finish that evens out the substrate and covers minor imperfections.
With time constraints on many building projects in the current climate, it’s fast becoming a standard to spray paint the walls. Whilst this is an accepted industry practice, and obviously provides a quicker solution, an essential element to this method is to back roll every coat while the paint is still wet to create a textured finish that is better able to conceal any small imperfections in the wall, at the same time as providing continuity between the plasterboard and joints.
However, whilst spray painting may be 20% quicker than other methods, the downsides, such as the need for protecting items against over-spray such as cabinets, doors and windows, wet-on-wet back rolling and the highlighting of joints may negate that time saving.
The best results by far are achieved with rolling. By applying a quality sealer undercoat, followed by two top coats in the desired colour with a roller, painting professionals will achieve the best results that enhance the work of all those who have contributed to the project, either directly or indirectly.
This applies to any type of interior room, whether it’s a bedroom, living area, bathroom or kitchen.
For wet area rooms, such as laundries and bathrooms, a semi-gloss to full gloss paint is recommended for extra resistance to wear and tear from cleaning, as well as resistance to mould growth. If these gloss level paints are used, the same painting rules apply, with the additional need for a Level 5 finish on the plasterboard. Similarly, interior designs that are intended to be coated with dark paints to achieve a particular style, need a Level 5 finish. The skim coat of this finish provides an even layer that smooths out any small imperfections in the plasterboard and provides a more even surface between board and joints.
Regardless of your chosen painting method, following the recommendations of both the paint manufacturers and plasterboard suppliers is essential to the end results, and to the warranty applied to both paint and board.
If you need more information or tips on painting your plasterboard walls, contact your local paint supplier or the Master Painters’ Association.
Also read our blog Painting Plasterboard: What are the standards?