Drywall primer for wallpaper - why is it needed

Gusevsky Andrey Anatolyevich

Primer for drywall wallpaper - an obligatory technological stage of decoration

It may seem to a person who is not directly connected with the finishing work that such a perfectly even and smooth material as drywall after installation does not need additional processing for finishing. This is not true.
Putty and primer for drywall under wallpaper - a mandatory procedure on which the quality of the coating depends.

Why do I need a primer

Often, even the finishers themselves neglect the priming of the gypsum plasterboard surface before painting or wallpapering, limiting it to processing seams and self-tapping screws at best. But this only speaks of dishonesty or insufficient experience of such workers.
A competent master, answering the question whether it is necessary to prime drywall before wallpapering, will answer only in the affirmative.
Explain why:

• After installation drywall sheets on its surface there are holes with hats of screws inside.
  They, as well as the joints between the sheets, must be repaired with putty to level the surface. The primer will improve the adhesion of the putty mixture with paper, prevent its peeling;

Stitching

• The cardboard with which GKL sheets are coated absorbs moisture well. If you glue wallpaper directly on it, the glue consumption will increase.
  In addition, it will absorb and dry very quickly, making it difficult to adjust the wallpaper to each other;
• Wallpaper glued directly to drywall without first priming, while trying to remove them during the next repair, the top layer of paper will also be pulled along, violating the integrity of the surface. As a result, you will either have to repair it or change the wall covering.

It is very difficult to remove wallpaper from non-primed walls

In a word, there can be a lot of problems when ignoring this stage of finishing, and they will turn out to be much more expensive than the price of the primer and the time spent on its application.

Rules for processing drywall primer

So, it is necessary to prime drywall. When, how and with what composition do you do this if you are going to do all the work yourself?

Primer selection

It is not difficult to choose a primer - its composition and scope are always indicated on the package. In our case, it can be a special composition for work on GCR, and a universal deep penetration primer suitable for different surfaces.
Nevertheless, it is worth paying attention to some points that will help to make the right choice:

• Brand and manufacturer. You should not buy "what is cheaper", there is a risk to buy a fake or a product that includes toxic substances. It is better to pay more, but be sure of the quality and safety of the product;
• Application area. The primer for outdoor work in its properties can fully meet the requirements for moisture and heat resistance, penetration and other characteristics.
  But it often contains harmful substances, therefore it should not be used in interior rooms;
• Drying speed. This parameter is important if you need to finish the repair in a short time, since the primer for gluing wallpaper on drywall (seeDrywall decoration for wallpaper: do it right) usually applied in two layers with a break for complete drying of each;
• Colour. Most often, the composition is transparent or white, but some manufacturers add color pigment to it to improve the quality of the coating.When applying it, you will see well the untreated places;

For reference. Do not be afraid that the colored soil will shine through light wallpaper. After drying, it becomes colorless.

• The presence of additives. Often on the packaging you can find an indication of the type of primer - frost-resistant, fireproof, antiseptic.
  For example, if you are doing repairs in a room with high humidity, it is advisable to treat the walls before attaching wallpaper to them with a composition with antiseptic properties that prevent the development of fungus and mold.

Antifungal Primer

How to apply

It is hardly worth describing in detail the process of applying a primer to the surface - this work is simple, the main thing is not to leave unstained places and let each layer dry well. If you wish, you can watch a video that talks about preparing plasterboard walls for decoration.

But it is worth focusing on the fact that GKL needs to be primed three times:

• Before sealing joints, the joints between the sheets, corners and attachment points are processed;
• Before leveling the surface, the entire area is primed to increase the bond strength of the putty with cardboard;

The photo shows the moment of GKL priming after grouting

• Before stickering the wallpaper, at least two primer layers are already applied on the putty walls to strengthen the surface and reduce its absorbency. Thanks to this primer layer, later on you can easily dismantle the old wallpaper without damaging the drywall paper layer.

Note. Before applying the primer, putty walls must be sanded with sandpaper to level and smooth.

It is most convenient to apply the composition with a roller on a long handle, having previously processed with a brush hard-to-reach places - corners, niches, joints of walls with a ceiling, etc. It is advisable to cover the floors before this, since it is unlikely to manage without splashes and drips.

Conclusion

We hope that this instruction convinced you of the need to use a drywall primer and brought some clarity to the question of its selection and application. Despite the fact that this work does not give any visible changes, its benefits are obvious, and neglect of this step may affect the quality of the finish.