Rules for applying liquid wallpaper to paint: how to properly prepare a painted wall

Although it may seem simple to apply liquid wallpaper over a painted wall, careful preparation is necessary to guarantee a smooth and durable finish.

It’s important to realize that the texture and condition of painted walls can vary greatly before you begin. Certain paints may have a glossy or slick finish, which will hinder the liquid wallpaper’s ability to stick properly. Others may require maintenance due to flaws or old paint layers.

We’ll walk you through all the necessary steps in this guide to get your painted wall ready for liquid wallpaper. By adhering to these guidelines, you can attain a polished appearance, starting from evaluating the wall’s surface and finishing with the appropriate primers and treatments.

What is liquid wallpaper

Liquid wallpaper, also known as silk plaster, is actually a kind of decorative plaster with a unique component composition. The strength, level of evenness, and presence of defects of the surface determine whether or not they can be applied to surfaces like water-based layers or other paint types.

While they may have many different parts, the primary ones are:

• fillers made of fibers (silk, cotton, cellulose), as well as dried algae, etc.;
• binders in which CMC glue is a mandatory component;
• water-based acrylic dye;
• glitter, mica, stone chips, etc. can be added for decorativeness.

Silk plaster is offered for sale in two forms: semi-liquid (in plastic buckets as a container) and dry mixes (in bags as packaging). They need to be made ahead of time: diluted with water, kneaded until smooth, and then given a 12-hour period to swell. Semi-liquid mixtures can be prepared faster by simply adding more water, stirring, and waiting a short while (the cooking time is listed on the package).

Applying the coating very thinly results in a solid, joint-free canvas once it has dried. Certain surfaces feel and appear like fabric.

Is it possible to apply liquid wallpaper to paint without preparation?

Pre-painted walls that are not prepared can’t have these materials applied to them. Since they might have:

• irregularities that will then appear from under the thin finishing layer,
• stubborn greasy stains that interfere with the adhesion of the base and finish,
• the paint or plaster layer may peel off, or there may be other defects.

Should you apply the mixture where the old paint still has residue on it, it won’t adhere well and you’ll need to replace it quickly.

Only minor depressions on the bases, measuring no more than 0.5 cm, are permitted; these decorative materials can be used to level the defects. Larger flaws and unevenness need to be plastered over. Weak spots need to be pre-chipped off and thoroughly cleaned, even of tiny particles.

It is acceptable to use these materials in the same without doing proper preparation. However, only if the prior liquid wallpaper layer was applied in accordance with all technologies will the repair be of excellent quality. The surface only needs to be cleaned and degreased at that point.

Any stains that are already there must be removed; otherwise, the fresh wallpaper will show them.

Additionally, any paint layers need to be leveled and cleaned carefully, or they need to be completely removed. The type of paint determines the cleaning procedure.

It is important to note that liquid wallpaper will never stick well to smooth surfaces or an oily paint layer. Because this material requires a rough, absorbent base for better layer adhesion.

Sand the preliminary paint, then coat the surface with Betonkontakt or another intermediate primer containing small abrasive particles.

Oil

When it comes to oil paint composition:

• processed organic oils (oil oil);
• alkyd synthetic resins;
• organic pigments;
• other fillers.

It takes a lot of time and work to prepare such bases if oil paint was applied earlier. The ingredients in oil paints provide extremely thick coatings that are challenging to remove.

If the wall is smooth, sanding it with sandpaper or a sanding grater will be sufficient. Next, in order to improve the adhesion of the finishing layer to the base, a deep-penetration primer layer must be applied.

Acrylic

These water-soluble substances are created by adding dyes, plasticizers, and other fillers to synthetic resins. After drying, acrylic mixtures produce incredibly strong coatings that cannot be removed with water or solvents. As a result, grinding and other mechanical techniques are needed to remove them.

Water-based

Water-based paint cannot be applied over liquid wallpaper due to the unpredictable adhesion. When these mixtures are made on water, they produce thin coatings. They include:

• adhesives;
• pigments;
• plasticizers;
• other fillers.

Such walls need to be soaked in water, applied with a spray bottle, before being cleaned. Using a spatula or other similar tool, it will be much simpler to scrape the painted layer off the wall once it softens.

Pentaphthalic

This mixture, which is finely dispersed, is also inappropriate for the base for this kind of finishing. It is composed of pigments dissolved in pentaphthalic varnish. The end product is a thin layer of hydrophobic coating. Using tools like sandpaper, a grater, a grinding disc, and others, it is simple to remove mechanically. The wallpaper’s adhesion to the base will be weak if it is not removed.

Nitro enamel

These paints and varnishes are composed primarily of cellulose nitrate; the pigments are dissolved within the varnish. A fast-drying, extremely durable paint layer coats the painted surface. It is removed mechanically from the surface. To make the layer easier to remove, pre-treating it with a solvent or special softening agent is advised. It is sometimes acceptable to prime and pre-treat walls with sandpaper or a grater when they are very tidy, smooth, and have long-lasting nitro enamel coatings.

TIP: It is advised to make tiny notches with a metal tool, no deeper than 0.5 cm, for improved liquid wallpaper adhesion if the mixtures are applied to painted walls that are still excessively smooth after sanding.

The video demonstrates how to paint a wall completely white:

Proper preparation of painted walls for liquid wallpaper

Consists of multiple phases:

• cleaning of peeling coatings;
• leveling using plastering, puttying;
• priming;
• application of the finishing coating.

Important: A layer like this needs to be thoroughly cleaned if the paint was mixed with two or more colors.

If not, every one of these multicolored pieces will be visible through the thin coating of liquid wallpaper that has been applied to the painted lower one. If the old coating is extremely resilient and challenging to clean, sandpaper or a grinding disc will need to be used. Next, use Betonkontakt or a thin layer of gypsum plaster with fine-grained filler. Apply a colored primer layer on top that matches the liquid wallpaper’s shade.

To achieve a smooth and durable finish, careful preparation is necessary before applying liquid wallpaper to a painted wall. The three most important steps are priming the wall to form a solid bond, sanding down any glossy areas, and thoroughly cleaning the wall. You can achieve a flawless application that improves the appearance and longevity of your walls by adhering to these guidelines.

Methods for removing old paint

Because liquid wallpaper cannot be applied over a paint layer, previous coatings must be cleaned. The paint type that was applied to the old layers, the amount of surface wear, the existence of cracks, irregularities, and other flaws, and other factors all influence how the old layers are removed.

1. If there are a lot of flaws on the walls, then they will have to carry out their full alignment – getting rid of exfoliating plaster or paint, applying new plaster, primer, and then it will only be possible to apply liquid wallpaper.
2. When the walls are smooth, smooth, it will be enough to clean them with a grinding machine, apply a primer, and after drying it – liquid wallpaper.

What to do when the paint is not removed

I am in these circumstances where the wall is really challenging. There are many irregularities that cannot be fixed with a grinding machine because the paint is held very firmly in some places.

Note: All paint removal operations need to be done in a room with adequate ventilation and safety precautions.

Next, extra actions are taken:

1. Burning off the paint layer with a blowtorch or you can use a gas torch for this.
2. Mechanical removal is carried out using metal tools – chipping, breaking up problem areas.

A painted wall must be carefully and meticulously prepared before applying liquid wallpaper. You build a solid base for the liquid wallpaper to adhere to by carefully cleaning the surface, fixing any damage, and using an appropriate primer.

It’s crucial to test a small area first, particularly if the paint is old or in bad shape. This step gives you confidence in the finished product and helps ensure that the wallpaper will adhere without any problems.

By following these instructions, you can achieve a smooth and long-lasting finish that will enable the liquid wallpaper to change the appearance of your room with little effort.

Video on the topic

How to apply liquid wallpaper to walls. Application of liquid wallpaper.

Liquid wallpaper on oil paint. Stairs in liquid wallpaper.

what to do with walls painted with oil paint

Primer solves everything! Preparing walls for liquid wallpaper SILK PLASTER #shorts