Applying Microcement on Walls: guide for vertical surfaces
Applying microcement to walls is the simplest project for getting started with this coating: the material goes straight over the plasterboard, plaster, cement or tiles you already have, in a 2-3 mm layer, and the wall ends up seamless, joint-free and in the colour you choose. There is no need to chip anything off or remove rubble, and with ready-to-use microcement nothing needs mixing or pigmenting: you open the container and apply it.
Updated September 2026.
This guide covers the whole process: which walls it can be applied to, the five steps with the real drying times for each product, why the wall is the easiest surface to work with, how to use the roller and what changes in a bathroom or over tiles. The steps are those of the wall microcement kit, designed for dry interior walls over plasterboard, plaster, cement or tiles; for bathroom and kitchen walls, use the kit for that room.
Where you can apply microcement to walls: recommended rooms and spaces
The wall is the surface most often coated with microcement on walls, ahead of floors and countertops: it covers quickly, does not take footfall or knocks, and suits any room in the house.
- Living rooms: a whole wall, or just the one behind the sofa or television. The seamless, matt finish adds depth without overloading the space, and works with wood, metal and textiles.
- Entryways: it is the first wall you see on entering and is usually small: a 4 m² kit covers it entirely, in a weekend.
- Home offices and workspaces: coating just the desk wall marks out a work area within a living room or bedroom without building a partition.
- Hallways and bedrooms: long walls with no splashing, the easiest of all. In a narrow hallway, a light, continuous colour makes it look wider.
- Bathrooms: bathroom walls are coated the same way, but with the microcement kit for bathroom, which reinforces the varnish with Smart Booster for steam and water. You will find real projects in these ideas for microcement walls in the bathroom.
- Kitchens: the splashback between the countertop and the wall units takes grease and splashes, so it goes with the microcement kit for kitchen, also with Smart Booster. The rest of the kitchen walls, away from the work area, are done with the wall kit.
- Commercial premises: a seamless surface, with no joints for dirt to collect in, and cleaned with a damp cloth. For high-traffic areas, the varnish is reinforced with Smart Booster.
How to apply microcement to walls in 5 steps
The system is four products, always in this order: primer, Smart Base (the preparation coat), Smart Liso (the finish) and Smart Varnish (the sealer). The microcement kit for walls includes all of them, together with the grit 40, 220 and 400 sanding discs and the instructions; the tools (trowel, roller and tray) are sold separately, in the Smart Tools kit. No previous experience is needed; what is needed is respecting the drying times between coats. The application takes three days, and the varnish reaches full cure at seven days.
One condition applies to the whole process: keep the room between 20 and 22 °C if possible, and never point a heater at the wall to speed up drying.
1. Preparing the wall to be coated
The wall must be clean, dry, sound and free of dust, grease, flaking paint or damp. Cracks and chips are filled with filler and left to dry before continuing; microcement is a low-thickness coating, and it does not hide defects, it copies them.
If the wall is tiled with tiles, mosaic tiles, terrazzo or porcelain, the joints are filled and levelled first with Smart Jointer, using a spatula or trowel, and left to dry for 12 to 24 hours. Without this step, the pattern of the joints would end up showing through the finish.
2. Priming: the key step for microcement adhesion
The primer is the bridge between the wall and the microcement, and which one to use depends on whether the substrate is absorbent or not. On plasterboard, plaster, cement or concrete, apply Smart Primer ABS, the primer for absorbent surfaces; on tiles and other non-absorbent substrates, Smart Primer PLUS, the maximum-adhesion primer. Both are applied by roller, in a uniform coat, and after 30 minutes you can carry on. The kit includes whichever one matches the substrate you choose.
The fibreglass mesh that some applicators fit after the primer is not part of the Smartcret system: on walls it is not needed.
3. Smart Base, two coats
This is the preparation coat, the one that gives the coating body and that the finish keys onto. Stir the container and apply it in a thin coat, less than 1 mm per coat: with the roller to spread it and the polycarbonate trowel to smooth it, as explained below. Leave it to dry for 4 to 8 hours and sand it with the grit 40 sanding disc. Then repeat for the second coat.
4. Smart Liso, two coats
This is the finish, the finest-grain microcement in the system. A very thin coat, less than 0.5 mm per coat, applied with the trowel in arcing movements; 4 to 8 hours of drying and sanding with the grit 220 sanding disc. The second coat is what gives the final appearance, and the whole build-up comes to around 2-3 mm thick. Sanding each coat once it is dry is what achieves the smooth, seamless surface.
5. Sealing and protection with the varnish
The microcement sealer Smart Varnish is what protects the coating against water, stains and cleaning products, and what gives it the matt finish. It is applied 24 hours after the last coat of Smart Liso: three coats by roller, 4 to 6 hours apart, sanding the first two with the grit 400 sanding disc. All three coats are needed, none can be skipped. On bathroom walls and the kitchen splashback, the varnish is mixed with Smart Booster, which is included in those kits; on the rest of the walls, Smart Varnish is used on its own.
The day after the last coat of varnish, the wall can be touched and decorated; maximum resistance is reached at 7 days.
Why is it easier to apply microcement to walls than to other surfaces?
Introductory courses for professional applicators start with the wall, and for the same reasons it is the recommended surface for a first project at home.
The grain is finer. On a floor the finish is done with Smart Medio, a medium-grain product, because it has to withstand footfall, chairs and knocks. On a wall the finish is Smart Liso, the finest-grain microcement in the system, applied in coats of less than half a millimetre and leaving a smoother, more seamless surface that is softer to the touch. On a floor, strength comes first; on a wall, you can make the most of the material's aesthetic side.
There is no waiting time before use. A newly coated floor cannot be walked on until the varnish has dried, and furniture waits even longer. A wall carries no load: apply the last coat of varnish and, the next day, decorate.
It needs less cleaning. A wall, except for the kitchen splashback, does not take spills. Day to day, a damp cloth with neutral soap is enough; for a coffee or marker-pen stain, use Smart Cleaner, the cleaner formulated for the varnish itself. What should never be used is bleach, ammonia, vinegar or abrasive products, as they attack the varnish.
How to apply microcement to walls with the roller technique
Ready-to-use microcement comes prepared and pigmented in the container: it is not mixed with resin, water or pigment. It is formulated to be applied with a roller, and that is the difference that makes it accessible to anyone who has never worked with a trowel.
The technique has three concrete advantages over traditional trowel application:
- It is faster: the roller covers the wall almost like paint, in much less time than spreading the material with a trowel.
- It deposits just the right amount: with a trowel it is easy to load more material than needed; the roller, dipped and drained, spreads a thin, uniform coat, which is what the system calls for.
- It requires no special skill: dip, drain and roll. The trowel is used afterwards, only to smooth what the roller has left.
The step-by-step process with the kit's products is as follows:
- Clean the wall and, if it has joints, fill them with Smart Jointer and wait 12 to 24 hours.
- Apply the primer by roller: Smart Primer ABS on plaster, plasterboard, cement or concrete; Smart Primer PLUS on tiles, mosaic tiles, floor tiles, ceramic or porcelain. Wait thirty minutes.
- Apply Smart Base and Smart Liso with the roller and smooth with the trowel. Both coats of Smart Base and both of Smart Liso are spread with the polyamide roller and then smoothed with the polycarbonate trowel, tilted at about 45° and worked in arcs in every direction. The roller is passed first vertically, then horizontally. Between four and eight hours of drying and sanding between coats, with the disc that corresponds to each product.
- Finish with Smart Varnish, three coats by roller with 4-6 hours between them. If the wall is in the bathroom or on the kitchen splashback, the varnish takes Smart Booster; in the living room, bedroom or hallway, Smart Varnish on its own.
The detail of every step, with quantities and timings, is in the interactive application guide that comes with the kit.
What to keep in mind before applying microcement to a wall
The question that decides the kit and the varnish is which room the wall is in. A bedroom, living room or hallway are dry walls; a bathroom or a kitchen splashback take steam, water and grease every day. The process is the same, but two things change: the protection of the varnish and, if there are tiles, the preparation of the substrate.
How to apply microcement to bathroom walls
Every hot shower fills the bathroom with steam, and that steam ends up on the walls. That is why bathroom walls are not done with the wall kit but with the microcement kit for bathroom: the same products and the same steps, with the varnish reinforced with Smart Booster, which is what gives the resistance to water, soap and cleaning products that a shower wall needs. The microcement itself is the same; what changes is the layer that protects it.
The most common mistakes when plastering bathroom walls are covered here, along with the fix for each one.
How to apply microcement to tiled walls
If the wall is tiled, the microcement goes straight over the tiles, with no need to remove them. The wall, bathroom and kitchen kits each have a version for this substrate, with Smart Jointer and Smart Primer PLUS. Before starting, it is worth checking four things:
Joints: they are filled and levelled with Smart Jointer so they do not show through the microcement, which is a coating only 2-3 mm thick.
Tiles in good condition: none loose, cracked or hollow-sounding. A tile that moves would take the microcement with it and end up cracking; fix or replace it before starting.
Painted tiles: if the paint is sound, prime straight over it with Smart Primer PLUS; if it is flaking, it must be stripped or sanded first, because the microcement would key onto the paint rather than the tile.
Textured tiles and border tiles: microcement is a low-thickness coating and copies whatever is underneath, so a pronounced texture or the pattern of a border tile would end up showing through the finish. Loading on more product to hide them increases the risk of cracking. In these cases, the recommendation is to level the texture first or replace the border tile.
The full process over tiling, with video, is in the guide to microcement over tiles.
Professional tips and techniques so you get it right when applying microcement to walls
- Practise first on a small surface, such as the entryway wall or the inside of a cupboard, to get the feel of the roller and the trowel.
- Protect with masking tape the skirting boards, frames, corners and sockets, and mark out the work area.
- Respect the drying times: 30 minutes for the primer, 4-8 hours between coats of microcement, 24 hours before the varnish and 4-6 hours between coats of varnish. This is the most common mistake, and the one that shows most in the result.
- Roller vertically then horizontally, and the polycarbonate trowel at about 45°, in arcs and in every direction, to avoid leaving marks.
- Sand each coat with the disc that corresponds to it (40 for Smart Base, 220 for Smart Liso, 400 for the first two coats of varnish) and remove the dust before the next one.
- Define the corners with the spatula so the joins between walls come out clean.
- Temperature and ventilation: between 20 and 22 °C if possible, with no draughts and no heaters pointed at the wall.
The kit to get started
The microcement kit for walls comes in 4, 8, 16 and 24 m², for plasterboard, plaster or cement or for tiles, with the matching primer, Smart Base, Smart Liso, Smart Varnish, the sanding discs and the instructions. You choose the colour, the size and the substrate, and the price is fixed: the material comes to £26–43 per m². In the UK, a professional applicator charges around £120–200 per m², labour included.
If you want to know how microcement is applied to any type of surface, see the step-by-step general guide.
