STEP 3: Marking angles and planning wall planes

Find out how to correctly mark angles in a room and when keeping 90° is essential. This Michno System guide explains why bathrooms and kitchens need precise geometry and how to use a laser to avoid mistakes with tiles, furniture and built-in units.

After accurately setting the wall plane with a laser, it is time to move on to the next stage — checking and planning the angles between the walls. This is the moment when the installer should consciously decide:

• whether to aim for perfect 90° angles in a given room,

• or whether it is enough for the walls to be visually straight and aesthetically even.

In older buildings, angles are rarely preserved — walls can “run away” by several centimetres. Trying to straighten them completely may cause a significant loss of space on one side of the room. That is why conscious planning and agreeing with the investor where angles are really needed is essential.

Where are angles mandatory?

You do not have to fight for perfect geometry everywhere, but there are rooms where maintaining 90° angles is absolutely necessary.

Bathroom This is one of the places where angles must be set with full precision. Why? Because even a minimal difference in the angle between walls will immediately affect the appearance and functionality of the interior: At the bathtub or shower tray – the angle must be perfect so that the elements fit without gaps and do not require a thick layer of silicone. At the washbasin or bathroom cabinet – if the wall does not hold the angle, unattractive “triangles” appear between the furniture and the wall finish. When laying tiles – an angle deviation of even 2–3 cm means the grout line will not run straight and the corner will look visibly crooked. Practical tip: Use a cross-line laser – set one beam along the main wall and the other perpendicular to it. Make control marks. This helps avoid errors that, after finishing, can no longer be corrected without removing the tiles.

Kitchen The second room where 90° angles are mandatory is the kitchen, especially on the wall with built-in furniture. This is where a missing angle is the most common cause of problems during furniture installation. Kitchen units must fit tightly to the wall – any deviation creates a gap between the furniture and the wall that is difficult to cover. The worktop and upper cabinets must run in one line – even a small deviation will make the edges shift in relation to each other. Corner units for example L-shaped kitchens, require a perfect angle — otherwise the cabinet bodies will not close properly or a gap will remain between worktops. Tip: When measuring and planning a kitchen, always set the angles with a laser from the wall with the main kitchen run. If the walls “run away”, it is better to correct them in this place than to force the furniture to fit later. In a kitchen built up to the ceiling, every millimetre matters.

Where can slight deviations be allowed?

In living rooms, bedrooms and corridors, you do not have to maintain perfect angles at all costs.
It is usually enough for the walls to be in one plane and visually straight.
If, after levelling one wall, another runs out by a few centimetres, it is not always worth correcting — especially if it would mean losing space.

Example:
In a 12 m² room, forced angles can “take away” even 6–8 cm of width — which means about 0.5 m² less usable space.

What should be agreed with the investor before installation?

If you are working for a client, a discussion about angles is mandatory before straightening the walls:

• Show the real wall layout with a laser — the investor will immediately see the differences.

• Explain the consequences of the decision — keeping the angle means losing a few centimetres of space, but gives a better visual and installation result.

• Agree on a compromise — angles are mandatory in the bathroom and kitchen, while slight deviations can be accepted in other rooms.

How to set angles with a laser?

• Set the cross-line laser so that one line runs along the first wall that has already been levelled.

• Use the second line to project a perpendicular line — this is your reference line for the new wall.

• Make marks on both walls — they will help you control the layout when drilling and installing the discs.

• Check the distances between the lines at several heights — this will show how much the wall “runs away”.

Common mistakes when setting angles

❌ No consultation with the investor before starting to straighten the walls.

❌ Forcing all walls straight even where perfect angles are not needed.

❌ No second laser measurement at the corners.

❌ No control marks — once drilling starts, it is difficult to return to the original geometry.

❌ No right angle in the bathroom or kitchen — this causes problems when installing furniture, worktops, tiles and built-in appliances.

Setting angles is a stage that determines the aesthetics, functionality and precision of the entire wall finish. It is worth taking a moment to consciously plan where angles are necessary.