ᐅ Buying non-rectified tiles?

Hello everyone,

I’m currently having trouble making a decision.
I am renovating a single-family house and am currently selecting tiles.

Approximately 125 sqm (1345 sq ft) of floor area will be tiled, as well as two bathrooms. One of these bathrooms has a walk-in (level-access) shower.
The plan was to have uniform flooring throughout the house with 60x60 cm (24x24 inches) tiles.
In the bathroom with the walk-in shower, the shower area will be visually differentiated using the same 60x60 cm (24x24 inches) tiles, and the bathroom walls will be tiled with 30x60 cm (12x24 inches) tiles.

At the tile specialist dealer, I was offered very nice tiles from a Grohn series, and all the tiles would be from the same series.

The quote I received was very reasonable. The tiles are R10B slip-resistant and full-body color (through-body porcelain).

However, as I saw on the Grohn website, these tiles are not rectified or calibrated.

I asked the tile dealer about this, and he said it is not a problem; they would simply use 3 mm (1/8 inch) grout joints instead of 2 mm (1/16 inch) joints that are typical for rectified tiles.

I also plan to cut skirting boards from the base tiles, meaning two pieces from the 30x60 cm (12x24 inches) tiles.

Nevertheless, I am a bit unsure whether I should buy the non-rectified tiles, even though I really like how they look.

What are your opinions on this?

Today, hardly any manufacturer still produces tiles that are not rectified.

Does anyone have experience with non-rectified tiles and grouting, maybe even with the Grohn manufacturer? The series is called Studio.

The rooms are about 16 sqm (172 sq ft), 4x4 m (13x13 ft).

However, the living room is 8 meters (26 ft) wide.

If I am unlucky with the tolerance, I could have irregularities of over 1 cm (about 0.4 inch) at the end of the room in the worst case — for example, about a 1 mm (0.04 inch) size difference per tile.

I also have a second question.

The old terrazzo staircase should be tiled over. The steps have a 2 cm (3/4 inch) overhang. I want to level the area below the overhang to make tiling easier.

What is the best material to use for leveling? I plan to prime the whole area with a dispersion-based bonding agent and then use adhesive and reinforcing mortar, since it bonds well and I still have some bags left. Does anyone have a better suggestion? Regular leveling compound is not suitable because it is a vertical surface. If it cracks, it’s not a big deal since it will be tiled over anyway.

Thank you very much.

Rectified and calibrated mean the same thing.

With natural stone, unrectified looks better in my opinion. Rectified tiles have slightly narrower grout lines, which simply appear more seamless with large formats. For smaller tiles, I wouldn’t find that as much of an issue. However, narrower grout lines also mean that the installer has to work more precisely since uneven grout lines are more noticeable. This takes more time, which in turn costs more money.

Yes, I am aware that modern large-format tiles look best with narrow grout lines. However, the difference between 2 mm (0.08 inches) and 3 mm (0.12 inches) should not be too noticeable. Ideally, it would be helpful to hear from people who have installed 60x60 cm (24x24 inches) tiles with a 3 mm (0.12 inches) grout line.

Here is another picture of the tiles.

Oh, and the tiles should be laid with cross joints. So no staggered pattern, herringbone, or anything similar.