Karatsu-Roku by Estudio

Collection Summary

Karatsu-Roku by Estudio is a porcelain wall tile collection from Spanish manufacturer Estudio Cerámico. It combines two finger-tile series in a shared 11.5 x 23 cm (4.5″ x 9″) format, 8.5 mm thick. Karatsu is the glossy series, offered in six colors. Roku is the matte series, offered in seven colors with a silky finish. The design draws on elongated “kit-kat” or finger tiles, so each piece reads as a set of narrow vertical strips once grouted. Because both series share one format and thickness, designers can work across gloss and matte, and across a broad color range, within a single layout.

Design & Aesthetic

Karatsu-Roku is defined by fine vertical rhythm: the finger-tile pattern brings a tight, repeating line to any wall.

• Karatsu (glossy): Polar White, Chalky, Wear, Midnight, Charcoal Grey, and Rusty Red. Estudio Cerámico describes the palette as deep and inspired by elements of nature.
• Roku (matte): White, Beige, Greige, Grey, Green, Blue, and Red. Estudio Cerámico ties Roku to Japanese aesthetics and botanicals such as sakura blossoms, green tea, rice fields, and bamboo forests.

Both series carry V3 (moderate) shade variation, so walls will show tonal movement from piece to piece rather than flat color. Grout color has an outsized effect on a finger-tile surface. Estudio Cerámico notes that grout changes the product’s final appearance and recommends a test area before grouting the full wall.

Material & Craftsmanship

Estudio Cerámico classifies both series as porcelain on its technical data sheets. The two finishes are not technically identical:

• Roku (matte) tests in water absorption class BIa (< 0.5%).
• Karatsu (glossy) tests in class BIb (0.5% < E ≤ 3%) and has a lower modulus of rupture.

The collection is made in Spain.

Design Applications

Tile X Design lists Karatsu-Roku for wall applications in bathrooms, shower walls, kitchen backsplashes, and residential interiors. Estudio Cerámico also positions Karatsu for kitchens, bathrooms, and commercial projects.

• Backsplashes: The vertical strip pattern adds fine-scale texture behind a range or along a counter run without introducing a busy pattern.
• Shower and bath walls: Matte Roku suits calm, botanical palettes. Glossy Karatsu adds reflectivity in smaller rooms.
• Hospitality and retail feature walls: The shared format allows a glossy accent band or panel set within a matte field.

Specifying Karatsu-Roku

• Choose the finish with its specification in mind. Gloss vs. matte affects more than appearance: Karatsu and Roku have different absorption classes and breaking-strength values (see Product Specifications).
• Avoid wide offsets. Estudio Cerámico’s installation instructions advise against offsets greater than 25%, to prevent lippage between adjacent pieces. A stacked or minimally offset layout follows that guidance; a standard half-offset running bond does not.
• Plan for variation. With V3 variation, blend tiles from multiple boxes during installation. The manufacturer recommends ordering at least 5% extra and requesting the same shade for any reorder.
• Grout selection: The manufacturer recommends CG2 or RG grout, waterproof grout in areas with water contact, and epoxy grout where water contact is frequent.
• Adhesive: The manufacturer specifies C2 cementitious adhesive or R epoxy adhesive.

Product Specifications

Karatsu (Glossy), per Estudio Cerámico technical data sheet:

• Format: 11.5 x 23 cm / 4.5″ x 9″
• Thickness: 8.5 mm
• Water Absorption: 0.5% < E ≤ 3% (BIb)
• Modulus of Rupture: > 30 N/mm²
• Thermal Shock Resistance: Complies
• Crazing Resistance: Complies
• Frost Resistance: Complies
• Chemical Resistance: GA (household chemicals), GLA (low-concentration acids)
• Stain Resistance: 5 (max)
• Shade Variation: V3 (moderate)

Roku (Matte), per Estudio Cerámico technical data sheet:

• Format: 11.5 x 23 cm / 4.5″ x 9″
• Thickness: 8.5 mm
• Water Absorption: < 0.5% (BIa)
• Modulus of Rupture: > 35 N/mm²
• Thermal Shock Resistance: Complies
• Crazing Resistance: Complies
• Frost Resistance: Complies
• Chemical Resistance: GA (household chemicals), GLA (low-concentration acids)
• Stain Resistance: 5 (max)
• Slip Resistance: Pendulum Class 2 (UNE 41901 EX); > 36 PTV (TRL and 4S rubber); DCOF > 0.42 (ANSI A326.3); R10 (DIN 51130); B (DIN 51097)
• Shade Variation: V3 (moderate)

Frequently Asked Questions

Can Karatsu and Roku tiles be combined on the same wall?

Yes. Estudio Cerámico produces both series in the same 11.5 x 23 cm (4.5″ x 9″) format and 8.5 mm thickness, so glossy and matte pieces can share a layout. A mockup is the best way to judge how the two sheens read together.

How should grout color be chosen for a finger-tile look?

Grout defines the individual strips, so it controls how graphic or how quiet the wall appears. Estudio Cerámico recommends testing the grout in a small area first, because grout color changes the finished look of the tile.

Can Karatsu-Roku be installed in a brick or running-bond pattern?

Estudio Cerámico advises against offsets greater than 25% to avoid lippage. A stacked layout or a 25%-or-less offset follows the manufacturer’s guidance; a traditional half-offset does not.

Roku has slip-resistance ratings. Can it be used on floors?

Tile X Design lists Karatsu-Roku for wall applications only. Confirm any floor use with your TXD representative and Estudio Cerámico’s technical team before specifying it.

Is Karatsu-Roku suitable for shower walls?

For water-contact areas, Estudio Cerámico recommends waterproof grout, and epoxy grout where water contact is frequent.