Outdoor tiles: grip, thickness and wall cladding

What makes a tile an outdoor tile

An outdoor tile has to cope with rain, standing water, sand and sun, and with people who walk on it in wet shoes or barefoot. Marazzi, an Italian tile maker, tells buyers on its outdoor tile page to start from how the space is used: exposure, how often people walk there, whether water stays on it, and how large the area is. A covered balcony and a pool edge need different tiles, even if they look alike in a showroom.

Both makers quoted here build their outdoor ranges on porcelain stoneware. Daltile’s exterior range page also lists quarry tile: an unglazed tile of clay and shale fired at high temperature, which it offers for patios and walkways.

Grip for outdoor floor tiles

A wet outside tile floor is where slip classes matter most. The Villeroy & Boch slip-resistance sheet reprints the German workplace rules ASR A1.5, which name the class for each kind of area.

Grip for outdoor floor tiles

Outdoor area	Class in ASR A1.5 or DGUV rules
Entrance, outdoors	R11, or R10 with displacement space V4
Stairs, outdoors	R11, or R10 with V4
Sales area, outdoors	R11, or R10 with V4
Pool surround, walked barefoot	B (ramp angle over 18°, up to 24°)

V4 means a profiled face with at least 4 cm³ of open space under the walking level per dm², so water and dirt have somewhere to go. These are rules for workplaces. The same sheet notes that no rules exist for private homes, so for a private terrace the table is a yardstick rather than an obligation. Outdoor floor tiles without an R class on the box give you nothing to compare.

Thickness and laying: 8.5–10 mm or 20 mm

On the Marazzi page, standard outdoor collections are listed at 8.5 to 10 mm thick and are laid with adhesive, which the maker describes as the method for stable, permanent surfaces. Marazzi also makes 20 mm porcelain and recommends it for driveways, pool edges and paths under heavy use.

The thick tiles can be laid in ways thin ones cannot. Marazzi lists dry laying of its 20 mm range on gravel, grass and sand, and on raised floors. A raised floor on pedestals makes sense, in its words, where slopes, access to the space below or pipes under the floor are needed. For cars, it names 20 mm tiles fixed with adhesive.

Size changes the look. Marazzi suggests large formats for wide terraces, where fewer joints show, and medium or small ones for balconies, paths, steps and areas with many cuts.

Outdoor wall tiles and elevation tiles

Outdoor wall tiles, also sold as exterior wall tiles or elevation tiles, carry no foot traffic, so slip class does not apply to them. Marazzi offers porcelain stoneware for exterior walls and thin porcelain slabs for ventilated façades, where the slabs are fixed on an anchoring system in front of the wall; it says the anchoring system must be chosen with designers for each building.

For outdoor wall tiles design, Marazzi uses the same stone, concrete and wood effects on walls as on its outdoor floors, so a terrace floor and the wall behind it can match.

Terraces and balconies: what goes under the tile

On a balcony or a terrace above a room, the waterproofing goes under the tile adhesive, not over the finished tiles. The data sheet of K11 Polymer Cement Waterproof Coating, which Kitovu has in stock in Zanzibar, names balconies and pools among its uses and states that tiles can be laid on the cured coating. It gives about 1.5 kg/m² for each millimetre of film, applied in 2 to 3 coats.

For glazed tiles on a terrace, the Villeroy & Boch wear sheet asks for wear group 4.

Is the 1200 × 600 R10 tile for outside?

The Beige Porcelain Tile 1200 × 600 mm, Matt Anti-Slip R10 has a granular matt surface and slip class R10. By the table above, R10 alone is one class short for an outdoor entrance unless the tile also has a V4 profile, and the label does not give a V value. Outdoor use is not confirmed for this item; for covered verandas and indoor floors, see floor tiles.