Grout for Handmade and Zellige Tile: Joints, Types and Sealing

Zellige and other handmade tile are usually grouted with a cement-based grout in a color close to the tile, in joints from nearly tight to about 1/8 inch, using unsanded or a fine-aggregate grout rated for the narrowest joint. Seal unglazed edges and porous bodies before grouting when the tile maker recommends it, and avoid epoxy on heavily pitted glazes.

What makes handmade tile different to grout

Machine-made porcelain is pressed to tight tolerances and often rectified. Handmade tile is formed by hand or in simple molds, dried and fired with natural variation. Moroccan zellige, in particular, is cut from hand-formed terracotta, glazed and fired in traditional kilns, then often hand-chipped to shape. That process produces character, and it also produces conditions grout must cope with:

• Size variation. Tiles in one box can differ noticeably in length and width, so joints taper.
• Thickness variation and warpage. Adjacent tiles sit at slightly different heights. Some lippage is inherent and expected with zellige.
• Chipped and rounded edges. Edges are irregular, with exposed clay where glaze has chipped.
• Glaze texture. Pinholes, pits, crawling, crazing and uneven glaze thickness are typical. Each one is a place for grout and haze to lodge.
• Porous clay body. Low-fired terracotta bodies absorb water readily, which affects both staining risk and how fast the tile pulls water from fresh grout.

Because of this, grouting handmade tile is less about strength and more about appearance and cleanability. The grout must fill joints that change width along their length, must not stain the clay, and must come off a textured glaze without leaving a film.

Choosing joint width for irregular tile

Joint width on handmade tile is a design decision and a practical one. ANSI A108.02 guidance is that joints should be wide enough to accommodate the tile's actual size variation. With handmade tile, that variation is large, and many tile makers publish their own recommendations. The typical ranges:

The "tight joint" zellige look

Zellige is often installed with tiles nearly touching, so the grout line is irregular: wider where edges curve away, almost zero where they meet. This is a deliberate look, but it has consequences. Grout must be able to fill joints from a hairline to perhaps 1/8 inch in the same row. Unsanded grout or a fine-aggregate grout rated down to 1/16 inch handles this. Standard sanded grout cannot pack into the tight sections and leaves voids. A joint that is truly zero still needs a slight gap where the tile meets walls, corners and other materials for movement, which should get sealant.

Even when tiles touch at the face, the edges usually taper away underneath, so there is a V-shaped channel to fill. Pack grout into it firmly; partially filled channels hold water behind a thin skin of grout and crack. Our grout joint width guide covers how to measure variation, and unsanded grout explains its width limits.

Which grout type to use

Cement grouts

Cement-based grouts are the most common choice for zellige and handmade tile because they clean off textured glaze easily with water while still workable. A high-performance cement grout (ANSI A118.7) gives lower absorption and better color consistency than a standard A118.6 grout, which helps in kitchens and baths. For the tightest joints, use an unsanded grout or a high-performance grout whose TDS lists a minimum joint width of 1/16 inch or less. See high-performance cement grout.

Epoxy

Epoxy is extremely stain resistant, but on handmade tile its strength becomes a weakness: cured epoxy residue in glaze pits, crazing and chipped edges is very difficult to remove, and haze on uneven surfaces is hard to see until it has cured. Several zellige suppliers advise against epoxy for this reason. If you need epoxy, such as on a shower floor or a counter, grout a test panel with spare tiles first, and consider pre-sealing the tile with a grout release or sealer the epoxy manufacturer approves.

Premixed and urethane grouts

Single-component premixed grouts are convenient and color consistent, and some work well with handmade tile. Others are sticky and harder to clean from textured surfaces than cement grout. Check the TDS for minimum joint width and for any cautions about textured or porous tile, and test. See premixed grout.

Sanded grout and scratching

Most zellige and handmade glazes are not easily scratched by grout sand, but some soft, low-fired or metallic glazes can be. If the joint is 1/8 inch or wider and you plan to use sanded grout, rub a little on a spare tile with a damp sponge first and check for scratching.

Pre-sealing: preventing stains on clay and glaze

The most common handmade tile grouting disaster is pigment staining. Grout paste is a fine suspension of cement and pigment in water. When it touches porous clay, the clay absorbs water and draws pigment in with it. With zellige, that clay is exposed along every chip and edge, and dark grout leaves a dark outline around every tile that no amount of cleaning removes.

Prevention steps, following the tile maker's instructions where they exist:

• Seal the tile before grouting with a penetrating sealer approved by the tile supplier, after the setting material has cured enough to allow it. Keep sealer out of the joints if the grout manufacturer warns that sealer reduces grout bond, or use a product designed as a pre-grout sealer or grout release.
• Choose a grout color close to the tile or slightly lighter. Light grout on light clay stains least visibly.
• Test on spares: set two or three tiles on a board, seal and grout them exactly as planned, let them cure, and inspect the edges.
• Do not soak the tile to slow grout set unless the tile and grout makers recommend it; wet clay draws pigment faster.

After grouting and curing, many suppliers recommend a final sealer application over both tile and grout in wet areas. See how to seal grout and do you need to seal grout.

Grouting technique for textured, irregular tile

The general process follows standard grouting (see how to grout tile), with a few changes for handmade tile:

• Mix slightly stiffer within the TDS water range. A stiffer mix packs better into tapered joints and stains less.
• Work smaller areas. Porous clay pulls water from grout, so it stiffens faster at the edges.
• Float diagonally and pack firmly, then remove as much excess as possible with the float edge held nearly upright, so less grout needs sponging off the textured glaze.
• Sponge gently with a well-wrung sponge. Uneven tile height means a sponge will dip into low spots and drag grout out of joints next to high tiles. Use light passes and a soft touch at lippage.
• Use a soft brush for pits. A soft nylon brush or a damp microfiber cloth wrapped on a finger lifts grout from glaze pits better than a sponge.
• Remove haze early. Cement haze on textured glaze is much easier to remove in the first hours than after it cures. See how to remove grout haze.

Handmade tile in showers and kitchens

Zellige and handmade ceramic are used in showers and on backsplashes, but they need more care than porcelain. The terracotta body can absorb water through crazing and chips, and grout joints with variable depth are more likely to have thin spots. In wet areas:

• Build a proper waterproofed assembly behind the tile; grout is not waterproofing. See shower grout.
• Use a high-performance cement grout and seal tile and grout as the tile maker recommends.
• Expect natural patina: some zellige darkens slightly in wet areas over time as water reaches the body.
• Use sealant, not grout, at inside corners and changes of plane, per TCNA EJ171.

For grout color choices that flatter irregular tile, see the grout color guide.