Terracotta Tiles: An Old Material That Keeps Earning Its Place

Terracotta is made by shaping refined clay, drying it, then firing it at around 1000°C — a process that gives it that characteristic yellow-to-red color from the iron content in the clay. A piece that has fired cleanly and is free of cracks will ring faintly when struck lightly, a simple way to check quality before it ever goes down as flooring.

It is also one of the oldest building materials in continuous use. Terracotta was the only ceramic produced across both Western and pre-Columbian cultures until higher-fired stoneware appeared in Europe in the 14th century, and it has served as sculpture, pottery, brick, and roofing ever since. The earliest clay pieces were simply sun-dried; later they were hardened in open hearths, and eventually in kilns much like the ones used today. Centuries of continuous use have not dated it — terracotta flooring remains as practical and as handsome a choice now as it ever was.

Laying it correctly

Terracotta tiles need an 8-10mm gap between them, whether set in mortar — which means soaking the tiles for at least half a day beforehand — or in adhesive. Outdoors, especially in harsher climates, expansion joints should sit no more than 2-3 meters apart, and where a floor is boxed in by walls or kerbs, a perimeter expansion joint is usually needed as well. Drainage matters just as much as the joints: an exterior terracotta floor needs a gradient of roughly 1.5-2% so water runs off rather than pooling, since standing water risks both infiltration and, in freezing conditions, damage to the tile itself.

Grouting and sealing

Joints wider than 15mm should be grouted with a sand-and-cement mix; narrower joints do better with a formulated grout product. It pays to work in small sections, so the grout doesn't harden on the surface before it is cleaned off — press it well into the joints, smooth with a trowel, then wipe the surface clean with a damp sponge. A suitable sealer follows, chosen for the tile's porosity, and it will darken the surface slightly on application. Sealing isn't a one-time job: plan on resealing roughly once a year. The upside is that terracotta genuinely improves with age and wear, which is a large part of why it has stayed in use for so long.