Tile On Concrete Slab With Cracks

A single thick concrete slab is often used as the foundation for large buildings called slab on grade foundation resting on compacted subsoil and ensuring the building stays level read this post to know how to fix cracks in slab foundation.

Tile on concrete slab with cracks.

Our page top photo illustrates ceramic tiles set on concrete in an antique floor we observed in buenos aires argentina. At left is another ceramic tile on concrete installation in the same city with some interesting repairs. For small narrow cracks that do not show signs of moisture use concrete filler which can be purchased in a tube in vinyl epoxy or latex to fill the crack. If you watch them tile a commercial center or office building which are always concrete floors you never see them use crack prevention.

Cracks in a concrete slab are a problem that i run into frequently. Concrete slabs are essential to the structural stability and design of modern buildings. However cracks wider than 1 8 inch will eventually transfer to the tile it notes. If you install tile over the crack then most likely the crack will eventually.

Applying tile in these situations is really quite simple. See tile isolation membranes. If the slab has cracks or control joints a crack isolation membrane should be used. Cracks in concrete are a sign of a structural problem.

They can be controlled but not eliminated. The tcna handbook for ceramic glass and stone tile installation recommends that control joints in concrete carry through the tile. A crack in a slab of 1 8 inch or less is typically a normal shrinkage crack and not a cause for concern. Generally hairline cracks in the concrete will not present an issue to the tile floor above.

This is known as reflective cracking and it can be easily prevented by adding a crack isolation membrane during installation. Concrete is similar enough to tile in terms of expansion and it doesn t flex so you don t need crack protection just use a decent polymer modified mortar. If tile were set on the slab when it settled the tile would be sheared along the crack sort of like having a mini san andreas fault under your floor. Cracks are nothing out of the ordinary.

In some cases i ve seen cracks that are almost 1 4 in. How can cracking be prevented. Hairline cracks in a concrete slab are rarely a cause for concern. Cracks mean movement and a tile floor isn t meant to move.

Tom meehan a tile installer and owner of cape cod tileworks in harwich massachusetts replies.