Stone Flooring Follies Picture Framing

Stone Flooring Follies and how to avoid them

Picture-framing is a discolouration of the stone around its edge. Normally all four edges are affected and the effect is seen for a few millimetres in from the edge of each tile.

The problem is associated with a number of factors and occurs after grouting.

1. Cheap grouts: These should be avoided. Stick with well known brands such as Bal, Mapei, Ardex and Larsen as their grouts tend to be colour stable.
2. Grouting wet stone: Natural stone tiles must be perfectly dry before grouting. Wet stones encourage the movement of colour from the grout into the edge of the tiles.When the stone does dry out the colour is still visible around the edge of the stone tile.
3. Grouting stone tiles before they have been adequately sealed: This is the most common cause of problems. If unsealed, the stone will pull the grout in at it’s edges and the ‘colour‘ in the grout will stain the stone tile. An impregnating sealer should be applied to all stone tiles before grouting. It is important that the stone tiles are dry in the first place and that the sealer is left overnight to dry.

Some stones are more prone to picture framing than others: Stones that are particularly susceptible are all the dark grey and black basalts, Belgian bluestone, Jura beige and Jura blue/grey Limestones. Moleanos and similar white or cream fine-fossiled Limestones. These stones must, in particular be bone dry and heavily sealed before grouting.