Revealed: Common Mosaic Mistakes

This article outlines seven common mosaic mistakes and how to resolve them. Problems like no colour variation in the grout, inconsistencies in the size of tiles and grouting porous materials are addressed.

1. No Colour Variation

Using tiles and grout that are too similar in colour can unite the piece and result in the design getting lost.

To avoid this, add a contrasting tile colour that will help lift the design and consider using a contrasting grout colour. The colour of your grout should contrast the colours of the tiles so that the design is featured. The individual tiles will be lost if the colour of the grout blends with the tiles. The mosaic will look more like a picture than a mosaic.

2. Burying Objects in Grout

So you've added some dimensional objects to your mosaic, but they are buried under grout; how do you fix it? Wait for the grout to dry but not cure (about an hour or so), and dig it out of the excess grout using a repositioning tool or something similar. An old toothbrush comes in handy for cleaning off any hard-to-reach grout. Use some saved grout to make touches-ups as necessary.

3. Inconsistencies in the Size of your Tesserae

Inconsistencies in the size of the tesserae used can upset the flow of the mosaic and cause the eye to focus on the imbalance. Here are two common inconsistencies:

a) Placing smaller-sized tesserae on the edge of the mosaic will draw the eye to the sides of the mosaic.

b) Placing a smaller-sized piece of tesserae amongst larger-sized pieces. Repeating the inconsistency throughout the design will balance it.

4. Grouting porous materials

Grout will absorb into porous surfaces, like unglazed ceramic tiles. If you have used a porous material in your mosaic, seal it or cover it up before grouting. Masking tape or blue tack can effectively cover up exposed areas before grouting.

5. Grout lines that are larger than expected

So your grout line is a little larger than you planned; what do you do? Leave it or fill the space with small pieces of tile. Avoid the latter and leave it as it is. Placing smaller irregular pieces in the design will draw attention to the inconsistency, whereas the wider grout line will disappear within the mosaic.

6. Tesserae falling off as the mosaic is grouted

To fix this problem, remove any excess grout with a cotton wool tip, then re-stick the tile with adhesive and carefully grout.

7. Adding water to your grout after it has begun to set.

Doing this may cause the mixture to weaken, which will cause the grout to crack.