How Are Cracks Repaired Before Exterior Painting?

Before painting, cracks are repaired according to their width: hairline cracks with a filling primer or elastic filler, wide cracks opened up and closed with repair mortar and mesh. Paint is applied to protect the repaired surface, not to hide the crack.

The repair in seven steps

1. The cracks are located and marked.
2. The crack is opened into a V, and loose material and dust are removed.
3. The opened surface is primed.
4. Elastic filler or repair mortar is applied.
5. Reinforcing mesh is embedded over wide cracks and material junctions.
6. The surface is brought level with its surroundings.
7. Once dry, primer and two coats of paint are applied.

Materials by type of crack

• Hairline crack: filling primer or a crack-bridging elastic paint.
• Medium crack: elastic acrylic filler.
• Wide, moving crack: repair mortar and reinforcing mesh.
• Window and sill junctions: a sealant suitable for exteriors.

Why is paint alone not enough?

Paint covers the crack for a few months; as the wall moves, the same line opens again and water gets in.

Will the repair show?

It will if only the repaired area is painted. That is why, after repair, the whole facade is painted, or at least from corner to corner.

In what weather is the repair done?

In dry, mild weather; filler does not bond to a wet crack. Erdağ Yapı lists crack repair as a separate item in its painting quote; details are on our exterior facade paint page.