How to Repair Damaged Concrete
There are many materials that can be used for surfacing paths, patios and drives, and in time most will need some form of repair or maintenance. The technique required depends on the material. Keeping paths, patios and drives in good condition is not simply a matter of appearance. If the surfaces are allowed to deteriorate, they can become dangerous to walk on, especially when wet.
Concrete is a popular choice for paving because it is relatively cheap and easy to lay. Nevertheless, it can crack, develop holes and crumble at exposed edges.
Before carrying out any repairs to concrete paving, it is a good idea to clean it thoroughly, and the best way of doing this is to use a pressure washer, which directs a high-velocity jet of water at the surface, removing all algae, slime, dirt and debris. Chip out any damaged areas until you have a solid surface to work on.
Minor holes and cracks can be repaired with exterior filler, quick-setting cement or mortar made with fine sharp sand rather than soft builder’s sand. However, you should chip out holes to a depth of about 20mm and enlarge cracks to allow the repair compound to grip properly. Any repairs involving edges will require the use of timber shuttering to contain the repair compound while it dries. Fitting shuttering is fairly simple, using stout timber boards. Solid timber pegs are driven into the ground so that the boards fit tightly against the edge of the existing concrete.
Spread the repair compound over the damaged area – some PVA adhesive (white glue) brushed over the surface will help it stick – and smooth it out with a trowel.
Before the repair compound sets completely, roughen the surface with a stiff brush, as smooth concrete surfaces are dangerous when wet. Finally, remove the shuttering and smooth off any rough areas with the trowel and a piece of sacking.
Apart from brushing, there are several ways you can make a concrete surface more attractive and less slippery. Embedding small stones in the surface is one method, or you could provide surface texture with a float or by rolling a heavy pipe over the concrete.
- Clean the damaged path with a pressure washer to remove all dirt and algal growth.
- Fit a piece of shittering to the edge of the path and drive the pegs home to hold it.
- Mix up the concrete repair compound in a bucket with a small amount of water.
- Use a plasterer’s trowel to apply the concrete right yp to the existing edges.
- Remove the shuttering once the repair compound has dried.