If you are thinking of re-purposing your garage into a living space, workshop or dry storage area, for example, you will probably need to dry out and damp-proof the walls using membranes and tanking. Below is a brief overview of how to approach damp-proofing your garage.
Garage damp-proofing: the basics
Your existing concrete slab floor can be used with the addition of a damp-proof membrane to stop water penetrating into space above. This can be applied in either a solid or a liquid form. Thermal insulation can then be laid down.
Garage walls will need to be brought up to the required standard, and any doors and windows will need to be checked to ensure that they are watertight and in an adequate state of repair.
Whether you are looking for window replacement advice in Dartford, Dunstable garage door installation advice, or any other advice at this stage, there are many specialist companies that will be able to assist you, such as http://garagedoorsrus.co.uk/garage-door-installation-dunstable/.
Garages are not built to the same building regulations as the rest of the house, as they are intended for cars rather than people. There are many resources available online to check the possible planning permission implications for your project, such as https://www.planningportal.co.uk/info/200130/common_projects/25/garage_conversion.
Waterproofing the walls
The existing walls of your garage will often only be a single skin of brickwork. This may need to be upgraded for insulation purposes, which will also greatly improve the damp-proofing. If the wall is abutted to an exterior house wall it will usually be very damp. A cavity tray can be retrofitted into the wall to keep the inside of the wall dry.
Once you have made sure that water cannot run down the interior walls, they will need to be plastered or dry-lined. It can take weeks for the brickwork to completely dry out, so a special membrane can be applied that allows you to proceed with the conversion more quickly.
A mesh membrane is fitted to the garage walls with fixings or dry-walled on to provide a surface suitable for finishing. You will then be able to plaster your damp-treated garage wall using either air gap membranes, sand and cement, or a stud partition wall. The technique that you choose will depend on the individual project, as well as your available budget.