Preparing unpainted surfaces

Exterior timber:

All sharp edges should be slightly rounded by planing, scraping or sanding. If timber has been exposed for some time or damaged it must be sanded before painting. All sanding should be carried out with the grain. Wash, or dust off as necessary before painting.Cracks and holes in the timber should be scraped clean of any soft material, and filled with an appropriate filler.

Interior timber:

Sand smooth before painting. Timber should be sanded along the grain to prevent fibres being raised. Remove all dust and dirt before painting.

Paperfaced gypsum board (Plasterboard):

Ensure joints are smooth and surface is dust free. Particleboard, MDF:Dirt and grease should be removed, edges should be filled or fitted with an edge strip and holes filled before sanding. Do not use oil based undercoats on fibre board.

Galvanised Steel and Zincalume:

New metal should be thoroughly degreased by wiping with mineral turpentine. Structural galvanised steel (pipes, beams, hand rails etc) must be thoroughly abraded by sanding or grinding to remove chemical treatments from the surface and ensure adhesion of coatings.

Iron and Steel:

If no rust is present, the surface should be thoroughly degreased by wiping with mineral turpentine. Loose rust can be removed with a wire brush or power tool.


New lead surfaces should be thoroughly washed with water, and allowed to dry. Lead flashing may be painted directly with Bristol WeatherTough.


Remove loose particles by dry brushing the surface down. Fill holes and cracks with a suitable filler. Wash the surface if necessary with a solution of water and household detergent. Rinse with water and allow to dry.


Paint will serve best if concrete is cured and dry when painted. New concrete may be wet under the surface and this moisture may later cause blistering and peeling of coatings. Aging is a reliable surface treatment for concrete. With age, moisture and alkalinity are reduced. Concrete should be allowed to dry for 4 weeks. Fill all unwanted holes with suitable filler. Wash if necessary with a solution of water and household detergent to achieve a clean surface before painting.

Cement render:

Surfaces must be cured and dry prior to painting, at least 6 weeks for oil based paints and 4 weeks for acrylic paints. Treat any mould with a suitable mould wash solution.

Set plaster:

Leave to cure for 28 days prior to painting. Fill cracks with a suitable plaster filler and smooth the filler by lightly sanding.

Initial Preparation

The most important things to do before you start painting

Initial Preparation Find out more

Do's and Don'ts

10 incredibly handy do's and don'ts to help you get started painting

Do's and Don'ts Find out more

Clean up

Cleaning up correctly will mean your paints and brushes both live long and happy lives

Clean up Find out more
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