Wall Surface Preparation

Exteriors Interiors Stains Wall Surface Preparation

The golden rule of DIY - preparation - applies to outside work too. It'll pay off in the long run because results will look better and last longer.

Stripping paint back

Test your paintwork in several areas by cutting a small cross with a knife and pressing adhesive tape across the cut. Then, rip the tape away. If paint comes with it, the paintwork needs to be stripped back to a firm base. For heavily layered areas, use a heat gun or a chemical stripper. Paintwork that is in good condition just needs a thorough washing then a fine sanding. Spot prime any bare timber.

Blistering, flaking and peeling

Blistering shows up where dark colours have been applied over many layers of old paint or where moisture is trapped below. Eliminate the source of moisture, then strip back using a heat gun or chemical stripper. Seal cracks around windows and doors with a suitable filler.

Bare masonry, bricks and concrete

Allow new concrete surfaces to cure for a minimum of 28 days. Wipe salty or lime build-up away. Check all surfaces and remove loose material with a wire brush. If the surface is powdery, porous or highly glazed you will need to apply a primer recommended for the material - ask at your Guthrie Bowron store.

Window frames

Scrape any areas of loose paint and feather the edges with a medium grade sandpaper. Use a suitable filler to fill any cracks or flaws. Spot prime, sand then wash the whole window frame down to remove the last dirt and grime.

Galvanised iron roofs, bare metal and spouting

Check your roof for soundness, and strip back old flaking layers of paint. Brush with a wire brush and spot prime any problem areas. Bare metal surfaces must be rust free and clean. Treat with a rust remover and wash down with clean water. Wash all metal or plastic spouting also.

Nail head stains

Replace old steel nails with galvanised nails. Sand or wire brush any stains off the paint then countersink the new nails to 3-4mm below the surface. Spot prime with a rust guard product and then fill and sand.

Timber preparation

Any bare timber which has been exposed to the weather for more than a month needs to be sanded back before painting. Rotten or decayed timber must be replaced. Where movement is possible - around doors and windows, apply an exterior flexible filler.