Preparing solid wood mouldings for painting

When installing any new wood mouldings or trim, any home renovator  should take time to prepare the wood for finishing before painting. To get professional quality results, this involves several steps of preparation before the final finish of paint is applied. Here is a brief outline of the steps that are required:

STEP 1 – Cleaning

Vacuum the trim thoroughly to remove dust or use a soft, dry cloth like flannel to wipe the surface. Do not use a damp cloth as this will raise the grain of the wood.

STEP 2 – Priming

Select a premium quality primer/sealer to seal the wood. Avoid using drywall primer to save money as it is not formulated to be used on wood and will not give good results. Do not thin the primer as you apply it to the wood. Use a high quality brush and provide an even coat, brushing lengthwise with the grain. The technique you should use is to brush the paint backwards into the wet paint not forward.  Ask your Decor Sales Representative for more information on our pre-primed lineup of trim products that will allow you to skip this step, install the wood moulding immediately and go straight to sanding, caulking, and top coat.

STEP 3 – Sanding

Wait until the primer has completely dried. Then use a spackling compound to fill any holes or minor imperfections in the wood trim. Do not use a hard sanding block. Use a sanding sponge with a medium grit. Use light pressure, always sanding lengthwise in the direction of the wood grain. Avoid sanding at any angle across the grain and be careful not to sand completely through the primer coat. If you do, you should apply a light coat of primer to the area again later and sand it  smooth when the patch has fully dried. Make sure you use a disposable dust mask.

Once you are done, run your hand across the surface of the piece of trim to make certain it feels uniformly smooth. Remove sanding dust by using a vacuum over all the surfaces. Use a dry tack cloth to ensure no dust remains on the surfaces before it is painted. Avoid using a wet or damp cloth.

STEP 4 – Calking

Wood trim can be finished on the workbench before it is installed or after it is installed. If you plan to finish the wood trim after, you should install it and use painters caulking to fill any visible gaps between the trim and the wall. Trim very rarely installs perfectly flush against a wall, and there may be gaps you will need to fill in. Avoid using excess caulking or beading it onto the surface of the wood. Wipe off excess caulking with a dry cloth to ensure the surfaces are smooth. Make certain you allow sufficient time for the caulking to dry thoroughly and set completely before you apply the top coat of paint.

STEP 5 – Top Coat

Many people ask us which is better paint for wood trim, oil base paint or latex. Oil based paints have a more durable finish but they require more skill and experience to apply. Cleanup is harder than with latex and you must use special solvents to thin the paint. Furthermore, many people do not like the strong smell of oil based paints. Latex paint is easy to apply, requires only basic painting skills and is easy to clean up. However, the finish is less durable than oil based paints. If you have not worked with oil-based paints, then you should use latex.

To get good results, make certain you use a good quality paint and good quality brush. Using lower quality products may result in visible brush marks on the final finish. When deciding on what type of sheen for the paint you should use, remember that high gloss paint makes imperfections easier to see. Finishes that are semi-gloss, velvet or egg shell do a much better job at hiding imperfections in the final finish of the trim.

When  you are thinning oil paint, make certain you only thin the first coat with kerosene by only 5% (or 50ml per liter) This technique will not thin the colour of the paint and it will make it easier to spread it evenly across the trim surfaces. Thinning the oil based pain helps it to level out and spread evenly across the trim surfaces. It also provides you with extra “wet time” so that the paint does not dry so quickly. Make certain you apply the paint with the brush along the grain of the wood and use the professional technique of painting backwards into wet areas, not forward. Avoid applying thick coats of paint and over-brushing to prevent brush marks appearing in the final finish when it has dried.

For latex-based paints, use it straight out of the can without adding any thinner. However, make absolutely sure that you mix the paint in the can thoroughly before you start to apply it. Latex that is too thick or too thin will not dry with an even, smooth finish. Ensure that you use a brush designed for latex paint, not one made for oil-based paints. Use even brush strokes following the grain of the wood. As with oil based paints, use the professional technique of painting backwards into wet paint areas, avoid over brushing to prevent brush marks.

STEP 7 – Finish Coat

The finish coat will hide any minor brush marks or imperfections or areas where the top coat of paint was thinly applied top the wood trim. This coat of paint is the one you want to look really good. Before you apply the final coat of paint, vacuum dusty surfaces clean or wipe them down with a soft, dry cloth. Thin oil-based paints for the final coat with kerosene by only 2.5% (25ml per liter). For latex paints do not use any thinner but make certain you mix the can of paint thoroughly to the right consistency before you start. Then use the same brushing techniques described previously used by professional painters to get make your new wood trim look like it was installed by an expert.