How do you determine the moisture level of a wall or other surface before painting?

It is very important to ensure that the moisture levels of walls or wood surfaces are suitable for paint. Damp is often the cause of discoloured plaster, loose wallpaper, peeling paint and ‘tell tale’ damp patches.  Some damp can be noticed by mould growth or a musty odour. Often damp cannot be seen which, left unchecked, will cause problems. The most accurate way to determine moisture levels is with a damp detector. It will assess acceptable moisture levels and indicate excessive moisture requiring remedial action. Damp testing should be done methodically. Start outside, determining strategic places for damp. Examine the inside for potential problem areas. Important areas to test: floors and joints, door and window frames, skirting boards, walls, chimney breasts, inside cupboards and under the stairs, ceilings, especially under flat roofs, bathrooms, loft space. The detector can locate the source of moisture by taking different readings on the same wall. We can assist you with damp testing.

Can you explain why the colour in the paint can is not the same when it dries out on the walls?

The explanation begins with the fact that the components of paint reflect light differently when they are wet (in-can) compared to when they are dried (on the wall). These subtle differences are quite common and not a reflection on the quality of a paint product. A handy tip to make sure you are happy with the end colour on your wall is to use a sampler pot, apply the paint and check how it looks after drying.

Can I use a water-based paint over areas previously painted with solvent-based paint?

In short, yes you can. However some preparation is required before you start. First the surface needs to be sanded to a dull finish with a fine grit sandpaper, then wiped off with a damp cloth. A top quality pure acrylic water-based paint can then be applied quite successfully.

How should I paint on fresh plaster?

Fresh plaster should be allowed to dry thoroughly over a period of weeks depending on how thick the layer of plaster is and the ventilation in the room. Usually the plaster changes to a pale colour when drying and feels powdery smooth to touch. Once dry apply a quality primer followed by 1-2 layers of a high quality topcoat.

When and why is using a primer important?

Priming is essential when the surface is porous in any way, the surface has never been painted before or when the surface contains substances which can bleed through (eg. dirt, water and tobacco stains, tannins in wood such as mahogany).  Priming has an important role; it blocks out staining materials from the surface being painted, it provides a good base for a uniform topcoat appearance and ensures maximum adhesion to the surface being painted. Primers can be solvent-based or water-based.

What if I just paint over the spores on my wood siding?

That will probably seal them in. It may solve your problem, but will give a pebbly appearance to your paint job. Each repainting will seal in the artillery fungus even more and your fungus problem will re-appear all the time.

Are there any registered fungicides that will kill the fungus? How about a weak solution of household bleach?

Mold and mildew can be a problem in areas that have high humidity and poor ventilation such as bathrooms kitchens, wine cellars, etc.  bleach, would be very temporary, as it leaches out. Thales Wine Cellar Services have tested and approved our Hydrowash Fungicidal as safe for use and pose no risk of organohalogen contamination.

I have a mould problem in my bathroom. What is the easiest way to get rid of it and what should do to prevent it coming back?

The easiest way to get rid of mould is by washing the surface with Hydrowash Fungicidal. It will kill all the mould almost instantly. Preventing it from coming back depends on what type of paint you have on the walls and ceiling at the moment. We would recommend you use Dekro Hygiene Coatings.

How long should I wait before applying another coat of paint?

Although the paint will dry to touch fairly quickly, we recommend waiting four hours between coats. High humidity, low temperature, poor ventilation and thicker films will increase the recommended dry time.