Before painting your walls, you must take into account their condition: check the quality of the old paint, cover any holes and prepare the surface so that the result is a success. Many of the problems with interior painting are due to a number of common problems. And when your time, supplies, and budget are at stake, then nothing beats getting it right from the start. That is why we offer you a list of common problems and their solutions so that everything is resolved well.


Poor adhesion of paint

When paint cracks or peels off an interior surface, it is usually due to either an over-polished underside or a dirty or polluted surface with sanding dust.

Solution:

  • Remove any paint that does not adhere.
  • Lightly sand surface to remove lustre.
  • Clean any contamination from the surface.
  • Cover the surface with a quality primer.

Water stains

The presence of water on the substrate behind the paint film means there is a proble.. Certain materials, such as roofing tiles, contain water-soluble extracts that seep through paint and create dark brown stains.

Solution

  • Identify the source of the moisture (it could be a leak in the ceiling) and repair it.
  • Apply stain-blocking primer to prevent the water stain from forming. 
  • Paint the surface with acrylic latex paint.

Mold

Mould thrives in warm, humid areas, like the bathroom. It is usually green or grey and looks like dirt. The problem is that mould cannot be removed or killed with soap and water. Even mildew-resistant paint coats cannot remove it as they are designed to prevent it from showing up on the paint surface. The mould must be removed before painting; otherwise, it will continue to grow.

Solution:

  • Scrub the surface with a commercial mould remover or a solution made up of one part liquid chlorine bleach and three parts water.
  • Rinse with plenty of water and avoid contact with skin or eyes.
  • Select a coat with a mildew-resistant finish.

Desiccation cracks

Desiccation cracks resemble hair-thin lines on the painted surface, similar to cracks in the mud of a dried-up river bed. The problem can occur when overly loaded coats are applied, or when painting at low air or surface temperatures.

The solution to be used depends on the severity of the cracks:

  • If it is only a surface appearance problem, you should cover the area with a primer.
  • If the surface has any texture or begins to peel, scrape the surface with a putty knife or sand the cracked surface to achieve a smooth surface.
  • Always be sure to apply a coat of primer before painting.

Poor paint coverage

There may be inadequate paint coverage if the paint is of poor quality, the applicators are cheap, or the paint is spread too much. 

Solution:

  • Use premium quality paint with large amounts of covering pigments.
  • Use quality brushes and rollers.
  • Follow label directions for coverage and adapt based on surface porosity, a porous surface will absorb paint less evenly.
  • If a drastic colour change is made, using a specialized high-coverage primer will benefit the result.

Blistering of paint 

Paint blisters are small to medium-sized bubbles that appear under the paint layer; they are most common in wood panelling and trims.

Possible causes:

  • Painting in full sun on a hot surface causes the solvent vapour to be trapped, as the paint dries too quickly.
  • Painting on damp wood causes trapped moisture to remain and expand in the paint layer.
  • Dew, rain or a high percentage of humidity after the latex paint has dried, in case the paint is of poor quality or the surface to be painted has not been properly prepared.
  • Moisture from the house passes through the walls due to general poor ventilation.

Possible repairs:

  • Scrape off the blistered paint and sand the wood.
  • Let the wood dry completely.
  • Sand, seal and paint on a bright, dry day, but not in full sun.
  • Use high-quality latex paint.
  • If there is poor ventilation in your home, make the necessary repairs to correct that error and allow the walls, roof, eaves, bathrooms, and more to have adequate ventilation.
  • Check if the caulk around windows and doors is loose or missing and make the necessary repair.
  • Consider installing ventilation for the siding.

Paint is flaking due to outside humidity.

Paint peels off due to external moisture penetrating under the paint. When moisture is the cause, it is easy to recognize because the peeling paint films are large and expose the wood. Unlike what happens when there is poor adhesion (the paint peels off as in the form of stains) when the cause is humidity, the detached areas are larger and, often, are located around windows, doors and gutters.

Possible causes:

  • Faulty drains or lack of ventilation causing ice buildup or water backing into the painted area.
  • Paint on a surface damp from condensation or rain.

Possible repairs:

  • Make sure the gutters and downspouts drain the water outside the house.
  • Eliminate the causes or sources of moisture by installing exhaust fans, trim vents, siding vents, louvres, fans, and dehumidifiers.
  • Scrape off the old paint and sand the affected areas.
  • Leave the affected area uncovered.
  • If necessary, apply an appropriate sealer for this.
  • Repaint with the highest quality household acrylic latex paint.

It is necessary to identify these common problems and attend to them with immediate effect to avoid painting failure and save time, energy and financial cost of repairing the damage.