You can’t beat the satisfaction of a DIY job done well. But sometimes the results don’t go to plan – seemingly through no fault of your own – which leaves you feeling far from content. We reveal the most common paint problems that occur and how to avoid them, or how to fix them should they have already occurred.
From paint peeling, blistering and foaming we ask the experts at Dulux to help solve the most common DIY and decorating dilemmas when it comes to paint ideas around the home. Follow the simple steps to avoid your own painting headache.
14 Paint problems – how to fix them
1. Blistering and flaking
The last thing you want in your freshly painted room is for the paint to start blistering and flaking off the wall – and yet it’s a common problem. It can be caused by a number of factors, from moisture trapped beneath the surface of the paint or by paint being applied over a powdery surface. Unclean surfaces can be another cause, highlighting the importance to sugar soap the walls to remove any dirt, oil, and grease.
Excessive movement imposing stress on the paint film can result in cracking which in turn lets in moisture, ultimately resulting in a flaking paint. ‘Resins present in knots causing light coloured paints to discolour or even flake. Resin bleed and flaking is a common problem where dark colours are used on south facing elevation. This is because dark colours absorb more heat than light colours’ explain the experts at Dulux.
To fix it the expert team advise, ‘All loose material will have to be removed back to a firm edge, spot primed with the appropriate primer, and then recoated with the appropriate product. If large areas are involved it’s best to totally strip the surface back to a bare surface and start again.’
This unsightly finish is usually caused by contamination of the underlying surface by soluble stains. It’s easily fixed with good prep. ‘It is important to seal the original stain’ explain the experts at Dulux. ‘You can do that by applying a coat of Polycell Stain Stop prior to re-decorating.’ See how to paint a wall like a professional with our expert guide.
3. Shrivelling paint surfaces
Wrinkling of new paintwork occurs when the surface of the paint dries too quickly. The surface will form a thin skin before the paint underneath has fully dried, meaning it shrinks. This is likely to be worse if a thick coat of paint is applied, especially to horizontal surfaces. It can also occur if a second coat is applied before the first one is completely dry.
‘Allow the paint to dry and harden. This may take several days, or weeks, depending on the drying conditions. When dry, rub the surface down using ‘wet and dry’ abrasive paper, and clean with warm water with a little detergent added. Rinse the surface with clean water and allow to dry before repainting. If you are unable to wait for it to dry it would be best to scrape off the tacky paint taking it back to a sound, dry surface.
The term cissing is used to explain the notion of when paint fails to adhere to a surface. This is caused by painting over contaminated surfaces such as wax, oil or polish. The paint cannot stick to the surface and draws away leaving unpainted patches.
To fix the patchiness the experts advise, ‘Allow the surface to dry and then rub down using ‘wet and dry’ abrasive paper and a solution of warm water and detergent. Once rinsed and dried, repaint the area.’
5. Filler showing through the paint
So often there are holes to be filled before painting, but what happens when the fillers shows through? ‘Make sure that all filled areas are rubbed down smooth and level’ say the experts. ‘You will need to prime the filler before painting to prevent subsequent coats being absorbed more rapidly than in other areas. Use a coat of regular emulsion thinned 10-20% with clean water – once that’s dry, apply a full coat of emulsion.’
6. Foaming paint
Using the wrong type of roller can result in a foaming paint film. ‘Avoid sponge or foam rollers if you’re using a water-based paint. If you’re using a long pile roller, make sure it’s wetted out properly. Foaming happens when air gets into the wet paint film to create air bubbles. When these bubbles burst craters are left on the film surface – sometimes these craters dry to give an even film.’
What to do if the craters still show? ‘You will need to rub down using ‘wet and dry’ abrasive paper using water with a little detergent added. The surface should then be rinsed and allowed to dry before repainting. If this is impractical due to the size of the area, line the affected area horizontally using lining paper and then repaint.’ Before you go in with a roller be sure you know how to cut in paint for perfect edges and corners.
7. Mud cracking
When the paint application is too thick and heavy on textured or embossed surface such as blown vinyl wallpapers or pebbledash it creates a mud cracking effect. This is especially true if the paint was applied by brush. ‘Cracking can also occur when Matt paint is applied over Silk if the sheen is not removed from the silk coating.’
‘One or two thinned coats of paints may fill in the cracks. For internal walls, use a soft sheen paint. If the affected area is over wallpaper, the best thing to do is to remove the paper and start again.’
8. Chalky finish on exterior walls
A powdery finish is most likely caused by a wearing away of the paint by weathering. It could also be evidence of salts seeping from the surface. Fix it like a pro,’Brush the affected area down with a stiff bristle brush to remove as much powdery material as possible before applying a coat of primer, such as Weathershield Exterior Stabilising Primer’ is the expert advice.
‘If the powder is due to salts/efflorescence then wipe the surface with a dry cloth to exhaust the salts before coating with an Alkali Resisting primer to eliminate staining. Then just repaint in your chosen finish.’
9. Cracking plaster
Most commonly an occurrence in new houses, often the result of plaster drying out or movement of the building. To fix it, the team say, ‘Cut out all cracks and remove all dust and debris. Fill the cracks using an appropriate filler. (the Polycell Polyfilla range has a filler for every size of gap). Then just paint in your chosen finish.’
10. Mould growth on surfaces
You can’t paint over mould in the hope that it will disappear unfortunately. Instead you need to treat the problem before painting. ‘Treat affected areas should be treated with fungicidal wash, such as Weathershield Multi-Surface Fungicidal Wash. Once rinsed, allow to dry and coated with your chosen masonry paint, we recommend Weathershield All Weather Protection Smooth Masonry Paint.
11. Loss of sheen
When a gloss loses its sheen, normally only noticed with high gloss paint and varnishes, it’s caused by the settling of dew or condensation on the paint shortly after application – a problem most likely to occur in areas of high condensation like bathrooms.
‘When the surface is thoroughly dry, rub the affected surface down using ‘wet and dry’ abrasive paper and recoat. Only do this if the conditions improve or when the condensation problem is resolved.’
12. Yellowing on and around radiators
The effect of heat can have an adverse reaction on conventional solvent based gloss paints, hence why you will see brilliant white paint on and around radiators sporting a yellow tinge over time. ‘There are two options to prevent this from happening. Firstly, paint the radiator the same colour as the wall as yellowing is much more noticeable with white paint. Alternatively use Hammerite Quick Drying Radiator Enamel (White or Magnolia) or Radiator Enamel (White).’
13. Rain spotting
Surface blemishes occur on a paint finish if rain that has fallen on the surface before the film has had a chance to fully dry. To fix it, simply wait for it the dry, ‘When the surface is thoroughly dry, rub the affected surface down using ‘wet and dry’ abrasive paper. Then recoat.’
14. Rotten wood
Due to its nature wood is prone to rot when exposed to excessive moisture for prolonged periods of time – but wood is a staple material in many homes, so how do we fix the problem? Look to our shed paint ideas for inspiration.
‘Cut out all rotten wood and replace with sound timber’ Dulux advise. ‘Prepare the area before painting – there is a wide range of Cuprinol and Polycell products available to prepare the area ready for painting. Smaller rotten areas of joinery may be strengthened with Cuprinol Ultra Tough Wood Hardener and then filled with Cuprinol Ultra Tough Hardener prior to painting.’