Remember that beautiful, blinding white colour your home used to be when it had just been painted? Yet for some mysterious reason your home has now taken on shades of light yellow or orange… in the painting world, this is what we call ‘yellowing’. Typically you may find areas sheltered from sunlight to be more likely to exhibit yellowing, such as areas behind furniture, behind wall mounted objects and within closets. So what causes yellowing? Oxidation is the primary cause of yellowing, as it is a natural process that occurs in alkyd or oil-based paint either due to heat or the absence of light. Darker areas will slowly show signs of yellowing, as light is important in slowing down oxidation. Heat from household appliances such as stoves, heaters and radiators are also agents which can potentially hasten the oxidation and yellowing of your walls. You should never use products containing ammonia to clean surfaces covered with oil-based paint. The ammonia is an agent which can quicken oxidation and cause irreversible yellowing.
Complete prevention of oxidation in solvent-based paints is almost impossible, as it is a naturally occurring process dependent on the environment and conditions exposed to. Yellowing caused by absences of light can be fixed by re-exposing it to light over a consistent and prolonged basis. Unfortunately, yellowing caused by ammonia cannot be reversed, however you can paint over it using an acrylic paint, which does not yellow. Ensure that the surface is cleaned and prepared thoroughly (visit our blog on preparation for more info) before applying the topcoat(s) of acrylic paint.
Having a textured wall can be nice, when it has been done intentionally. Paint blisters (also known as bubbles) are not anything like a textured wall, as these are caused by the paint itself lifting from the underlying surface. This occurs when the paint has lost its adhesion the surface due to heat, moisture or poor preparation prior to paint application. Painting wet, damp areas prone to heavy moisture exposure is often a cause for paint blisters. Also, excessive heat to a surface can also induce paint bubbles as the heat causes the adhesive bonds to weaken, raising it from its surface. Applying oil-based or alkyd paint over latex paint is a definite no no, as the combination of these paints do not result in strong, durable adhesion.
Fortunately, fixing paint blisters is not a very large job to do, as you do not need to strip down the entire wall and redo the paint. Rather, scrape and sand blistering areas thoroughly, patch as required using a suitable filler, and then apply a good primer. Finally use a good acrylic paint to recoat and provide the finish.To prevent blistering from occuring in the future, ensure that when you are first applying paint that you prepare the surface correctly. This includes scraping, sanding and priming, which are all important steps to maximise the adhesion of the topcoat to the surface. Also, avoid painting in overly humid or extremely hot conditions (see product data sheet for manufacturers recommendations), as these conditions can impact the application of paint onto the surface and cause blistering to arise later down the road. For humid areas such as bathrooms, installing vents or exhaust fans are a great idea, as this will remove most of the moisture from the air and help your paint last longer.
Peeling could be considered the final stage of your paints life, as it has now given up and completely removed itself from the surface. There are many reasons behind peeling, so we’ve gone ahead and named the most common causes. As highlighted earlier, we cannot stress enough the importance of correct preparation prior to the application of paint. This fundamental step can and will determine the durability, longevity and overall quality of your paint job. If this is not done, peeling is quite inevitable, thus dedicating enough time to do this correctly can prevent it from occurring. Other causes include: high temperatures and/or intense sunlight, high humidity, applying too many layers of paint, applying new paint over old paint or using paint products that are incompatible to the specific surface.
To fix peeling paint, you will need to scrape of all peeling areas with a scraper and then sand it down thoroughly to create a smooth surface. After wiiping down the surface, apply a primer undercoat and leave it to dry. Then apply your top coat, ensuring that you use the right paint and do not over-do the number of layers.
Ever look up at your ceiling to see dark black, green, brown spots all over? That is mould. Mould is a fungus that proliferates in damp, dark areas of high moisture such as bathrooms, laundry rooms or kitchens. As mould can be quite detrimental to one’s health, such as sinus problems, asthma, pneumonia, rashes, skin irritation and headaches, it is important that you treat the area immediately when you discover it.
To remove the mould, an appropriate sodium hypochlorite solution. After removing the mould, it is important to prevent it from returning, otherwise cleaning it could become a routine. Agents such as mould blocker or anti-bac can be found included in some paint mixtures. Applying this over your now ‘clean’ surface may help prevent the return of mould. However, for issues such as water leakage, high moisture build up, poor light and ventilation, simply painting surfaces with these issues with a paint containing mould blocker, may delay recurrence of mould, but will not solve the problem as the cause of the mould problem has not been addressed. Instead, treat the underlying issue first before treating the mould and painting a fresh layer of paint.
Paint is comprised of many colour pigments held together by paint resin. When paint dries, the paint resin forms a clear layer on the outer surface, holding the colour pigments in place. When paints are exposed to outdoor environments, such as intense sunlight and UV exposure, the thin resin layers eventually becomes worn and can no longer hold the pigments. These dried pigments form chalk-like powders on the surface, which we refer to as chalking.
Fixing chalked surfaces often requires an extremely thorough wash and scrub to remove all traces of chalking and contaminants. Using a water based 100% acrylic latex topcoat to repaint the surface will provide durable and long lasting protection against external conditions. If the chalking is extreme, applying a solvent based primer or sealer binder may be required prior to painting the weatherproof acrylic topcoat.