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Why Plaster, Steel or Wood Primer is Absolutely Essential

When painting walls, wood, or steel for the first time, using a suitable primer is the difference between a job well done and a job you will need to do again.





One of my sons recently moved into a newly built townhouse. It was completed and ready to move in late last year and all the tenants immediately moved in. Last week, my son contacted the agents for the property to obtain permission to mount a mirror in the bathroom, of which there was none installed. Seems a bit silly not to put a mirror in a bathroom but it is what it is. Permission agreed but only if they used double-sided tape, the mirror was mounted above the sink. The next morning when he woke to the sound of a smashing noise to find the mirror broken in pieces on top of the sink and the wall missing 4 chunks of paint, leaving a bare plaster wall.


The problem was instantly recognised - no plaster primer had been applied to the wall before painting. Anyone who does decorating or painting on the regular knows that you cannot apply paint onto plaster and that's why they invented plaster primer. The same goes for when painting wood or steel. These surfaces need to be primed beforehand so that the paint coats have something to bond with. Primers are formulated with extra bonding that serves its purpose between surface and paint.









Applying paint directly onto plaster is asking for a failed painting job. It might not happen immediately, but you can be guaranteed that over time the paint will lift off the wall.





Take a closer look at the above image and you will be able to clearly see that the paint isn't even sticking to the plaster wall. It won't take much effort to scrape off the paint and eventually the paint will blister or peel, especially in a kitchen or bathroom or any room with high humidity.







There are plenty of other reasons why a painted finish will fail, but not applying primer is usually the main suspect. Here are a few more reasons why a painted finish will fail:


  • Sub-standard paint quality or paint too watery.

  • Not applying primer according to manufacturer's guidelines.

  • Not allowing primer to dry before painting.

  • Applying paint over too many existing layers of paint.

  • Excess humidity or moisture in the surface (walls or wood).


For paint to adhere to a surface it must be prepped and primed, clean, and dry if you want to prevent later problems. Failure to properly prepare before painting will only mean that you will need to make good and repeat the process, costing you more time and money. Do the job well the first time.





Whatever your favourite paint brand, they are sure to have a Plaster Primer as part of the range, and you will find everything you need to prime and paint walls at your nearest Builders store.. Take note of the manufacturer's guidelines for correct application when applying any type of primer to a surface. DO NOT apply primer over damp plaster but be sure to allow plenty of time for plaster to cure before priming.





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