Are you confused between skim coat plastering and undercoat paint? Although both function as primers for finishing coats, they’re not entirely the same. We’ll share with you how they differ in the course of a painting job.
What is Skim Coat Plaster?
Skim coat plastering simply means applying a thin but smooth layer of cement plaster on usually raw substrates or walls that have been stripped off paint, such as rough or uneven walls. Walls that were previously treated with rockstones are to be skim coated to smoothen out the surface before any new coats of paint can be applied.
The purpose of Skim Coating
Skim coating walls or ceilings is to prepare a leveled and repaired surface for subsequent first and top paint coats to apply and adhere well to, so that the paint job can last longer.
To skim coat plaster concrete surfaces requires special techniques by skilled plastering workers. Tools such as trowels and hawks are used to apply the plaster and carry out the plastering job more efficiently.
Undercoat Paint – When do you require it?
Undercoats are necessary for a few circumstances. Undercoat paint is softer and more flexible in application consistency, hence they are formulated to conceal minor cracks (usually hairlines), fill up small pits and peeling patches or marks that are left behind by old hardened paint blobs that have been scraped off.
All these surface imperfections affect the quality of the subsequent paint job, hence undercoats help in priming these surfaces to create an adhesive film for the longer lasting quality of the new paint finishes.
Primer undercoat is also needed when it comes to painting a lighter paint color over a surface of an existing darker paint. The layer of undercoat paint is integral in binding the old and new paint layers together (improve inter-coating adhesion), as well as to ensure sufficient coverage of the lighter pigment in delivering higher opacity of the finishing coat.