Preparation ignored during renovations can compromise the finish, increase costs, and bring forward new repairs, even when the chosen paint is of quality, while a product applied before painting is gaining ground among professionals for addressing failures that start at the base of the wall.
Applied before the finish paint, the preparatory base can reinforce fragile surfaces, improve adhesion, and reduce failures related to crumbling, peeling, and inadequate preparation, as long as the cause of the problem is identified before the start of the service.
In many renovations, the color choice happens before evaluating the base, although dust, weak plaster, old paint without adhesion, and moisture can compromise the result shortly after, increasing the risk of rework and new expenses.
When the preparatory base is indicated
According to Coral, the water-based preparatory base was developed for new walls, peeled surfaces, saponified areas, or places previously painted with lime, and can be used in internal and external environments before applying the finish.
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Painters are now betting on a little-known solution that promises to increase the durability of the paint and prevent up to 3 problems that make renovations more expensive without many people realizing the real reason beforehand.
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Engineers manufacture still-wet wood and, by controlling how each layer shrinks during drying, make the pieces curve on their own to form a 22-meter spiral tower with walls only 13 centimeters thick.
By forming a preparatory layer, the product improves paint adhesion, creates a barrier against the alkalinity of the masonry, and helps preserve the paint for longer, provided it is used under the conditions indicated by the manufacturer.
In practice, these functions can reduce three recurring sources of rework: particles that detach from the plaster, finish with low fixation, and peeling caused by a wall that did not receive enough preparation before painting.
Hand test helps evaluate the plaster
Before choosing the product, however, it is necessary to evaluate the resistance of the plaster, as a surface that crumbles to the touch or allows a small hole to be opened with a finger may be too fragile to receive just a preparatory layer.
When the degradation is intense, the guidance from Suvinil is to redo the plaster, wait for the curing period, and only then prepare the wall, preventing the paint from being applied over a layer incapable of supporting the finish.
For the redone plaster, the manufacturer states 28 days of curing before preparation and painting, a timeframe that needs to be included in the construction schedule to prevent haste from compromising the base again and causing premature failures.
In less severe situations, where the plaster releases few particles, the primer can help fix the loose material and leave the surface in better condition to receive the subsequent stages of the painting system.
Wall cleaning influences adhesion
Besides the plaster’s resistance, cleaning directly affects performance because dust, dirt, oil, and parts of old paint without adhesion can prevent proper material fixation and promote peeling or crumbling in the future.
Cracks, irregular texture, and poorly executed plaster also require prior correction, as the result depends on the firmness of the underlying layer, and the primer alone does not replace the repair of a seriously damaged base.
Moisture requires correction before painting
Another decisive point is moisture, as bubbles, peeling, and crumbling may be related to leaks, infiltrations, or excess water, conditions that need to be diagnosed and resolved before resuming any painting service.
In cases where the origin is in the pipes, Suvinil recommends seeking a professional, as the hydraulic repair must occur before preparation, and only after eliminating the water entry can the wall receive the appropriate treatment.
This sequence prevents the primer from being mistaken for a waterproofing agent, since its main function, in the situations described by the manufacturers, is to consolidate certain surfaces and favor the adhesion of the paint applied later on the wall.
Appropriate tools improve application
As for the tools, Coral states that its water-based primer can be applied with a soft-bristle brush or a low-pile wool roller, following the instructions available for the chosen product.
According to the company, a 18-liter container can cover up to 275 square meters per coat, although the coverage varies according to the surface conditions, a difference that needs to be considered in calculating the necessary amount.
Since there is no single proportion for all products available on the market, dilution must strictly follow the packaging instructions, avoiding mixtures based solely on habit or previous experiences with different formulations.
Correct preparation reduces the risk of rework
More than adding a step to the renovation, proper preparation involves diagnosis, defect correction, cleaning, proper application, and respecting curing times, factors that work together to increase the durability of the finish.
When this sequence is ignored, the cost may reappear in the form of scraping, redoing the plaster, purchasing new materials, and hiring labor, especially if the cause of the problem remains active under the paint.
Although there is no reliable survey to support the claim that “2 to 3 painters” recommend the product, the two manufacturers consulted provide technical indications for specific wall preparation situations before painting.
Before just choosing the color and starting the service, do you usually check if the plaster releases dust, if there is old paint without adhesion, and if any visible bubbles might be directly linked to the presence of moisture?
