Match the product to the substrate
A deep-penetrating primer is used on suitable absorbent substrates. Selection depends on the wall and the full installation system. Do not transfer one product’s recommendations to another or dilute a primer without its manufacturer’s instructions.
Remove dust before priming
Clean the dry wall after sanding. Apply the chosen primer with a roller or brush according to its instructions rather than arbitrarily increasing coverage. The instructions and substrate determine whether another coat and an interval between coats are required.
7–12 hours is not a general rule
The previously mentioned 7–12 hours is only a planning guide. For example, KNAUF lists 3 hours for Tiefengrund, while the Ceresit CT 17 technical sheet states up to 2 hours depending on conditions. Your product’s current instructions take priority over this article.
Wait for full drying before hanging
Temperature, humidity and absorption affect the process. Do not schedule installation by the clock alone: confirm surface readiness. Keep the primer name and tell the installer when it was applied and how many coats were used. This is more useful than simply saying the wall is primed.
Check before ordering
- A compatible primer selected
- The substrate cleaned before application
- Drying checked against product instructions
The selected product and conditions determine the drying period, not a universal online number.
Sources and instructions
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