Priming of the exterior walls using mixture of sand and cement Knauf Vorspritzer
The external wall priming works are carried out with the German PFT-G5 equipment. “Knauf Vorspritzer” is ready for use dry mixture of cement and sand.
Benefits and advantages
- Used on all suitable surfaces at external premises.
- This primer ensures good durable adhesion with KZ Knauf lime plaster.
- Remarkable work speed because the Knauf mixture is sprayed using the PFT-G5 plastering machine.
- Use of primer outdoors, where it is subject to moisture, cold and heat ensures durability of the main plaster KZ Knauf.
- Application of this primer on external walls leads to a uniform absorption of the surface.
- After priming the external walls with “Knauf Vorspritzer” mixture the primed walls crack less.
- Any mineral plaster can be applied on “Knauf Vorspritzer” primer.
Before priming the external walls it is necessary to ensure that the basis is dry, able to bear the load, not frozen, without scurfs or weathered spots, not water repellent.
Sufficiently moistened surfaces are sprayed with pre-plaster “Knauf Vorspritzer”.
“Knauf Vorspritzer” is a factory prepared dry mixture of cement and sand, which consists of grains of 0 to 4 mm thick.
Considering the construction material of the wall it is necessary to wait for the primer to dry.
Things necessary to know when priming the external walls without “Knauf Vorspritzer” mixture;
1. Using no primer when plastering results in very uneven absorption, therefore the plastered surface will not have good quality.
2. Plastering the external walls with lime-cement plaster without primer, water is absorbed into the wall too rapidly, therefore it starts cracking.
1. Grain size 0-4 mm.
2. Compressive strength CS IV
3. Adhesion strength >0,20 N/mm²
4. Visible cracking B
5. Water absorption W0