A priming solution for porous substrates and sealing anhydrite screeds prior to the application of tile adhesive. It is also used as an admixture for improving cement-based adhesives.
Supplied as a concentrate.
Not recommended for:
- Priming wet or frozen surfaces.
- Priming impervious surfaces e.g. existing ceramic or vinyl tiles or paint.
- Should not be used in grouts - does not act as a waterproofing system.
- Surfaces to be clean, dry, sound and free from grease, wax, etc.
- Remove all friable residues (peeling paint, old adhesive for vinyl tiles, laitance, etc.).
- For general priming dilute 1 part weber AD250 with 2 parts of clean water.
- For priming/ sealing anhydrite and gypsum plaster, dilute 1 part weber AD250 with 1 part of clean water.
- Apply primer in a regular thickness using a wool roller or flat paint brush, ensuring complete coverage. Leave to dry completely before overcoating (1–4 hours at 20ºC).
- As an admixture where movement is expected: Use weber AD250 un-diluted and mix with the powder as recommended on the bag, but note that the mixing ratio may change slightly.
- As an admixture for bonding onto impervious tiles or substrates: Pre-dilute one part weber AD250 with two parts of clean water and then mix with the powder.
- A performance-enhancing admixture for weberset plus and weberset rapid plus, when tiling onto low-porosity substrates or tiles, wooden floors, green screeds, and heated floors.
- A surface treatment: Priming porous or dusty surfaces prior to tiling/ sealing gypsum based substrates prior to the application of a cementitious product.