Why to use primer Ceresit  CT 17?


Unbonded dust is separating agent which can dramatically lower adhesion of next layer leading to a crack formation and debonding of material. Dust must be vacuumed and its rest will be successfully bonded to substrate due to the primer performance, making adhesion surface suitable for next steps.


Special primer formulation ensure efficient penetration in depth of the substrate structure and close the capillary pores, thus strengthening surface of the substrate.


Using primers we reduce water uptake from subsequent layer and thanks to that we have following benefi ts: uniform adhesion on any fragment of the substrate; subsequent materials dry in the same conditions; easier application of next layers e.g. adhesive, skim coat etc… reduced risk of too fast drying of subsequent layers thus less cracks or delamination; economic use of subsequent materials e.g. adhesive, plaster, skim coat etc…


Before and after using Ceresit CT17

Strengthens the surface

Binds Dust

Protects next layer
from crack formation or delamination

Reduces absorbency


Look more closely at Ceresit Primer CT17 in action


Example application fields of Ceresit CT17

Under Plasters & Skim coats

Highly absorbent substrates must be primed at least 2 times to prevent micro-cracks.

Under levelling

CT 17 is also recomended for heated floor systems.

Under paints

Ensures homogeneous coverage and color.

Under wallpapers

Dying time 2-4 hours.

Under tilling

Ensures uniform bonding of tile adhesive to the substrate


How to use it?

Shake the primer

Apply in onto the substrate
with a brush or roller

Wait 2 hours until it fully dries

If you are fixing ceramic tiles on cement or cement lime substrate, you can continue 15 minutes just after priming

CT 17 PROFI - Deep penetrating,
fast drying primer

Formulation for surface strengthening
of all absorbent substrates


  • for all absorbent substrates
  • strengthens the substrate surface
  • reduces substrate absorbency
  • improves adhesion to the substrate
  • application of tiles on cement and cement-lime substrates after only 15 minutes
  • yellow colour — allows to control work phases
  • vapour permeable
  • very low emission EC1
  • facilitates application of subsequent layers of, e.g., adhesives, fillers, putties, floors

CT 17 packshot
CT 17 packshot

Ceresit CT 17 Profi is designed for priming substrates (walls, floors, ceilings) inside and outside buildings prior to fixing ceramic tiles, pouring floors, fixing floor lining, papering, puttying, painting, or fixing thermal insulation boards. The primer is solvent-free. Substrates primed with Ceresit CT 17 Profi (all kinds of plaster, concrete, screeds, primers with underfloor heating installations) are of lower absorbency, which prevents too rapid overdrying of adhesive mortars, flooring, putties and paints.


Product Range