Base requirements and coating conditions
The strength class of the concrete must be at least C25/30 and the wear resistance class 3. The relative humidity of the concrete must be below 98%, and the surface temperature must be at least +3 °C above the dew point. During application and curing of the coating, the air, surface, and coating temperatures must be above +15 °C, and the relative humidity of the air must be below 80%.
New concrete floor
Cement laitance and any uncured cement must be removed by surface grinding, shot blasting or milling. All loose and adhesion-reducing materials must be removed, and cement dust must be thoroughly vacuumed.
Old concrete floor
Cement laitance and deteriorated concrete must be removed by grinding, shot blasting or milling. All loose material that could negatively affect adhesion is removed, and the base is carefully vacuum-cleaned. Dirty floors should be washed and rinsed with synthetic detergent before performing any other base treatment work. Any old coat is removed completely.
Patching work
Small cavities and cracks are cleaned and filled with e.g. epoxy paste mixed from Nanten HM Bio and fine back sand. Larger and wider overfills, straightening and slopes can be made with a compound made of HM Bio and back sand (0.1–0.6 mm).
Mixing
Premix component A and component B of M Primer in separate containers, estimate the required amount of compound, taking into account the size of the area to be treated and application time of the compound. Mix the components together in the right mixing ratio, mix with a slow-speed mixer for approximately three minutes, avoid mixing air into the compound.
Mixing ratio
Part A: 2 parts by volume
Part B: 1 part by volume
Spreading rate
Depending on the porosity of the concrete, 0.25–0.35 l/m².
Porous surfaces may require a second application to ensure all pores are sealed and a uniform, continuous film is achieved.
Application instructions
The mixed M Primer should be poured onto the floor in a continuous ribbon and spread using a rubber squeegee. Apply a second coat crosswise after approximately 1–2 hours when the surface is tacky, but no later than 24 hours after the initial priming. If the surface is to be coated with a trowel-applied topping, broadcast adhesion sand onto the primer to improve the flow and adhesion of the topping. Ensure proper ventilation in the working area. The primer must seal all pores in the concrete to form a dense, tight, and continuous film. Do not scrape or use material left on the container walls.
Storage and handling of waste
See the separate storage and disposal instructions https://www.fescon.fi/en/material-bank