Preparation
Use a concrete mix of a minimum of 20 N/mm2 (30 N/mm2 for heavy duty traffic), with a slump of 75 mm or less and maximum 3% entrained air. The design and construction of the floor should be adequate to withstand the traffic, impact and such other loads the floor is likely to be exposed to.
Place concrete and consolidate with vibrators if necessary. Strike off concrete level. Further level and consolidate using a wooden bull float or wooden darby. Complete this operation before any bleed water appears. Remove any bleed water on the surface just prior to floating by dragging a rubber hose over the surface.
First float the concrete surface adjacent to forms, columns, pits, doorways and walls, where the concrete is likely to lose moisture rapidly, using a hard wood or a mechanical float. Float the overall area as soon as concrete can bear the weight of a finisher and a light trowelling machine equipped with float blades without digging in.
Placing
Sikafloor® SynTop-103 should be applied in two layers by broadcasting by hand. Approximately two-thirds of the total quantity should be applied in the first broadcast and the remaining balance in the second.
First shake-on application
Mark the floor area into bays of convenient size and keep the required number of bags of Sikafloor® SynTop-103 ready for each bay, depending on the rate of application specified. If applying manually, transfer the powder to pails of a size convenient for handling. Broadcast the powder evenly by hand, allowing it to sift through gloved fingers to obtain a uniformly thick application, after the evaporation of bleed water. Do not throw or broadcast with a shovel.
After the applied Sikafloor® SynTop-103 darkens in colour indicating absorption of moisture from the concrete and when the concrete has stiffened enough to prevent the float blades from digging into the surface, float the applied surface using wooden hand floats or power floats. Float just enough to bring the excess moisture to the surface.
Second shake-on application
Follow with the second application of Sikafloor® SynTop-103 as the first application proceeds to next bay. Broadcast the remaining third of Sikafloor® SynTop-103 evenly by hand, compensating with extra material over areas under-applied during the first broadcast. As soon as the second layer has darkened by moisture absorption, float the surface with a power trowel equipped with float blades or disc floats. If a coarse non slip surface is desired, start curing without any more finishing operations.
Finishing
The extent of further floating or trowelling depends upon the finish desired on the surface. For obtaining a medium, non slip finish, power float the surface for the third or fourth time depending on the setting characteristics of concrete.
For obtaining a fine non slip finish, trowel the surface after it stiffens further using a hand or power trowel keeping the blades as flat as possible without digging in the surface.
For a superior smooth finish, trowel again after further stiffening of the surface with slightly raised blades, but avoid raising them to an angle that creates chatter marks or blisters on the surface. If either start to appear, remove them by reducing the angle of trowel.
When only a little paste starts clinging to the trowel blade, finish with a final trowelling with raised blades. Remove any pinholes and trowel marks by hand trowel.
Note: During hot, dry or windy conditions, trowelling should be kept to the minimum to obtain the required finish. Start early curing to prevent damage to the floor from rapid drying.
