Sika Sikagard 720 EpoCem

Sika Sikagard 720 EpoCem is a three part, epoxy modified cementitious, thixotropic, fine textured mortar for levelling and finishing of concrete, mortar or stone surfaces. Class R4 Approved.

Best Uses

Sika Sikagard 720 EpoCem is formulated as a levelling layer over concrete and mortars in 0.5–3 mm on vertical or horizontal surfaces. It is also ideal for application in new works or damaged concrete, in aggressive chemical environments, and application over high moisture content substrates, even green concrete.

Sika Sikagard 720 EpoCem is also suitable as a Temporary Moisture Barrier (TMB) (min. 2 mm thick) allowing the application of Epoxy, Polyurethane and PMMA* resin coatings requiring dry substrates, for a lasting solution.

Also suitable for:

• As a pore sealer for the reprofiling, smoothing and levelling of concrete surfaces
• Suitable for moisture control (Principle 2, method 2.3 of EN 1504-9)
• Suitable for restoration work (Principle 3, method 3.1 and 3.3 of EN 1504-9)
• Suitable for physical resistance (Principle 5, method 5.1 of EN 1504-9)
• Suitable for preserving or restoring passivity (Principle 7, method 7.1 and 7.2 of EN 1504-9)
• Suitable for increasing resistivity (Principle 8, method 8.3 of EN 1504-9)

Features

• Improved chemical resistance compared to PCC mortar
• Excellent protection of concrete in aggressive environments
• CE marked in accordance with EN 1504 parts 2 and 3
• Impervious to liquids but permeable to water vapour
• Excellent bond to green or hardened concrete whether damp or dry
• Fast overcoating of Sika® resin based finish products
• Ideal preparation for smooth surface finishes
• For internal or external use
• Contains no solvents
• Can be applied by hand or mechanically

Application

The concrete substrate must be sound and of sufficient compressive strength (minimum 25 N/mm2) with a minimum pull off strength of 1.5 N/mm2. The substrate can be damp but must be free of standing water and free of all contaminants such as oil, grease, coatings and surface treatments etc. If in doubt, apply a test area first.

Concrete substrates must be prepared mechanically using abrasive blast cleaning or scarifying equipment to remove cement laitance and achieve an open textured
surface. Weak concrete must be removed and surface defects such as blow holes and voids must be fully exposed. Repairs to the substrate, filling of blowholes / voids and surface levelling must be carried out using appropriate products from the Sikafloor®, Sikadur® and Sikagard ® range of materials. All dust, loose and friable material must be completely removed from all surfaces before application of the product, preferably by brush or vacuum.

MIXING
Prior to mixing, shake part A (white liquid) briefly until homogeneous, then pour into the container of part B and shake vigorously for at least 30 seconds. When dosing out of drums, stir and homogenise first. Pour the mixed binder (A+B) into a suitable mixing container (capacity of about 30 litres) and gradually add part C while stirring with a power mixer. Mix thoroughly for 3 minutes until a uniform mix has been achieved, with no lumps. Mix only full units of A+B+C components. Do not mix smaller amounts. Do not add water.

Mixing Tools
Mix using a slow speed electric mixer (300 - 400 rpm) with helical paddle or other suitable equipment. For mixing 2–3 bags at once, single or counter rotating
double mortar (basket type) and forced action (pan type) mixers are also suitable. Free fall mixers must not be used.

APPLICATION
Hand application:
Place mixed Sikagard®-720 EpoCem® onto the matt damp substrate and spread evenly to the required thickness with a trowel or spatula. If necessary, it may be finished with a moist neoprene sponge or brush.

Mechanical Application:
Placement on to the surface can also be done using a hopper gun or wet spray technique. For example an Aliva Hopper gun, a Putzmeister S-5 or a Graco T-Max
405. Subsequent finishing by hand is required. Do not use additional water, which would disturb the surface finish and cause discolouration. Freshly applied Sikagard®-720 EpoCem® must be protected from rain for at least 24 hours.

Once Sikagard®-720 EpoCem® is tack free it is possible to apply vapour permeable seal coats. Always verify that surface moisture < 4 % when applying vapour
tight coatings. A seamless finish can be achieved if a “wet” edge is maintained during application.

Note:
Sikagard®-720 EpoCem® can be applied on green or damp concrete, without any standing water. Although the product can be applied onto green concrete surfaces (> 24 hours), it is advised to allow at least 3 days for early shrinkage of concrete to occur in order to prevent concrete shrinkage cracks from appearing on the screed / render surface.

Sikagard®-720 EpoCem® is part of the extensive range of Sika Products available from Promain.