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Technical Dayta Sheet Compedium

CONTENTS CONCRETE REPAIR CORROSION CONTROL GROUTS & ANCHORS PROTECTIVE COATINGS INDUSTRIAL FLOORING SURFACE TREATMENTS JOINT SEALANTS CONCRETE JOINTING JOINT FILLERS WATERPROOFING WATERSTOPS ROOFING TIMBER FLOORING ALPHABETICAL INDEX If spray applying, the concrete surface should be saturated for up to 24 hours prior to application and then any excess water removed from the surface. The Renderoc G can then be applied straight on to the concrete surface without a primer. Mixing Care should be taken to ensure that Renderoc G is thoroughly mixed. A forced-action mixer is essential. Mixing in a suitably sized drum using an appropriate spiral paddle such the Protool HS2 140 x 600 M14 Helical mixing paddle (product code: TT-614217) or equivalent at a slow speed (400/500 rpm) using a heavy-duty mixer, 1500W such as Protool MXP 1602 E (product code: TT-621941) or equivalent is acceptable for the occasional one-bag mix. Free-fall mixers must not be used. Mixing of part bags should never be attempted. For normal applications, place 3.0 - 3.2 litres of drinking quality water into the mixer and, with the machine in operation, add one full 20 kg bag of Renderoc G and mix for 3 to 5 minutes until fully homogeneous. Note: In all cases Renderoc G powder must be added to water. Application Exposed steel reinforcing bars should be firmly secured to avoid movement during the application process as this will affect mortar compaction, build and bond. Apply the mixed Renderoc G to the prepared substrate by gloved hand or trowel. First, work a thin layer of the mortar into the primer and then build the mortar on to this layer. Thoroughly compact the mortar on to the primed substrate and around the exposed reinforcement. Renderoc G can be applied in sections up to 40 mm thickness in vertical locations and up to 30 mm thickness in overhead locations in a single application and without the use of formwork. Thicker sections should be built up in layers but are sometimes possible in a single application depending on the actual configuration of the repair area and the volume of exposed reinforcing steel. If sagging occurs during application, the Renderoc G should be completely removed and reapplied at a reduced thickness on to the correctly re-primed substrate. Note: the minimum applied thickness of Renderoc G is 10 mm. Thicker applications can always be achieved by spray application. Please contact Parchem for further details of this application method. Spray application Renderoc G can be applied by the wet spray technique. In circumstances where large areas of repair are required, the rapid placement and higher build attainable by this method offer economic advantages over hand-trowelling. The resultant repair also offers a generally more dense compound with greatly enhanced mortar/substrate bond characteristics. For further details on the wet spray technique, including selection of spraying machines and nozzles, consult the Renderoc Wet Spray Application Guide available from your local Parchem sales office. Finishing Renderoc G is finished by striking off with a straight edge and closing with a steel float. Wooden or plastic floats, or damp sponges may be used to achieve the desired surface texture. The completed surface should not be overworked. After spray application, the mortar may need to be ‘cut back’ to the required profile using a steel float and then finished with damp sponges as described above. Wetting the surface down before set has occurred can cause a white layer to form on the surface of the repair. Low temperature working In cold conditions down to 5°C, the use of warm water (up to 30°C) is advisable to accelerate strength development. Normal precautions for winter working with cementitious materials should then be adopted. The material should not be applied when the substrate and/or air temperature is 5°C and failing. At 5°C static temperature or at 5°C and rising, the application may proceed. High temperature working At ambient temperatures above 35°C, the material should be stored in the shade and cool water used for mixing. Curing Renderoc G is a cement-based repair mortar. In common with all cementitious materials. Renderoe G must be cured immediately after finishing in accordance with good concrete practice. The use of Nitobond AR, sprayed on to the surface of the finished Renderoc in a continuous film, is recommended. Large areas should be cured as trowelling progresses (0.5 m² at a time) without waiting for completion of the entire area. In fast drying conditions, supplementary curing with polythene sheeting taped down at the edges must be used. In cold conditions, the finished repair must be protected from freezing. Cleaning Nitobond AR and Renderoc G should be removed from tools, equipment and mixers with clean water immediately after use. Cured material can only be removed mechanically. Equipment used with Nitoprime Zincrich and Nitobond EP should be cleaned with Solvent 10. Page 2 35 Fosroc® Renderoc G


Technical Dayta Sheet Compedium
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