3.1 Check and Prepare Masonry / Clay brick veneer Substrate
Preparation based on new substrate installations.
2.2.1. Preliminary Checks
Check all exposed surfaces of the substrate are straight, plumb and undamaged. Any loose bricks identified must be removed and replaced. Ensure pointing has cured according to the manufacturer’s specifications prior to render application.
2.2.2. Wall Alignment
Using a straight edge, check joints are smooth and that the wall is flat and true. The Render coating is not designed to straighten deviations which exceed the specified Rockcote Render System thickness.
2.2.3. Weep Holes
Weep holes must be kept clear of Render unless an alternative solution is accepted by the BCA.
2.2.4. Builder Supplied Flashings
Make sure all builder supplied flashings are in place. (Refer to Rockcote TradeSpec™ document 3.2 Builder Supplied Flashings) for a list of possible builder supplied flashings.
2.2.5. Rockcote Flashing Installation
Refer to the flashings as outlined within the Rockcote RenderSpec™ section 5 and refer to their installation procedures in Rockcote TradeSpec™ Document 3.1 Rockcote Flashings
2.2.6. Control/Expansion Joint Set outs
for more information about control joints refer to TradeSpec™ Document 1.4 – Control Joints
Control joints shall be included at locations specified by the brick manufacturer.
Control joints shall be included as specified in the New Zealand Concrete Masonry Manual and in any other locations specified by the brick manufacturer.
2.2.7. Clean Surface
When the substrate has been left for a period of time, dust and dirt may build up on the surface. This contamination must be removed prior to render application.
Before application of Render, apply masking to all joinery, pipes, roofs and all areas likely to be marked by the Render. Use drop cloths and ground covers to keep the working areas clean.
2.2.9. Improve adhesion
If Rockcote Render is being applied to the masonry wall, wet the wall down, or apply a solution of Rockcote Acrylbond and Water – ratio1 part Acrylbond : 4 parts water to minimise the suction of the substrate.
Allows the render to maintain moisture content for longer, providing greater working time. This process assists with the initial hydration / curing of the render application.
2.2.10. Colour selection
For further information on Light Reflectance Values (LRV) refer to TradeSpec™ Document 1.6 – Light Reflectance Values