3.3 Check and Prepare ICF Substrates

Preparation based on new substrate installations.

2.4.1. Preliminary Checks

It is the builder’s responsibility to ensure the ICF structure is set out true in the correct alignment, as required by the Designer. Before Rendering, check that timber blocking is provided to support any external fittings where required, e.g., around all openings, at soffits, at joints, and at internal corners.

A check should be made using a straight edge to ensure the wall is flat. Any irregularities should be taken out by straightening using a rasp.

2.4.2. Wall Alignment

Using a straight edge, check joints are smooth and that the wall is flat and true. Builder to re-align ICF if incorrect. If straightening is completed using Render additional costs may be incurred.

2.4.3. 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.

2.4.4. Liquid membrane flashings to openings

(Refer to 3.3 Liquid Membranes – Masonry and ICF Block

2.4.5. 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

2.4.6. Control/Expansion Joint Set outs

for more information about control joints refer to TradeSpec™ Document 1.4 – Control Joints.

2.4.7. Clean Surface

If the substrate has been left exposed to UV / sunlight for more than two weeks, dust and dirt may build up on the surface, the surface may also discolour (yellow) you must remove all surface dust, oxidisation, and other contaminants to reveal fresh polystyrene. Use a rasp or a stiff broom to prepare the substrate.

2.4.8. Masking

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.

2.4.9. Colour selection

For further information on Light Reflectance Values (LRV) refer to TradeSpec™ Document 1.6 – Light Reflectance Values