How to repair external render

How to repair external render with Blue Circle Cement

When repairing external render using Blue Circle Cement, we recommend the following steps. This advice is designed to offer a general guide to help you create a strong and durable base for your patio.


2+ hours


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Safe working

Working safely on any project is the most important thing. Here are a few tips to keep you safe.

Ensure you have the 'hands-on' skills to take on the project

Always read the label on the product packaging before starting

Always follow the product safety guidance before starting

Ensure you have the correct protective clothing for the job

Always be visible in your workspace

Materials and tools required for this job:

Blue Circle Extra Rapid Cement

Sharp sand



Mixing board


Stiff brush


Plastic sheeting

Safety gear

Online guide: How to repair external render

Remember to follow safety guidelines and wear appropriate protective gear, including gloves and safety glasses, when working with cement. Additionally, always check and follow the specific instructions provided by the Blue Circle cement manufacturer. Using our guidance is your own responsibility.

Step 1

Prepare the Area
Clean the area by removing loose render and dust using a stiff brush. Dampen the area with water.

Step 2

Mix the Mortar
Mix a ratio of one part Blue Circle Extra Rapid Cement and five parts sharp sand with water to achieve a stiff consistency

Step 3

Make the Repair
Use the trowel to place the mortar well into the repair area to fill the void and match the surrounding surface.

Clean your tools promptly after finishing to prevent any material from hardening on them.

Step 4

Allow the repaired render to dry completely for at least 7 days before painting.

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