Tools you will need:
- Metal trowel
- Wooden trowel
- Polystyrene float
- Plasterers hawk
- Steel brush
- Soft brush
- Tape measure
- Measuring jug
- Masking tape
- Access to clean water
Follow these simple step-by-step instructions to render a brick or block wall with Cement Australia Render It™ Multisurface.
Basics of how to render a brick wall
Tools you will need:
Materials you will need:
If multiple batches of render are required to complete your job, it is worthwhile considering using a heavy duty drill and stirring attachment to make mixing easier and more consistent across batches.
For an easy-to-use, one part render mix we recommend Cement Australia Render It™ Multisurface Grey.
Before you begin any project, please ensure you protect yourself with the following:
Using a steel brush remove any paint, laitance, plaster or any other loose material that may prevent good adhesion. Remove any brittle mortar in the joints of brick or block walls.
To protect the area from spilt render, cover paths or driveways with black plastic sheets and mask any other exposed surfaces you wish to keep clean.
Fix the corner beading to the external corners of the surface to be rendered using an approved adhesive ensuring the beading is straight and plumb to provide a neat rendered finish. You can use Render It™ Multisurface to attach the beading to the external corner if you don't have an approved adhesive available. Apply a small amount of render to the inside of the beading, press it firmly to the corner and clean off the excess render that is squeezed out.
Thoroughly wet the surface to be rendered with a hose on a light spray setting or using a wet brush.
If you are rendering a new brick or block wall ensure that the mortar has been cured for at least 7 days to prevent hairline cracks from appearing in your rendered surface as the mortar dries.
Only mix one bag of Render It™ Multisurface at a time.
Add 4 litres of clean water to a wheelbarrow and slowly pour one bag of render into the water. Mix thoroughly ensuring that the render is lump free and is stiff so that it will sit on a trowel. Allow the mix to stand for 5 minutes so that the polymer chemicals are activated and then quickly stir the mix again. Render It™ needs to be applied within 30 minutes of final mixing and any spilt render should be discarded.
A heavy duty drill mixer is recommended for large rendering jobs providing a more consistent mix, where manual mixing in a bucket or wheelbarrow is suitable for smaller projects.
If you are rendering an existing brick or block wall, work the render into the mortar joints to provide a relatively flat surface.
Start at the bottom of the surface to be rendered and apply the render with a steel trowel in an upward pushing motion. Ensure that you use long, even spreads upward and across the surface achieving a consistent and even thickness. Fill any holes or divots with the render as you go. Do not overwork the surface as too much fine material will be brought to the surface increasing the likelihood of crazing (fine cracking).
Render It™ Multisurface can be applied in a thickness ranging from 2mm to 10mm in a single application. If subsequent coats of render are to be applied, the surface should be raked or scratched within 30 minutes of application to provide a rough surface to aid the adhesion of any subsequent coat. A minimum of 3 days must be left between coats to allow the render to develop maximum strength and prevent shrinkage cracks.
Allow the final layer of render to become firm and finish off with a wooden trowel or polystyrene float to smooth and then finish the surface to the desired texture.
To achieve a different texture a damp sponge can be used to provide a swirl or use a fine brush to provide a swept finish ensuring that not too much pressure is applied to damage the rendered surface.
If these techniques are not giving you the definition you want in your finish, wait until the render becomes firmer and finish the surface again.
To prevent cracking, keep the rendered surface moist by spraying it with a mist spray 24 hours after the wall is finished and repeat this for 5 days.
Where the newly rendered surface is in full sun, it is vital to cover the surface to prevent rapid moisture loss. Failure to do so could result in cracking. If using plastic sheeting to cover the render, prevent the plastic from touching the surface as contact may lead the rendered surface to be damaged or discolour unevenly.
The rendered surfaced can be painted with water based paints after 14 days or after a minimum of 28 days where oil based paints are used.