Everything You Need to Know About Cement Render - ANB Cement Rendering Pty (sydneycementrendering.com)

Cement render is the most common type of render you will find across Australia, and for good reason: it provides a timeless classic look, can be used on both exterior and interior walls and is relatively inexpensive compared to other render types.

Continue reading to learn more about cement render.

What is Cement Render?

Cement render is a mixture of cement, sand, water, and lime that is applied to surfaces such as brick, concrete, and stone. It not only provides aesthetic benefits, but also has many functional and protective properties.

Cement render has been used for many years and is one of the most common renders you will find on homes across Australia.

The Cement Render Mixture

Getting the cement render mixture just right is incredibly important and plays a large role in its strength, durability and appearance. Even the tiniest mistake or a slightly off mixture ratio can throw the whole render project off kilter.

Each component of a cement render has an important role to play:

Cement: Cement keeps all the components of the render mixture together, acting as a binding agent.The quality of the cement used determines the render’s strength. Most professional rendering companies use General Purpose (GP) Ordinary Portland Cement, a versatile, high-quality, cost-effective cement that is used for a wide range of construction and renovation projects.Another commonly used type of cement is Portland cement (OPC), one of the most widely used worldwide and known for its versatility, strength, and durability.
Sand: The grain size of the sand used impacts the layers and thickness of the render. If the sand grain is too fine, the render mix may become too dense, while a coarser grain may result in a messier, more uneven appearance.The best sand for cement rendering is either clean, sharp sand, which provides strength, or washed plastering sand, which results in a smoother finish.
Lime: Lime is added to cement render to improve its flexibility, durability, and strength, and to reduce the risk of cracking. It also provides better adhesion.Once the lime is added to the cement render mixture, it becomes smoother and easier to apply to surfaces.
Water: Clean and drinkable water should be used in the render mixture. Add enough water to create a soft and putty-like consistency.

The ratio of each component can determine the strength, functionality, and durability of the cement render mixture.

Cement Render Mixture Ratios

Different Cement Render Mixtures		Result
Standard Cement Render Mixture	4 or 5 parts sand. 1 part cement Water to create a soft mixture	Results in a strong and slightly flexible render mixture that withstands various weather conditions
Stronger Cement Render Mixture	3 parts sand 1 part cement Water to create a usable paste	Results in a stronger render mixture, but may also be more prone to cracking.
Thin Cement Render Mixture	5 or 6 parts sand 1 part cement Enough water to create a workable paste	A more flexible cement render, but weaker than other ratios. Works well on interior surfaces.

The Benefits of Cement Render

Aesthetics

Sick of your home’s boring and tired-looking appearance? Add cement render to the exterior and watch it transform into a clean, classic, and elegant-looking home.

Increased Property Value and Curbside Appeal

Cement rendering can instantly increase your home’s property value and curbside appeal. This is a huge benefit if you plan on selling your home one day in the future.

Improved Insulation

Cement render adds extra layers of insulation to your home, helping to keep indoor temperatures consistent. It minimises heat absorption during the summer months and prevents heat loss during winter. Better-controlled temperatures can significantly lower your energy and electricity bills.

Durability

When the cement render mixture is of high quality, it can last for years, adding a protective layer to your home.

Water-Resistance

Cement render has excellent resistance to water absorption and moisture, reducing the risk of mould and fungal growth, structural damage, and dampness.

Low Maintenance

Cement render is relatively low-maintenance and should be cleaned once or twice a year, and repainted if required, to revitalise its appearance.

Cost-Effiveness

Compared to modern render types like silicone- and acrylic-based renders, cement rendering is more cost-effective and affordable than most other render options.

Versatile Finishes

Cement render can be coloured or have patterns and textures applied to it, making each render job unique and your own.

The Disadvantages of Cement Render

Higher Risk of Cracking

Perhaps the biggest disadvantage of cement rendering is its higher risk of cracking due to its rigidity. Compared to other render types, it is unable to effectively withstand the natural movement of the structure over time.

Longer Curing Time

Cement render can take up to 28 days to fully cure and dry. One of the longest curing times for any render type. This is especially disadvantageous in unpredictable weather conditions, which can negatively impact the rendering process.

The Process of Applying Cement Render

It is recommended that rendering jobs be completed by professional renderers. However, the overall process is fairly easy to carry out yourself, as long as you prepare well, use the correct render mixture ratios and apply the render during a mild day (not too hot and not too cold).

The general process for applying cement render includes:

Step 1: Ensure your skin and eyes are protected with safety glasses, gloves, and protective overalls, as the rendering mixture can cause burns to exposed skin and eyes.
Step 2: Use a hose or a stiff brush to remove any debris, plaster, or loose materials from the surface. Any paint or rendering will need to be scraped away, while an anti-fungal solution will need to be applied to remove any mould. If this is not done, then the mould will continue to grow. It’s also a good idea to remove old, brittle mortar between the bricks.
Step 3: Apply angle beads around any windows or doors to ensure the render has smooth edges.
Step 4: Protect the surrounding area from render mixture spillage by covering the driveway, paths, and the ground with sheets, and any other surfaces you want to keep clean.
Step 5: Before applying the rendering, read the instructions carefully, as every rendering product has different instructions and drying times. Mix the render materials well so that there are no lumps. Let the mixture stand for a few minutes and then mix it again. Apply the render to one section of the wall at a time, starting at the bottom and working your way up with an upward push of the trowel, making sure to smooth the render out as much as possible.
Step 6: If you’re applying more than one coat of render, it’s important to let each coat dry for about a week before applying the next one.
Step 7: After the last layer has been applied, you can finish the look by using different decorative techniques, which can include a sponge finish (sponging the surface with a damp sponge), a patterned finish (rubbing a ball of wet hessian into the surface) or a roughcast finish (throwing the final coat onto the wall, which creates a rough finish).

Once the rendering has completely dried, spray it with a fine mist of water to prevent any cracking.

The rendered wall can be painted with water-based paint 4-8 weeks after it has fully cured and dried.

At Sydney Cement Rendering, we take pride in being Sydney’s trusted rendering experts. We provide our customers with the highest quality rendering services. To learn more about cement rendering, contact us at 0402 704 984 or visit our website https://sydneycementrendering.com/ to find out more about the services we offer!