Over the centuries, renders have been applied to the exterior walls of buildings as diverse as ancient Roman temples, pristine white homes on Greek Islands, quaint cottages in leafy English villages, and even smart, contemporary houses in modern urban settings like Great Ouseburn.
In each case, the render performs a similar job; protecting the building from the elements, providing insulation and prolonging the life of the substrate beneath.
However, there are several different types of render mix, each with its own unique benefits and uses. Traditional sand and cement rendering is one of the oldest and has been in use since at least the Roman era.
At Render Hero in Great Ouseburn, our specialist plasterers are trained to apply every type of render, including the sand and cement variety.
If you're unsure which render type is best for you, we'll discuss the advantages of sand and cement render and explain the application process to help you decide.
As the name implies, it's a basic mix of cement, sand, and water. This forms a thick mortar that is applied to walls to protect them from the elements.
If necessary, hydrated lime and waterproofing agents can be added. Lime makes the mix creamy and more elastic, preventing it from crumbling as it cures, and a waterproofing agent keeps the mix workable for longer, so it doesn't dry out too quickly while being applied.
Lime also fills in any hairline cracks and is breathable, allowing moisture to evaporate from the wall surface naturally.
The type of sand is important, too, as some are not suitable. Building sand, for example, isn't always the best choice, but sharp sand (also called coarse sand or plastering sand) is ideal for the job.
Every experienced plasterer will have their own suggestion as to the 'perfect' ratio for the mixture, although, in reality, this varies according to different scenarios and conditions.
However, as a general rule, a 6:1:1 mix of sand, cement and lime (if it's required) is a popular choice for sand and cement renders. Our rendering specialists in Great Ouseburn will alter the ratio depending on which coat is being applied.
Sand and cement render is best suited for use on a stone or brick wall construction. While it's generally fine on concrete blocks, smooth concrete can present problems with bonding.
Render can be applied over existing render surfaces, but only if they are in excellent condition. All surfaces must be clean and free from loose debris, organic growth, and damaged materials.
For traditional cob walls, lime render is a better match as cement mortar would trap moisture in the substrate.
Sand and cement render is a popular choice for rendering exterior walls in Great Ouseburn, offering a multitude of benefits and advantages for homeowners and building projects:
Sand and cement renders form a robust, weatherproof layer that protects the underlying walls from the elements. It shields against rain, wind, sun, and frost damage, extending the lifespan of the building structure.
With proper maintenance, a well-applied sand and cement render can last an average of 30 to 50 years.
Compared to some other exterior wall finishes, sand and cement render is a relatively inexpensive option. The readily available materials and straightforward application process contribute to its budget-friendly nature.
Sand and cement render offers a degree of flexibility in terms of aesthetics. It can be finished to a smooth or textured surface, depending on the desired look. Additionally, the render can be painted in a variety of colours to complement the overall property design.
Once cured properly, sand and cement render requires minimal ongoing maintenance. Unlike some materials that may need frequent cleaning or repainting, render offers a long-lasting, low-maintenance solution.
However, it’s best to clean your render once or twice a year to keep it in good condition.
Like most renders, this option can contribute to a building's thermal efficiency. The additional layer acts as a slight insulator, helping to retain heat in winter and keep the interior cooler in summer. This can potentially lead to reduced energy consumption for heating and cooling.
This render system possesses inherent fire resistance properties that can be a valuable safety benefit, particularly in areas with stricter fire safety regulations.
While no material is entirely immune to cracking, sand and cement render, when mixed and applied correctly, offers good resistance to cracking compared to some other finishes. The inclusion of lime in the mix can further enhance this benefit.
As with all traditional renders, this option offers a timeless elegance for external walls. Its simple, clean lines can enhance the architectural features of a building, while the subtle variations in texture add visual interest. Whether finished smooth for a modern look or textured for a more traditional feel, sand and cement render's versatility allows it to complement a wide range of property styles. Additionally, the ability to paint the render in a variety of colours means you can personalise the aesthetic to perfectly suit your taste and create a truly unique façade for your home.
Before any work begins, we conduct a thorough inspection of the substrate (wall surface). This includes identifying and addressing any loose brickwork, damaged mortar joints, or significant cracks. We will employ appropriate remedial measures such as repointing or crack stitching to ensure a sound base for rendering.
The substrate will be thoroughly cleaned with wire brushes to remove dust, dirt, loose particles, or traces of paint. A pressure washer may be necessary for heavily soiled surfaces to ensure the final rinse removes any cleaning product residue.
Immediately prior to rendering, the substrate will be lightly dampened with clean water using a sprayer. The damp surface creates a slightly absorbent surface that promotes optimal adhesion between the render and the substrate.
The work area will be cleared of furniture, landscaping, and any other potential obstructions. Drop cloths or sheeting will be used to protect surrounding areas from material splatter.
Where the render meets window or door frames, galvanised metal beading will be installed to establish a straight edge and provide additional reinforcement to prevent cracking.
Although it's a sand and cement render, sand forms the greater part of the mix. A typical starting point involves a 4:1 or 5:1 ratio (by volume) of sharp sand to Portland cement. Hydrated lime at a 1:1 ratio with cement is often recommended to enhance workability and render elasticity, minimising the risk of cracking.
It takes skill to get the correct mix, and our experts know which factors influence this, such as weather conditions, application method, substrate and desired finish.
A cement mixer is used to thoroughly churn the rendering mix until it is ready for application.
The first layer, known as the scratch coat, will be applied using trowels. This provides a key for the subsequent finishing coat to adhere effectively. This thin coat will be pressed firmly onto the substrate, and while the surface needs to be level, a rendering comb (or trowel) is used to score the surface of the render to create a better bond with the top coat. It will then be allowed to cure for a designated period, typically 24-48 hours, depending on weather conditions.
Once the base coat has cured and is firm to the touch, the next coat will be applied. This render mix may be slightly weaker than the scratch coat to improve workability and achieve a smoother finish. The render will be applied with trowels and levelled using a rendering float to ensure a uniform surface.
If a textured appearance is desired, the render can be manipulated at this stage using tools like sponges or specialist textured trowels. This should be completed before the render stiffens to achieve the optimal effect.
It comes down to personal preference; some clients prefer a beautiful, smooth finish, while others prefer the textured look of a sponge finish.
Following application, the render will require a period of curing. For several days, the surface will be protected from direct sunlight and adverse weather conditions with breathable shading. This prevents the render from drying out too rapidly, which can lead to cracking.
Upon completion of the curing period, the site will be thoroughly cleaned. Any masking or protective coverings will be removed, and the rendered surface will be inspected for any imperfections. Minor blemishes can be addressed at this stage.
The client will be provided with aftercare recommendations to ensure the longevity of the render. This may include advice on avoiding high-pressure water cleaning methods and potential redecoration cycles.
It's wise to consider a regular cleaning and maintenance schedule, although it should stay fresh and clean for a few years. At Render Hero in Great Ouseburn, we offer a first-class render cleaning service that keeps your walls looking fantastic!
When choosing the type of render you want, you need to take into account the condition of your walls, the age of the property and the building materials involved. You also need to consider what kind of finish you want, and whether the render mix needs to be more breathable, waterproof or crack-resistant.
For example, lime render is perfect for older buildings without cavity walls, as it is flexible and breathable. And while it has great water resistance, acrylic render lacks the breathability of lime.
Through-coloured render is also available, so there's no need to paint it, while sand and cement render
This can make it difficult to know which one is the best choice!
Never fear; Render Hero will guide you all the way. We'll inspect your walls, discuss the various options, and suggest the ideal render for your circumstances.
Our specialists will then upgrade and enhance your property with a stunning new coat of beautiful render.
Applying render isn't as easy as it might sound!
To begin with, you need the best sand and good-quality cement, which aren't always available from local builders' merchants (at least, not to the general public).
Next, you must get the right mix ratio of sand, cement, lime (if using), and water. For the uninitiated, getting the best mix can be a matter of trial and error, leading to wasted time, money, and materials.
Then the render must be applied properly, which requires a skilled hand. The trick is to get the sand/cement mix onto the walls and achieve a flat finish using a wooden float before the render dries out. And don't forget - the base coat needs to be scratched before the mixture dries!
Getting a perfectly smooth surface isn't easy, and even a textured finish needs an element of skill. You'll also need to apply the render in very thin coats of no more than 20mm, maximum.
Many DIYers end up making too many trips to the cement mixer and back again with a trowel full of render, rather than using a hawk. Others find - too late - a mass of unmixed sand at the bottom of the cement mixer, meaning that the render mix isn't right.
So, unless you're pretty experienced, always seek advice from a professional builder or plastering specialist. Better still, call Render Hero, and we'll handle all the hard work for you!
At Render Hero, we take pride in transforming your house exterior with high-quality, long-lasting sand and cement render. Our team of skilled and certified professionals possesses the expertise to ensure a flawless finish that complements your property's style.
Whether you require a classic smooth render or a textured finish for a unique look, we can advise you on the best materials and techniques to achieve your vision. We use only top-grade sand and cement mixes, ensuring a render that's not only beautiful but also protects your walls from the elements for years to come.
Ready to breathe new life into your façade? Contact the Render Hero Great Ouseburn team today for a free quote and consultation. We'll discuss your project requirements, answer any questions you may have, and guide you through the entire process, ensuring a stress-free experience from start to finish.