Here at Artisan Plastercraft, we are dedicated to providing advice and assistance wherever possible. This includes helping our customers to make an informed decision on the products and materials they are ordering for their properties. As part of our assistance, we have created this guide on lime render, allowing you the opportunity to learn more about a material that may soon transform the walls and columns of your own planned project.
Read on to learn more about what lime render may provide, or contact us to discuss your building and restoration work if you already know what you need.
What is Lime Render?
Lime render is noted to be the base coat of lime plaster, or other similar materials (particularly lime products). When specialists work with the material as a render, it will be applied to the external surfaces of traditionally-built stone or brick buildings. It may also be referred to as lime plaster when used in an interior space.
How is Lime Render Made?
The material itself is made from a specific mix ratio of water, lime, and sand. In most cases, the lime used in the preparation will be non-hydraulic hydrated lime. This may also be called slaked lime, high calcium lime, or air lime. Under some circumstances, you may also see it referred to as lime putty.
A traditional lime-based render will dry slowly after application, absorbing natural carbon dioxide from the air in the presence of moisture. As such, each coat of lime render used may take between 1 and 3 days to dry initially, depending on external temperatures and the weather in general. After this, it may take weeks for the finished coats to set, and up to a year to harden completely.
It is also important to note that lime render for exterior projects should only be applied in temperatures above 5°C.
Lime Render Colours
Lime render is available in a myriad of colours to suit the needs and tastes of the property owner or manager. Most material varieties are available in natural stone colours and shades to offer a traditional aesthetic. This also means they are ideal for revitalising and restoring any heritage building which requires work on its original façade. However, you may also come across shades and colours to suit a more modern build with a contemporary shade planned for its walls.
What is the Difference Between Lime and Cement Render?
The most basic difference between cement and lime renders is their chemical composition. Lime as a material is produced from natural limestone, by burning the stone in a kiln until only quicklime (also called calcium oxide) remains. The quicklime is then blended with small amounts of water to create hydrated lime. Cement, on the other hand, is created from a mix of highly reactive silica-containing compounds (including sharp sand).
It may prove difficult to tell lime and cement render finishes apart without specialist insight, though there are some indicative physical qualities that may help you to determine which you are seeing. If the building work you are restoring predates the 1800s, the original finished coats are likely to contain a type of lime render. As an aesthetic finish, cement renders are also more likely to achieve a uniform appearance, with sharper and more defined corners and edges.
Lime and cement renders will also weather differently. Lime is less brittle and not as prone to cracking as cement, and should weather more gradually. This will aid in keeping a structure waterproof. Conversely, cement will often crack, particularly as it settles, and may detach from walls in patches.
Renders made from modern cements are incompatible with the renovation work required for many older and historic properties, particularly original lime rendered houses and public buildings. This is because these properties rely on the permeable nature of lime render to reduce moisture, whereas newer builds may use an impervious cement layer to keep moisture out instead.
If the two are introduced, it is possible that hairline cracks will form and draw in moisture which cannot evaporate. If this is allowed to build, there may be structural damage as a result.
How Long Does Lime Render Last?
Traditional lime render has the potential to last for many years, and may span centuries with the care and attention that the material is owed. This is proven by the fact that many historic buildings, such as older churches and other heritage spaces, have retained a lime-based render that has not been replaced in generations. Some of these places may be in a noticeable state of disrepair, but the presence of lime render at these sites is a testament to the material’s ability to withstand the ravages of time and neglect.
If you intend to apply limewash as a topcoat or finish coat to your lime render, you should be aware that this will have a much shorter lifespan than the render itself. On average, you should seek a reapplication of limewash every 3 to 7 years.
We do not recommend that you use modern paints when finishing any project involving interior or exterior lime render. This is because modern paints have the potential to restrict the render’s function, and may even have detrimental or destructive consequences in the future.
How a Lime Render Mix May Benefit a Property
There are many advantages to applying traditional lime render to the internal or external walls of your property. Naturally, you will wish to learn more about these before applying a mix to any building you own or manage on behalf of someone else. We have created a list of these advantages below, and given a short explanation as to how they will benefit any new or heritage build:
- Lime render offers a property permeability, meaning that the material is “breathable”. This reduces the risk of trapped moisture and subsequent damage to the building fabric
- As the risk of trapped moisture is reduced, a lime rendered house or commercial building will also have a reduced risk of mould growing on the walls or ceiling
The material also offers a waterproof element and water-resistant properties. This allows it to remain strong against potential weather damage when used on external walls and columns
- A lime rendered house or commercial building will be provided with extra insulation
- The manufacturing process of lime render creates less embodied carbon than the process used to manufacture cement render, and the material itself reabsorbs carbon dioxide. This means the material is created at a lower cost to the environment and remains environmentally-friendly
- As it is to be considered an environmentally-friendly material, it has become the in-vogue choice for many contractors and property developers. As such, you will be choosing a fashionable material for your own work project
Contact Us for a Quote on Specialist Lime Render
If you are in need of a reliable, experienced firm that can offer a specialist application of lime-based render to any interior or exterior space, please contact our offices today. We are fully prepared to provide our services for a variety of structure types, from modern commercial lots to heritage properties and listed buildings. Every specification you have in mind will be taken into account and made a priority throughout the process.
We are more than confident that we will be able to provide exactly what you need, at a cost which suits your budget. To ensure this, we will offer you an estimate of the price before our team sets to work on transforming any space you wish to see brought to the zenith of its potential.