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What is a "Halo Ring?" It's a renderers nightmare that's what it is! 

Halo rings in render are formed during the scraping process when an applicator unwittingly scrapes through the finish coat to the much harder base coat or first pass resulting in a flat textured area that cannot be matched into the rest of the wall. The worst cases may even go as far to reveal the mesh embedded into the first pass as the below picture shows:

Can they be avoided?

Most renderers I speak to have a story about a halo ring in either K Rend, Parex or other manufacturers mineral renders that caused them real headaches. Whilst we have had some success in correcting them with our Mendrend Render Repair System we cannot guarantee success under all circumstances as they all tend to be different. This is one of the most common issues we are asked to look at and if I'm honest the one we struggle with the most so if we can provide guidance to avoid it in the first place it suits us!

1. Before starting application check the walls with a long straight edge. If any bows or bellies over 3-4mm are present in the substrate then seriously consider the use of a K Rend or Parex base coat instead of just priming to level the walls out ready for the finish coat.
2. If applying a base coat ensure this too is level with a straight edge before applying the finish coat. Ensure that the K Rend or Parex finish coat is applied to a depth of at least 12mm over the top of the base coat to allow 2mm to be scraped with little risk of scraping too much away.
3. If you aren't applying over a base coat and instead applying the finish coat in two passes, do not apply the first pass too thick, we advise the first pass should be around 6mm maximum and level for both K Rend and Parex. The second pass should be at least a further 12mm on top of that applied wet on wet.
4. It is common for suppliers to under estimate the amount of material you will need in an effort to look like they are the cheapest or doing you a favour. They know that you will be straight back on the phone if you are running out of material and trying to get a job done. What generally happens instead is that the inexperienced applicator starts to take risks by spreading thinner. Always ask your supplier to justify the quantities quoted, backed by a manufacturers specification document. It's always better and cheaper to have a few bags left over at the end of the job rather than running out of material. Always ensure you allow 5-10% additional material for wastage on top of manufacturers quoted consumption figures as that doesn't tend to be included. You'll figure out how much you will need to allow for this yourself once you get a feel for the material after using it for a while. 
5. Every applicator uses a slightly different amount of material to the next due to differing working patterns. Keep a record of material consumption over a few jobs to see if you get consumption rates that suit you.

Avoiding this issue is as simple as that! Hopefully you find this of help and avoid the renderers curse in future!

Choosing the right render for a property is about more than just appearance. Factors such as the building substrate, exposure to weather, maintenance requirements and overall performance should all be considered before selecting a render system.

Modern render systems are available in a wide range of colours, textures and finishes, with each offering different benefits depending on the project requirements. From traditional sand and cement render through to modern breathable render systems, choosing the correct product can have a significant impact on both the appearance and long-term durability of a building.

One of the most important considerations when selecting a render is breathability. Breathable render systems are designed to allow moisture vapour to escape from the wall structure while still protecting the surface from rain and weather exposure. This can help reduce trapped moisture and minimise issues such as cracking, staining or damp-related damage over time.

For older properties or buildings with solid wall construction, breathable render systems are often preferred due to their ability to manage moisture more effectively. Modern silicone render systems are also popular thanks to their flexibility, water repellency and low-maintenance finish.

Monocouche render remains a widely used option for both residential and commercial projects. As a self-coloured render, it provides a durable decorative finish without the need for regular painting, making it a practical long-term solution for external wall rendering.

The texture and finish of the render should also be considered carefully. Smooth, scraped and textured finishes can all dramatically change the appearance of a property, while different application methods can influence the final look and performance of the system.

Building location can also play a role in choosing the right render. Properties exposed to coastal conditions, heavy rainfall or pollution may benefit from render systems with enhanced water repellency and dirt resistance.

Ultimately, choosing the right render comes down to balancing aesthetics, performance, maintenance and suitability for the substrate. Seeking professional advice can help ensure the selected system is appropriate for both the property and the environment it is being applied to.

Whether you are renovating an existing property or working on a new build development, modern breathable render systems provide a reliable and attractive solution for long-term exterior wall protection.

I regularly hear people proclaim that their monocouche or through coloured scraped renders are "non-maintenance," and they are often a little flabbergasted when they are told that their render needs cleaning. This is a common misconception and usually comes down to a misunderstanding of what "non-maintenance" actually means.

Modern renders are incredibly hard wearing; a correctly applied system will withstand many years of whatever the elements throw at them, even in extreme circumstances. I drive past a rendered property that was rendered nearly 30 years ago which, despite being subject to heavy flooding (over 8ft deep at numerous points), still looks great today with no sign of the render failing anytime soon.

On that basis, modern renders are certainly expected to be low-maintenance. Once installed correctly, you'll have a hell of a time removing them, and re-applying within the next couple of decades should not be necessary.

This doesn't mean that some systems, not all, will need some kind of regular cleaning. This is the case for all properties in the UK, regardless of whether the walls are brick, stone or render. Thankfully, it's not overly difficult to either take preventative measures or clean the surface once it starts to look a little dirty.

If you have signs of algae growth, we'd recommend you be proactive and treating it with a good algae cleaner before it spreads. We have some available on our site here or here. These tend to incredibly easy to apply as they simply are sprayed through a normal garden low pressure spray. Algae is stubborn and can grow on almost anything given the right conditions, so it's better to nip it in the bud before it spreads. 

Light pressure washing can also be carried out, as long as care is taken not to apply too much pressure which may damage the surface. Industrial washers may be too powerful, but your average consumer grade washer that you buy from B&Q should be fine. Good quality non-acidic patio cleaners applied before washing down will also help with dirt removal. 

So what about exterior render paint?

We’re often asked whether applying exterior render paint is necessary to keep a property looking fresh.

With modern monocouche or through-coloured systems, the colour is built into the material itself. Unlike traditional sand and cement render, these systems do not rely on exterior masonry paint to achieve their finish. As a result, repainting should not form part of the normal maintenance cycle.

Exterior render paint is generally more relevant on older rendered properties where the original finish has faded or where a colour change is required. It’s a cosmetic solution rather than a structural one.

If you are looking to prevent dirt and algae build-up further, specialist breathable sealers can be applied. We will shortly be launching a new product we have developed called ProtxSeal which is incredibly easy to apply, again using a low pressure sprayer. Containing Siloxanes, ProtxSeal completely repels water and seals the render with a lotus leaf effect whilst still allowing the walls to breathe. Dirt and algae simply get washed away as it can no longer stick to the surface. This sealer is easy to apply through a normal garden spray, does not change the appearance of the render at all and can be used on ANY porous masonary surface.

We will also shortly be offering application services also for this product, please contact us for more details.

If you need any advice on how to keep your render looking fantastic for years to come do not hesitate to give us a call. 

It’s that time of year when we regularly get asked: “Do we scrape same day or next day?”

In all honesty, it’s a tough question, as all renders have slightly different setting times. Products such as K Rend, Parex render and other monocouche render systems can all behave differently depending on the weather, background, thickness and how early the material has gone on.

I understand the eagerness to move to same-day scrapes, but it’s not something that can be rushed. Trying to scrape back wet, sticky render with a render scarifier can pull the face of the material, throw off the colour and leave rough texturing issues that are difficult to put right.

As a general rule, if the air is dry and temperatures are predicted to stay in double figures from the minute you start until the end of the day, your render may be good to scratch the same day. That said, expect a late finish if temperatures are at the lower end of that scale. Get the pumps and trowel working early too.

Before scraping, always check the render has firmed up properly. A render scarifier should remove the surface evenly without dragging, smearing or clogging. If the material is still soft underneath, it’s usually better to leave it rather than risk damaging the finish.

The same applies whether you’re working with K Rend one coat render, Parex one coat render or another through-coloured monocouche system. Weather, suction and application timing will all affect when the surface is ready.

If you like more specific advice on the K Rend or Parex products we supply then please feel free to contact us.

I don't normally do reviews as applicators tend to like what they like but I felt the need to write a bit about the new K Rend Silicone K1 because I rarely get such good feedback from my customers from a product as I have over the past few months than I have with this one, so I decided to get onto site to see it for myself.

I've seen it running through Ritmo and G4 spray machines as well getting hand applied applied by some of the guys who were staunch users of the Silicone FT and I've got to say I was pretty much blown away! Anyone who's traditionally used silicone mineral renders will tell you that they aren't as easy to apply as the other standard renders on the market, including those from K Rend themselves and I'd have to agree. They are usually harder to mix, dusty and heavy under the trowel or straight edge with a tendancy to split if not mixed correctly.

That is no longer the case with the silicone K1! Through the pumps you honestly can't tell the difference from the standard K1 and those who hand apply will be pleased to know that you too can have a light, fluffy and easy to manipulate render as your machine hugging colleagues tend to hog!

K Rend K1 Silicone is a through-coloured monocouche render designed for external walls. As part of a silicone render system, it offers improved water resistance while still allowing the wall to breathe properly. That’s one of the reasons silicone rendering has become so popular on modern residential and commercial projects.

Compared to traditional sand and cement finishes, K Rend K1 Silicone provides a more consistent decorative finish with less ongoing maintenance. It’s commonly used as a coloured external render because the pigment runs through the material itself, helping reduce the need for painting afterwards.

Another benefit is its ability to cope with UK weather conditions. When applied correctly, it acts as a durable waterproof render for external walls while maintaining flexibility and appearance over time.

Like most silicone rendering products, timing and weather conditions still matter. Good preparation, correct basecoat application and proper scraping times will all affect the final finish. Getting the mix and suction right is just as important as the product itself.

Now, we have a render where customers can have the benefits of K Rends unique silicone enhancements and the applicators don't have to worry that they may be having a late night to get the job done. Everyone who has tried the new Silicone K1 has made the switch from the Silicone FT on the first try of the material! Check out our video below! Thanks to Russ Downing at Lord and Downing Render Systems for allowing me to spend time on site with the guys.

K Rend Silicone K1, 3 floors up flying through PFT G4 Spray machine. Cracking! @KRendRenders pic.twitter.com/05RYdrV2DQ

— Rendit (@RenditLtd) January 27, 2016

Verdict: 5 out of 5! 

Cracks in render are a common issue on both older and newer properties and can occur for a variety of reasons. In many cases, small hairline cracks are cosmetic and relatively easy to repair, but larger or recurring cracks may indicate movement, poor installation or underlying substrate problems.

External rendering systems are designed to protect buildings from the elements while improving the appearance of exterior walls. However, exposure to changing temperatures, moisture and structural movement can sometimes lead to cracking over time.

One of the most common causes of cracked render is movement within the building itself. As materials expand and contract with temperature changes, stress can build within the render surface, particularly if the correct reinforcement or expansion detailing has not been used.

Poor preparation during installation can also contribute to cracking. Issues such as insufficient basecoat thickness, incorrect curing times or applying render onto unstable surfaces can all affect the long-term performance of external rendering systems.

Hairline cracks can often be repaired using specialist fillers or flexible repair compounds before redecorating or recoating the affected area. Larger cracks may require removal of loose render, repairs to the underlying substrate and reapplication of the render system to ensure a long-lasting finish.

Modern silicone and polymeric external rendering systems are generally more flexible than traditional sand and cement render, helping to reduce the likelihood of cracking caused by movement or weather exposure.

In some situations, cracks may allow water ingress behind the render surface, which can lead to additional issues if left untreated. Addressing cracks early can help prevent further deterioration and maintain the appearance and performance of the render.

Preventative maintenance is also important. Regular inspections, keeping walls clean and ensuring gutters and drainage systems are functioning correctly can all help prolong the lifespan of external rendering and reduce the risk of future cracking.

If you are unsure whether cracks in render are cosmetic or indicate a more serious issue, it is always best to seek professional advice before carrying out repairs.

If you are unsure about repairing cracks in render, contact an expert today

Brick render is a popular exterior finish used to improve both the appearance and weather resistance of buildings. Commonly used in modern external wall rendering projects, render is applied directly onto brickwork to create a smooth, textured or decorative finish depending on the system used.

Modern rendering systems are available in a wide range of colours and finishes, making them suitable for both contemporary and traditional properties. In addition to improving appearance, external wall rendering can help protect brickwork from the elements and reduce long-term maintenance requirements.

There are several different types of brick render available, including monocouche render, silicone render systems and traditional sand and cement render. Each system offers different benefits depending on the property type, substrate and desired finish.

Monocouche render is one of the most popular options for external wall rendering due to its durability, low maintenance requirements and self-coloured finish. Silicone render systems are also widely used thanks to their water-repellent properties and flexibility, helping to reduce cracking and dirt build-up over time.

Traditional sand and cement render remains a common choice for some applications, although modern render systems often offer improved breathability, weather resistance and colour consistency.

Render can be applied to a wide range of surfaces, including brick, blockwork and concrete walls. Depending on the system being used, the process may involve a basecoat, reinforcement mesh and decorative topcoat to achieve the desired finish and performance.

External wall rendering is commonly used on:

• Residential homes
• Extensions
• Commercial buildings
• Garden walls
• Renovation projects
• New build developments

One of the key advantages of modern brick render systems is the variety of finishes available. From smooth contemporary appearances to textured or scraped finishes, render allows homeowners and developers to completely transform the appearance of a property.

When correctly installed and maintained, brick render can provide long-lasting protection against harsh weather conditions while significantly improving kerb appeal.

Whether you are renovating an older property or planning a new development, external wall rendering offers a durable and attractive solution for upgrading exterior walls.

Specially trained approved applicators are available for this product, depending on size of works required. Please contact us for further details.

Applying render provides an attractive and clean-looking exterior for commercial and residential properties. With a vast range of colours and finishes, there is a lot of choice when it comes to choosing a render system.

Before You Start

It goes without saying but you should ensure unopened packs of render are stored appropriately in a dry place to prevent damp from caking the render. Unprepared render also has a shelf-life, so make sure to check this before using it on a project.

Be confident that you know exactly what the render will look like when dry. If necessary, create a test panel.

When preparing to render a wall, it is also important to assess the type of surface you are working with. Rendering external stone walls, for example, may require additional preparation compared to blockwork or brick due to the uneven and porous nature of stone.

Rendering External Stone Walls

If you are rendering external stone walls, preparation is key. Stone surfaces are often irregular and may contain deep mortar joints or loose material that must be addressed before applying render.

Before starting:

• Remove any loose mortar, dust or debris

• Repair unstable areas of stonework

• Ensure the surface is clean and structurally sound

• Lightly dampen very porous stone to control suction

Because stone can retain moisture, it is important to ensure the wall is dry and suitable for rendering. On older properties in particular, choosing the correct render system is essential to allow the wall to perform properly once finished.

Taking extra care at this stage will help prevent cracking, poor adhesion or long-term performance issues when rendering stone substrates.

Getting Started

First, make sure you have all your tools ready and the render has been made up according to the instructions.

Most renders can be applied by hand or with a spray machine – make sure to check which type of application is suited to your render.

Apply the base coat to the required thickness and allow it to cure before applying any further coats.

Curing

Render needs time to cure, which is best achieved in warm, moist conditions. The initial curing process should be closely monitored over the first 2–3 days – the render should be kept from drying out, shielded from direct sunlight and protected against frost. Make sure to check the instructions on your render for any additional precautions or advice specific to your render.

Render needs time to cure effectively over a period of 3 weeks to achieve its final colour, and the render should be kept protected from inclement weather such as rain and high winds during the 24–48 hours immediately after application.

Extra care should be taken when applying render in cold conditions. It is not recommended to mix or use render if the temperature is below 5°C as cold temperatures slow the curing of the render and freezing temperatures halt the process entirely.

Finally, if you are in doubt about how to render a wall, do not hesitate to contact our experts who will be happy to help with any issues you may have.