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The use of timber cladding and elaborate wood detailing in new builds and refurbs seems to be on the increase in a big way. When wood is skillfully used in a contemporary design along with a great looking render such as those by K Rend or Parex the results can be stunning.

Unfortunately, in a lot of cases this stunning look may only be temporary as one key problem seems to be getting overlooked time and time again if the regular calls our Mendrend technical team receive are any indication.

A lot of the pressure treated timber on the market appears to be treated with a substance that is not completely water proof so when the timber gets wet the wood stain is then dragged down the wall which then pentetrates deep into any surface that is porous such as your normal cementitious render. The results can be devasting and extremely difficult to correct. We strongly advise if you are considering the use of treated wood in the design of you build that you check with your wood supplier that the treaments used in its production are completely stable in the presence of water or consider the use of an additional wood seal that makes the timber completely impervious to water.

Please call our technical team if you need any advice with the rectification of this issue.

We've specialised in repairing renders for many years now from the design and development to on-site application of our specially designed patented Mendrend range of products we have been focused on customer service as a core driver of our business.

During our time as render repair specialists prior to our focus on the supplying of materials we quickly realised that there is a key grey area when its comes to render applicators and the manufacturers warranties that are provided when renders are correctly applied. This grey area is building settlement; if a building settles (The vast majority don't but any building can.) and cracks after render is applied it tends to be the applicator who is blamed when in fact its absolutely no ones fault the issue has occurred. The applicator may then call the manufacturer in to see if the issue is covered under the warranty only to be correctly told that settlement is not covered under their standard warranty terms. This would be the case for pretty much any render system sold on the market today. 

This usually results in the applicator / builder / customer going round in circles trying to solve problem and one of them ends up having to pay to correct the issue depending on who loses the argument! 

Our no quibble crack free guarantee provided when we supply render systems is designed to solve this age old problem. We have teams of technicians who operate nationwide assisting customers and resolving disputes daily. I'll be frank we don't aim to be the absolute cheapest render supplier out there, I'll leave that to the guys who cannot provide their customers with assistance or have no idea what they are selling.  We aim to provide low competitive prices whilst providing help when needed.

We invite all our applicators to offer this guarantee to their customers and maybe offer a cheaper price without this guarantee if a cheaper supplier is available and let the customer themselves decide.

We invite all our customers looking to have their own properties rendered to strongly consider our industry leading backup service for what tends to be a small addition to the price of having the works done.

Those who have ended up actually needing repairs done have found our service to be invaluable. A simple crack which normally could have been a problem to fix suddenly becomes a simple phonecall. This service is currently implemented on large housebuilder sites such as Taylor Wimpey, Arncliffe Homes and Cyden Homes with great success.

If you have any questions about how you can provide your customers with better service please contact us.  

It's started.

The phone has rang a couple of times this week with customers a little flabbergasted that the thin coat render they applied a few days ago has washed off in the last rain shower with a slightly accusatory tone in their voice.

All I will say on this matter is that there is nothing wrong with the material when this happens, and its not unusual for customers to start flagging this issue up at this time of the year, as its the same every year. The simple fact is that some thin coat renders perform better in cold and damp conditions than others and each job needs planning accordingly.

Traditional thin coat resin based bucket renders generally depend on good air drying conditions as there's no curing process with these. If the air is constantly cold and damp they struggle to dry if not protected and can hang around for days only for a rain shower then take them off the wall in a hair curlingly frustrating fashion. They will dry in cold (5c+) air if the air is dry and crisp and the background is dry, but it may still need a good 24 hours before it is considered safe from the weather. Be careful with these at this time of year, a weather shielded scaffold and a space heater goes a long way to alleviating some of the problems cold damp weather may bring with these types of renders. 

Silicone thin coat render systems can be particularly sensitive to cold and damp conditions during application. Low temperatures and excess moisture may affect curing times, adhesion and final finish quality if the material is applied outside manufacturer recommendations.

The new mineral thin coat renders such as K Rend Mineral TC perform better in colder conditions with less risk of washing off because they cure and are much less dependent on good air drying conditions to harden. They still need to be applied on a dry background, but a bit of fog or moisture in the air won't prevent them from going off completely and drying times will be measured in hours rather than days. Temperatures still need to be a minimum of 5c on a rising thermometer. This is an excellent winter alternative to a traditional thin coat render if you have a job that needs to be done!

If you have any questions or need advice, please contact us!

We have briefly mentioned in previous blog articles some of the benefits and reasons you might want use an external render system, but it is worth further elaborating on these points and more as to why rendering an external wall is beneficial to a property.

Improve the external appearance of a property

There’s no denying that applying a render system to an old, tired-looking building will transform its appearance – making it look modern and more visually appealing.  Local authorities will often use render when renovating their properties for this reason.

This aesthetic improvement can be beneficial in multiple ways – if you live in the property - it makes your home look nice. If you looking at selling a property, it can make it look more visually appealing to potential buyers. 

From a wide range of colours, to a huge selection of textures and finishes, there are a wealth of possibilities available when rendering a house.

Increase the thermal efficiency of walls

Some renders – like the K Rend Silicone Thin Coat range – can be used as part of an External Wall Insulation System. While most render systems themselves are not classed as insulating (though they do provide a small amount of innate insulation), when used as part of an EWI system they can help increase the thermal efficiency of walls and reduce heating bills – not to mention the other benefits featured in this article.

Weatherproofing

External walls that are in a poor condition can lead to the ingress of water and external debris which will worsen if left untreated. The use of a render system on an external wall forming a barrier, protecting a building from the elements. These renders incorporate water repellent technology, protecting against water whilst still allowing the substrate to breathe.

One of the biggest advantages of coloured external render is that it improves the appearance of a property while also helping protect the external walls from the weather. Modern coloured render systems are available in a wide range of textures and finishes, giving both homeowners and developers far more choice than traditional painted surfaces.

Many modern silicone render systems also offer improved flexibility and water resistance, helping reduce maintenance and keeping the finish looking cleaner for longer.

If you need help with applying render or you would like to know more about the benefits of render, contact our experts today.

Textured exterior wall paint and textured render offer different ways to finish an external wall. Textured paint adds a decorative texture through the paint coating, while render creates its finish through the material’s grain size and how it is applied and worked.

The right choice depends on the existing surface and the finish you want to achieve. Painting an already textured wall is also different from using paint that creates texture. This guide explains those distinctions and explores the render finishes available from Rendit.

What’s the difference between textured paint and render?

Textured exterior wall paint creates a textured coating on a suitable surface. The effect varies by product, so check the manufacturer’s description and application guidance for the finish you want.

Render forms a separate layer on the wall. Its texture depends on the product and finishing technique. For example, Parex Monorex can produce different render finishes, including scraped and spray-textured effects.

If your wall already has the texture you want and simply needs its colour refreshing, a compatible exterior render paint may be suitable. Check the existing render, previous coatings and preparation requirements before choosing a paint.

What types of render texture finishes are possible?

Each manufacturer has renders with different finishes, and the look you wish to achieve will influence the render system used.

Textured, Smooth, Scraped and even more unique finishes such as brick effects or ashlar detailing are achieved via a combination of the application method and the finishing tool used.

How are different texture finishes achieved?

Standard renders usually have 3 categories of finishes - scraped, smoothed and textured – each with their own subtle variances. For example, Parex Monorex can be scraped to achieve a fine or medium finish. 

Scraped texture finishes are achieved by scraping the render with a scraping tool before the render has set hard whereas using a trowel or float will result in a smooth-looking finish.

Applying the render using a spray machine will give a far more pronounced texture finish, similar to tyrolean and roughcast.

There are also more technical and specialist finishes such as pebble dash where an aggregate is thrown onto a wet receiver; and brick or ashlar effects, where a pattern is cut into wet render to give it the appearance of real brickwork. 

Choosing a finish for your exterior wall

Start by deciding whether you want to refresh the colour of an existing textured surface or create a new texture. For repainting, choose a paint compatible with the existing render and any previous coatings. For a new render finish, select the render system and application method together.

Before ordering, check the manufacturer’s guidance on suitable surfaces, preparation and application. For help choosing from Rendit’s render and paint ranges, contact our technical team on 01302 884385.

One thing I’ve learned over the years is that most rendering problems don’t usually come from the material itself. More often than not, they come from poor preparation, rushing the job or ignoring manufacturer guidelines.

Every render product is designed to work a certain way, and that includes everything from water ratios and application thickness to scraping times and weather conditions. Trying to cut corners or “do it your own way” can quickly lead to cracking, poor finish quality, colour inconsistency and unhappy customers.

This is especially true with monocouche render systems.

Modern monocouche render products are designed to provide a durable, through-coloured finish, but they still rely on correct application methods to perform properly long term. Even experienced renderers can run into problems if the conditions aren’t right or the guidance isn’t followed closely enough.

One of the biggest mistakes is assuming every wall will behave the same. Suction levels, background condition, temperature, wind and direct sunlight can all affect how render cures and firms up on the wall. A setup that worked perfectly one week can behave completely differently the next.

Water content is another major factor. Adding too much water might make the material feel easier to work with initially, but it can weaken the finish, affect colour consistency and increase the risk of shrinkage or cracking later on.

Timing is just as important.

With monocouche render systems, ruling off and scraping too early or too late can completely change the final appearance. Scraping before the material is ready can drag the surface and expose inconsistencies underneath, while leaving it too long can make the render difficult to work and affect the texture across the elevation.

Weather conditions also need to be taken seriously. Applying render during freezing temperatures, heavy rain or strong direct sunlight can create all sorts of avoidable problems. Even high-quality materials can struggle if they’re being applied outside the recommended conditions.

The same applies when using spray on render equipment. Machine application can massively improve speed and consistency, but only when the setup, mix and timing are all correct. Spraying material onto a poorly prepared background or in unsuitable conditions will still lead to problems no matter how quickly the wall goes on.

Preparation matters just as much as application too. Correct use of primers, beads and render base coat materials helps create a more stable system and improves the overall finish quality.

At the end of the day, manufacturer guidelines are there for a reason. They’re based on testing, experience and understanding how the system is designed to perform. Ignoring them might save time in the short term, but it often creates bigger issues further down the line.

A good renderer doesn’t just know how to get material on the wall. They know how to read conditions, prepare properly and work with the system rather than against it.

Use an Expert for Expert Results

Our qualified technicians are experts in applying K Rend and can help rectify any mistakes or issues that occurred during a previous poor application. Contact us today for help and advice on k rend application.

As we have written about before, large cracks in render can be an indication of a major problem in the substrate. However, smaller and much less serious fissures can also appear. These fissures tend to be a lot smaller than cracks (around 0.1-3mm in width) 

Origins of fissures in render

Like cracks, fissures can occur due to movement from the building or the substrate the render has been applied to. Whereas large cracks tend to be an indication of a more severe issue, minor fissures usually occur due to minor inconsequential movement in the substrate.

What to do if you find fissures in render

It goes without saying, but you should always seek the advice of a professional before attempting any repairs. Determining the origin of the fissure is essential to ensure that there are no recurring instances of the problem. It is also advisable to wait for a period of at least 6 months to make sure that all fissures in the render system have stabilised.

Repairing fissures in render

Our patented Mendrend Flexible Fissure repair system is specifically designed to repair fissures in render from leading manufacturers and is supplied in a range of colours intended to match render manufacturer colour ranges. We also provide a comprehensive support service for this product. 

Rendit offers expert help and advice on repairing fissures in render – contact us today to find out more

One thing some applicators are better at than others is providing their customers with sample test panels of a finished render product as it can cause big problems with customers who are expecting their render to look exactly like it does in the brochure or even worse on their computer monitors!

The two render samples shown in the above picture are made from exactly the same render from the same bag. The sample on the right was simply scraped much earlier during the drying process than the render sample on the left and the difference that can make on the outcome of the final colour of all cementitious renders can be quite profound. It is for this reason we strongly recommend that you complete customer samples so you can test and verify the colour with them before ordering any materials 

It is very common for applicators to scrape renders early, therefore the colours achieved on site could possibly be much stronger than the colours of manufacturer provided samples which are made in a laboratory under ideal circumstances. It should be noted that all manufacturers of cementitious render products would deem this to be normal behaviour of the product.

We are happy to provide assistance with this, please feel free to contact us!

Modern waterproof render systems are designed to cope with the changing weather conditions we regularly experience in the UK, but correct application is still essential. Even high-performance silicone render systems and monocouche renders can suffer from issues if they are applied during heavy rain, freezing temperatures or excessive heat.

Most waterproof render systems need stable drying conditions to cure correctly. If fresh render is exposed to rain too early, it can lead to streaking, patchiness or weakened surface strength. On hot days, rapid drying can increase the risk of cracking and inconsistent texture.

When carrying out silicone rendering for external walls, it’s important to follow manufacturer guidance carefully and protect freshly rendered elevations where needed.

Know your conditions

It goes without saying that before you begin the application process of any render, you should read and fully understand the application instructions supplied by the manufacturer.

The type of render system being applied is another factor to consider. Dry dash systems are more resilient to wet and cold weather than their silicone counterparts.

It is also advisable to check the weather forecast for your planned application dates – try to avoid any days with excessive rain, wind, heat or cold. Extreme weather conditions can severely affect the both the application and drying / curing times of the render. 

Simple Solutions

In hot weather, do not apply render on walls which are exposed to direct sunlight. Instead, start on an adjacent wall in the shade and follow the sun around the building. This method allows you to work in sunny weather, whilst avoiding any curing issues direct sunshine may cause.

Certain weather conditions will slow the curing process down – usually due to colder temperatures (less than 5oC) or high humidity (90% and higher). If this is the case, then the render will retain moisture for a longer period of time and if sustained will become more susceptible to damage from trapped moisture so it is essential that the render system is protected during this stage.

Ask an expert 

At Rendit, we offer a 2-year crack free guarantee on our Render Systems, so if you need any help applying your render contact Rendit today!

It’s one of those debates that always gets people talking on site.

Do we really need to two pass with K Rend and Parex, or are we just making more work for ourselves?

The honest answer is that there’s no single rule for every wall, every day or every product. A lot depends on the background, suction, weather conditions and how the material is behaving once it’s on the wall.

With systems such as K Rend one coat render and Parex one coat render, the term “one coat” can sometimes be misleading. Yes, these products are designed to achieve a through-coloured finish without traditional sand and cement backing coats, but that doesn’t always mean a single-pass application is the best option in every situation.

Some renderers are happy to apply monocouche render in one pass all day long, especially on consistent blockwork with manageable suction. Others prefer a two-pass application to help control thickness, improve consistency and reduce the risk of cracking or hollowness later on.

Personally, I think it comes down to reading the wall properly.

If the background is pulling hard or conditions are drying the render too quickly, splitting the application into two passes can sometimes give you a much cleaner and more reliable finish. On the other hand, if conditions are right and the material is sitting nicely, there are jobs where a single-pass application works perfectly well.

A lot of this also depends on experience. Some applicators know exactly how far they can push a wall, while others would rather play it safe and build the material up gradually.

The weather also plays a massive part. Warm temperatures, wind exposure and direct sunlight can all affect how quickly monocouche render starts to firm up. Trying to rush larger areas in difficult conditions usually causes more problems than it solves.

Whether you’re using hand application or spray on render methods, timing is everything. Getting enough material on the wall while still being able to rule and scrape it correctly matters far more than trying to save a bit of time.

There’s also the question of finish quality. Two-pass application can sometimes help create a more even appearance across larger elevations, especially when working with lighter colours or areas with inconsistent suction.

At the end of the day, most experienced renderers already know there’s no magic answer. Some jobs suit single-pass work. Some don’t. The important thing is understanding the wall in front of you rather than blindly following what somebody else says online.

K Rend and Parex are both solid systems when they’re applied correctly. Whether that ends up being one pass or two often comes down to site conditions, experience and personal preference more than anything else.

 If you would like more specific advice on the K Rend or Parex products we supply please contact us.