What is render?
Render is used on external walls to seal them off to the elements, or to give a property a facelift. Early rendering was a messy business, slapped on the walls using sand and cement and finished with coloured paint. Over the years, render technology has evolved greatly, giving a much bigger choice of colours and finishes, and also enabling tailoring to specific environments.
For instance, hydrophobic renders can protect properties in damp environments from water penetration and weathering. Also, the renders contain flexible polymers, helping the surface retain its structure without cracking very easily.
Traditional render is subject to wear and tear and if not regularly maintained and repaired, can leave the building in a terrible condition. Cracks may appear on older render systems, which can then lead to damp and water penetration.
The thinner coat renders tend to use a lot fewer bags of material, which is why in most cases they tend to be much cheaper to install than thick coat renders.
What is K Rend?
‘K Rend‘ is often used in the external insulation business as a catch-all term for render. Just as the personal cassette player was most commonly known as the ‘Walkman’ throughout most of the 1980s and 1990s, K Rend has the similar brand recognition.
K Rend in fact is ‘only’ a brand with a large range of different renders, manufactured by Kilwaughter, the chemical manufacturer parent company in Northern Ireland. K Rend traditionally produced ‘thick coat’ renders such as dash receivers and monocouche and has recently also ventured into the family of silicone render products.
K Rend render is a water-repellent, breathable solution – low maintenance and available in most colours.
Despite its reputation, it is just one brand amongst a number of external rendering products in the market. You can actually get dozens of other systems sourced and installed that do a similar job.
What is the difference between K Rend and other render manufacturers?
As mentioned, K Rend traditionally manufactured traditional English thick coat renders, whilst in Europe thin coat flexible renders were a lot more popular. Over the years, various acrylic and silicone thin coat solutions have made it to these shores, and are now growing in popularity. A number of houses have been successfully retrofitted with these solutions.
Whilst K Rend also produces thin silicone renders, the European manufacturers probably have a longer history of using thinner coat products. However, K Rend stands up well against competitors’ products.
Both K Rend and other manufacturers now specify a flexible bead or mesh inserted into the base coat adhesive before the final layer of render is applied. However, since K Rend doesn’t have a full external wall insulation system, beading is optional where it is mandatory on many other render systems. It is our view that the more flexible the render layer, the longer its lifespan, as it will be less prone to movement and surface cracking.
Does K Rend offer an external wall insulation solution?
Whilst K Rend can be used as the render based system on top of insulation, the brand itself does not have a certificate for an external wall insulation system (ETICS). This is in contrast to many of the thin coat systems, which also come together with the external insulation system.
More and more, older homes are not just going through the re-rendering process, but homeowners are also upgrading the thermal efficiency of their properties as well as updating the render at the same time. It is a more cost effective way to re-render, as with external insulation the homeowner or occupier should look to realise heat cost savings over time that would go some way to pay for the cost of the job.
EWI Store take on K Rend and other render brands
We believe that certain renders will work in certain situations. For example, many properties in South Wales and Western Scotland are pebbledashed and the K Rend offers the perfect solution to repeat this process. Also, some architects may specify monocouche thick render scratch finish, and in these cases it is absolutely reasonable to want to go for the K Rend system.
If however, you are after a more robust and flexible system then silicone thin coat renders are the way to go, and it is wise to choose another manufacturer with a long history of this manufacturing process. This is why we think that thin coat systems like EWI Pro Insulation Systems, Johnstones and Sto work particularly well.