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How to Render a Wall: All You Need To Know

external wall insulation details how to render a wall

Rendering is a job similar to plastering. It is a job that requires plenty of practice, and a high degree of skill. As with many similar jobs, it is not advisable to do it on your own. People often ask how to render a wall, thinking they will do it themselves.

The process is very similar to plastering for internal walls. Rendering is pretty much the same job, just done on the external walls.

The role of rendering is to protect the covering structures of the building against impacts of the external environment. But if you want to know how to render a wall, you must educate yourself.

There are many other alternatives that are much better than rendering. Now, while you can try and save some money by doing the rendering yourself, we always recommend hiring a professional. But before we get there, let’s talk about the disadvantages of render…

Disadvantages of Render

There are two main types of rendering materials: sand and cement. Both come with their own set of problems, but generally speaking, sand and cement rendering both possess a number of flaws.

The first problem is structural. Sand, and cement in particular, is inflexible as a material, which means it is prone to cracking. When sand and cement are put under the pressure of performing under extreme types of weather, they crack.

The render cannot handle extremes of cold and heat The temperature changes will cause the render to expand and contract. The result of this phenomenon is the appearance of cracks on your walls.

These cracks will allow for water to get into the walls and your internal walls will suffer. The older your render is, the higher the chances of cracking. The end result is that due to cracks and moisture in the inside, you’ll notice big patches of moisture forming on your internal walls.

The second disadvantage is closely related to the first one. Because render cannot handle extreme temperatures, you will notice fallen parts of render. And they do not look good.

The problem is, you cannot just fill those cracks and holes with render. You have to re-render the entire house. That means that maintenance of render is expensive.

Render reduces the ability of the building to get rid of an excess build up of moisture. Note: this applies only for buildings without a cavity wall. If you have a cavity wall, the problem can be solved easily.

However, if you do not have a cavity wall, the render will vastly reduce the ability of your building to circulate the moisture effectively.

Last, but not least, let’s talk about the decorative aspect. Because of all the problems stated above, yellow water stains will appear on the render. These water stains across the façade look unattractive, decreasing the overall appeal of your property’s exterior.

how to render a wall

Alternatives to Rendering

Consider the following scenario: You live in a house whose external walls have a lot of “blown bricks”. You know it will take a lot of time to replace them. And you wonder: should you learn how to render a wall.

Now, while you think of rendering, let’s examine other options. The wall is probably damp, and you need to think of a solution that will solve the damp problems. You just noticed a new damp patch.

The best solution is installing wall insulation. Before you run to the store, think of this. Wall insulation is a sensitive topic, and it requires skill, machinery, and expertise. If done improperly, and you haven’t sealed the house as needed, you will get moisture and damp problems despite the insulation.

Wall coatings come in different textures, finishes, and colours. They protect your house from flaking, blistering, and tearing, all while concealing cracks and gaps. Here are the advantages of wall insulation as an alternative to rendering:

– Reduced heat loss through the walls

Reduced energy bills between 10 and 50%

– Protects your home from penetrating damp

– Protects your home from penetration of chlorides, contaminating agents, and damaging salts

– Provide your home a completely breathable weatherproofing solution

– Increase your EPC rating, and the value of your property

Why Wall Insulation?

Wall insulation not only takes care of your rendering problem, but does much more for your home as well. Wall insulation is a product designed for insulating bricks and other porous building materials.

How does it work? We are glad you asked. The product works by chemically bonding to the surface. Once the product bonds to the surface, it penetrates up to 17mm deep. At this point, the product creates an invisible insulation barrier.

Our product is based on the latest nanotechnology that can bond with bricks, but also to concrete as well. Wall insulation offers protection against rain, dirt, algae, pollution, oil, and anything else the harsh British weather can throw at your house.

The most important part is that you will solve the rendering problem, and your property will get adequate protection from moisture. Our product reduces water absorption by more than 95%, resulting in no damp or condensation whatsoever.

Another benefit is maintenance. We talked about one of the disadvantages of rendering is that you need constant and expensive maintenance. Well, with wall insulation, that problem is gone.

The product has a lifespan of 20+ years. And it is self-cleaning. Because of the way the product bonds to the surface, it does not allow dirt particles to hold onto the brickwork. In other words, dirt particles flow off with rainfall.

The insulation will also transform your home into a breathing masonry, that has much better thermal conductivity and insulation properties.

If you still think about how to render a wall, let’s look at another test. Rendered walls allows moisture, and just 5% damp will reduce the thermal efficiency of your home by 50%. Just think how high those electricity and energy bills will be.

External Wall Insulation Installers and how to render a wall

Heat Loss Map – Before and After External Facade Coating Application

Why Is It Better Than Rendering?

First off, wall insulation is also some type of rendering. Why? Because the installation process itself includes rendering. Here is how it all goes down.

Once you decide that you want wall insulation, and you contact our professional team, and we will inspect the outside of your outside walls. The goal of the inspection is to identify any problem that might happen.

The process continues with power washing, another step taken to identify problems. Power washing will remove years of accumulated dirt, mould, and loosely adhered paint on the outside walls.

Any other foreign substrates will be removed as well. The process will clearly define and highlight any areas that need repair work. The “cleaning” part of the process also includes algae treatment. That means if there is any moss or algae on your walls, the area will be treated with fungicidal agents.

It is now time for the repair part of the process. This is the part where rendering will be done. First, the team will repair all cracks on your home, by filling them with quality filler.

Any blown and/or damaged render is removed, and then the surface is re-rendered to match the existing surface. Surfaces of poor quality are subject to bagging, or an additional stabilising procedure.

Our team will apply SBR/Unibond Bag Coat to the surface to add more adhesive qualities and additional stabilisation. Doors, windows, gutters, and drainpipes will be masked with tape.

Next up, it’s time for the coating process. The first, or primer coat, is a specialist coating, applied to the surface to ensure there is an excellent bond between the surface and the substrate.

During the coating application, the team will apply a long life protective wall coating. Thanks to industrial machinery, this process is fast and efficient. 

After the project’s completed, the team will thoroughly clean the jobsite. You will be asked to inspect the finished work. If you have any complaints, the professional contractors will address your concerns with immediate effect.

Ready to prep your exterior walls to perfection? Talk to our team today by calling 0800 1700 636!