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Rendering On Painted Exterior Walls: The Essential Guide

rendering-on-painted-exterior-walls

Improving the look of the exterior of your home with render will both improve its value, and protect the brick underneath – but is it a good idea to render your home if it has already been painted?

Your painted walls may already have enough protection (if you have used the right products), but also, the render may not stick correctly, and the result could be a disaster.

Here, we talk about the benefits and disadvantages of render, why preparing the walls is highly important, and, ultimately, whether it’s preferable to opt for a painted finish instead?

Rendering On Painted Exterior Walls: The Basics

You may have decided to paint the outside of your home just to improve how it looks in the short term. Using standard masonry paint will make your brickwork look fresh and clean, but over time, the paint may have started to flake, or take on a ghastly, grimy appearance.

This is the point at which you wonder if rendering over it might be a better long term solution, rather than painting it once again, and starting the process over ad infinitum.

Unfortunately, rendering over painted brick is not a simple solution to your problems, and could actually result in complications further down the line.

rendering-on-painted-exterior-walls

If your walls are starting to crumble, show signs of cracks, or are letting water penetrate through the brickwork, the idea of rendering over them can be a particularly popular proposition. However, it is worth noting that you are literally painting over the cracks

What Is Render And How Much Does It Cost On Average?

Render is usually made from a mixture of sand and cement, although these days, it may be made more flexible by adding resin products to the mix before application. It may also be coloured, so that it doesn’t need to be painted once it has been applied.

It is added to your prepared walls with a trowel in layers of thin coats, with the final coat being slightly thinner, to achieve a smooth and streamlined appearance. In some cases, the render is left textured, or is even prepped and pebbledashed, to create a charmingly rustic look.

It is estimated that a render job on a three bedroom semi will cost around £2500, and will take around one week to complete – although the render will need several weeks to dry completely.

Additional costs may include scaffolding and two coats of masonry paint, to protect the render from the onslaught of the elements. If old render needs to be removed, the costs and the time involved will increase by as much as 100%.

2 Main Reasons To Render Your Exterior Walls

There are two main reasons why people choose to render their exterior walls: to improve the look of the home, and to protect walls that may be damaged, and detract from the property’s frontage.

If you are looking to improve how your home looks, render can be an excellent option, but it is down to personal taste. Many people love the way that natural brick looks, and they may not like it if their home looks different the neighbours.

Also, render effects, such as pebble dash and textured coatings, are of their time, and what looks good now may not be acceptable or fashionable in ten years time.

If your walls are starting to crumble, show signs of cracks, or are letting water penetrate through the brickwork, the idea of rendering over them can be a particularly popular proposition. However, it is worth noting that you are literally painting over the cracks.

Repairing the walls before doing any work is important, and will ensure the render lasts longer. However, although render that is applied carefully and professionally will stop water getting into your walls,  there are other solutions available that are well worth considering.

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Rendering Over Already Painted Walls: How To Do It

Rendering is already an expensive home improvement job, however, if your exterior brickwork has already been painted, the costs of rendering will increase once again.

This is because the surface that the render is being applied to may be too smooth and shiny for the mix to adhere to correctly. Without the right type of preparation, the render may simply slide off over time.

It is recommended that painted homes are prepped for installation using a process called “meshing” before the render itself is applied. This involves drilling into the brick, and fixing thin mesh sheets over the entire wall. This provides a rough surface for the render to adhere to.

This will also mean that more layers of render may be required to cover the mesh adequately, and to achieve the desired results. Clearly this process will add significantly to the cost of the job, and may result in a poor quality finish.

Another method involves using a first coat of adhesive, and embedding a fibreglass mesh directly into the coat. Once dry, fixings are used to ensure it stays put; this creates a surface that is rough enough to accept the render, although the adhesive must be chosen for the purpose of sticking to smooth painted walls.

Some professionals do suggest that preparing the walls to obtain enough grip may be suitable. This involves removing as much of the paint as possible with a pressure washer, and then using a hand grinder to “key” the walls over as much of the surface as possible.

The remaining paint needs to be flake free, and there needs to be enough exposed brick for the render to stick properly. Once again, this is an involved job that can add days to the project, and demands the expertise and input of professional contractors.

rendering-on-painted-exterior-walls

By deciding to simply paint over the existing walls with a hydrophobic and long lasting house paint, you are getting the best of both worlds – a home that looks great, and a finish that you can trust to do its job, and go the distance in terms of long-term property protection

Are There Any Alternatives To Rendering?

If the prospect of rendering is giving you concern, you might want to consider repainting your walls with a more suitable exterior paint that will give you the protection and good looks you want, but at a cheaper price, and without long-term complications.

Hydrophobic paints are a new concept that prove perfect for exterior brick walls, and offer as much as 20 years of protection from water and damp. These products come in coloured versions to enable you to attain the fresh clean look that you want.

Or, if you like the natural look of the brick on your home, you can choose a clear version that cannot be seen. Either way, they both offer the following benefits over rendering:

● They provide a waterproof coating to the brickwork, protecting your home from damp.
● They offer an additional coating of insulation that will keep your home warmer, and lower your energy costs.
● They last for an impressive 15 to 20 years before they need to be reapplied, and in many cases, the longevity is much better than this.
● They can be applied over existing paint – however, the walls will need to be carefully washed, and the old paint sanded down if it is flaky, or unable to bond to the walls correctly.
● They are designed to allow the walls to breathe, even after application. The paint prevents moisture from penetrating through the brickwork, but does allow existing moisture to dry out – preventing issues with damp building up inside your walls.
● The finish comes in a number of colours and attractive finishes that can help you to set your home apart from others on the street.
● Painting your home can be achieved for less than £1000 – a fraction of the cost of rendering an existing painted home.

You may have painted your home exterior with the very best of intentions, but as that painted finish starts to deteriorate, issues will inevitably arise over time.

By deciding to simply paint over the existing walls with a hydrophobic and long lasting house paint, you are getting the best of both worlds – a home that looks great, and a finish that you can trust to do its job, and go the distance in terms of long-term property protection.

Protect your property for the long-term, with the help of exterior wall paint. Take the first step to achieving moisture-free masonry today, by calling 0800 1700 636, or, alternatively, by simply clicking the button below!