What are exterior wall coatings and what benefits do they offer?

The phrase “exterior wall coating” is to most people, fairly self explanatory.

It’s obviously a coating, for the exterior walls of a building, but is it really as simple as that?

This article explains in detail what a wall coating actually is by definiton, and the benefits of having one.

Exterior (external) wall coatings are also known as elastomeric (wall coatings), masonry coatings, textured coatings, liquid vinyl siding and of course, exterior wall “coverings.”

They are designed to replicate ordinairy house paint, but with advanced features not found in traditional paints.

Such features can include colour fastness, waterproofing, anti carbonation, anti damp, but a common feature to all is the fact that they are designed to outlast masonry paint many times over.

Why a coating and not paint, or is a wall coating actually a kind of paint anyway?

To explain in plain English, an exterior wall coating is a long life replacement for masonry paint, but with two main functions or features to it, whereas traditional masonry paint has only one feature: Decoration.

A typical external wall coating has the twin benefits of being both decorative, and protective, which stands the system apart from masonry paint in terms of lifespan and longevity.

Whilst painting the exterior walls of your house with masonry paint may well make it look nice, this feature will only last a couple of years at best before the paint starts to degrade.

The main benefit of having an exterior wall coating applied to your home is the fact that not only will it look aesthetically pleasing, as per paint, but it will carry on looking attractive, for at least 2 decades.

As with most exterior house painting, preparation is the key to a well executed paint job.

This means that any defects in the building walls, such as cracks or loose rendering, must be repaired before the application of an exterior wall coating.

Most reputable exterior wall coating companies offer a consumer warranty to uphold that fact.

The warranties offered vary in length, but normally the guarantee protects the end user against the coating flaking, fading, cracking or peeling.

Notable brands of exterior wall coatings available in the UK include Wethertex (wetherby stone), Andura, ProPerla, Plaspertex, Britannia paints and Renotex

Looking back to the late 1970’s and early 80’s, brands that emerged in the UK offering this as a home improvement service included BMS, Wallcote, Canadian paints and Kenitex.

Why resin based coatings far outperform water based masonry coatings

A major constituent part of most top brand masonry paint in stores and shops is WATER.

Therefore by definition, a purchase of a can of branded masonry paint for a house is a purchase of expensive coloured water.

Dulux weathershield paint is coloured water

The enhanced performance and longevity of the wall coating product is due to the fact that wall coatings are based on hard-wearing flexible resins to bind the various elements of the mix together. These resins are normally alkyd.

These elements can be perlite (marble in powdered form), binders, pigments or dyes, whereas masonry paint is water based, and therefore does not provide the type and level of weather protection or longevity that most homes require.

The experts at polymerdatabase.com say that ….

“Alkyd resins are thermoplastic polyester resins made by heating polyhydric alcohols* with polybasic acids or their anhydrides. They are used in making protective coatings with good weathering properties and are important ingredients in many synthetic paints due to their versatility and low cost.”

Therefore an exterior wall coating will last a lot longer than masonry paint due it’s chemical composition and makeup, but will carry out essentially the same function, and more besides.

Are all wall coatings sold as “trade only”?

Yes and no.

In general, an exterior wall coating is a special kind of enhanced paint product which has to be applied by trained installation teams.

DIY wall coatings are generally just paint with some form of added enhancement and should not be considered within the same level of quality and performance as trade wall coatings are.

In addition, a wall coating applied by a keen DIY’er will in no way meet the quality of application that a wall coating installed by a professional would, and neither will any warranty be offered

Applying a wall coating with no training or specialist knowledge may carry many hazards and risks that far outweigh any customer financial savings made.

A professional exterior wall coating application would normally include preparation works such as repairs to render or re-rendering, the removal of old paint and cleaning the walls, repairing cracks, replacing pebbledash or tyrolean, and masking up of doors, pipes and windows.

External wall coatings also have a very good opacity level compared to masonry paint.

“Opacity” is the term used to describe the “hiding power” of paints and coatings.

There are a number of things that affect opacity of a paint such as the colour of paint used, and the quality of the paint, along with the thickness of the product when applied.

Exterior wall coatings are made by various different paint manufacturers, and in several countries around the world.

Many of these products made overseas are specially formulated to meet the climatic conditions and ambient temperatures of that specific country.

Wall coatings are also adapted to the typical or most common form of construction of house in a specific country.

An example would be Wethertex MP44 masonry coatings which are best suited to the typical British or Irish house, which is traditionally constructed of brick, render or pebbledash.

For a balanced and unbiased opinion, Andura Classic 21 is another high quality exterior wall coating which benefits from these weatherproofing and highly decorative properties.

Both wall coating systems are British made, with a proven track record, and available from a variety of independent wall coating contractors around the UK.

The insulating qualities of a British external wall coating means that it can protect the outside of any typical house you would find in the United Kingdom or Ireland, from erosion, damp and general inclement weather, whilst also reducing wind chill, cold internal walls, and lowering heating bills.

This can be compared and contrasted with another high quality exterior wall coating product such as Tex-Cote CoolWall™, which is made in America.

CoolWall™ is designed to reflect the suns rays away from the walls of houses in hot American states, and therefore giving an added benefit of reducing home air conditioning expenses by cooling the property. Source:texcote.com/coolwall/

Other countries around the world have their own wall coating formulas which suit the needs of the houses in their own country.  A good example would be the highly insulated wall coatings found in especially cold countries around the globe.

Masonry paint will therefore only provide decoration for walls, whereas exterior wall surface coverings will provide extreme weather protection, in addition to decoration.

These wall finishes are tested in a laboratory with accelerated weathering machines, providing clear proof that a wall coating will last in excess of its 20 year sell-by-date, provided it has been applied correctly in the first place, and by a competent and experienced team.

Weather testing machine for exterior textured wall coatings

Further accreditation on many wall coating products are offered by the BBA, the British Board of Agrément. When selecting which brand to use, a wall coating that has been awarded a BBA certificate is preferable to one that has not been awarded a BBA certificate.

How does a wall coating differentiate itself technically from masonry paint?

A normal tin of emulsion paint (“Latex” in the USA), for example, can be opened and applied with a brush, by more or less anyone.

An external wall coating is a specialist product which requires training and special equipment to apply it, and therefore cannot be bought, or applied by, the general public.

A wall surface specialist coating is often much thicker than DIY paint in terms of volume and viscosity, and is therefore usually applied by a spray machine in the case of liquid resin based coatings.

They can also applied by a combination of a rendering trowel and a roller in the case of more viscous and/or cementious coatings (such as K-rend or Weber.)

There also exists a very clever exterior wall coating product (not offered by us) from France called Decopierre, which involves rendering a special mix onto a wall and then hand applying a pattern. The overall effect when complete is that of a stone built building, as you can see from this local council building in France below.

Decopierre on a council building in France
Decopierre on a council building in France

Due to the increased thickness of an exterior wall coating upon application, the system is very effective at covering scruffy, damaged, eroded, highly textured, or uneven wall surfaces.

A wall coating is designed to be a premium product for your home, rather than being a cheap or budget option such as masonry paint.

With this borne in mind, a long term view is the best approach to take when getting a quotation for a wall coating to be applied to your home.

A summary of the main benefits of an exterior wall coating, in the context of having one applied to your own home.

Having a company (such as Never paint Again UK) install a high performance wall coating to the exterior of your home, can bring many benefits and cost savings, both in the short term, and looking to the years head.

Front-of-harrogate-house-with-wethertex-exterior-wall-coating

Penetrating damp can be cured with an application of a wall coating

Wall coatings prevent damp and water ingress from entering the building due to the super hydrophobic water dispersants included in their manufacture.

This means a textured exterior wall covering, once applied in the correct manner to a damp building, will cause any moisture ensconced within the fabric of the building, to harmlessly evaporate, whilst preventing any further ingress of damp.

It is worth pointing out that masonry paint will NOT afford any damp protection at all.

Wall coatings are self cleaning products

A typical wall coating will rarely pick up dirt as masonry paint would do, but the nature of their water repellent features enable rainwater to wash away any dirt particles naturally and without concern.

Additional cleaning can be carried out manually if required, with a garden hose spray.

The ability to cover wall defects

An exterior wall coating is applied to a much greater thickness than masonry paint, often with the added elements of a texture within the coating.

This enables the wall coating to completely cover defects, previous repairs or cracks where masonry paint with a poor opacity, would not hide any pre existing wall problems.

Given the same thickness of applied paint film, not all paints are equally opaque (or transparent). We call this hiding strength or covering power.

The hiding strength (or opacity) of paint is largely influenced by the difference of the refractive indices of the pigment and the medium, particle size and dispersion of the pigment (i.e. particle shape and degree of aggregation of the particles), the proportion of pigment in the vehicle (i.e., pigment volume concentration or PVC) and the thickness of the applied film. These factors determine the opacity of a particular paint.

Source: George O’Hanlon, auithor of  “Natural Pigments”

Wall coatings also provide excellent resistance to the growth of mould or algae on walls

Green mould or algae growing on an exterior wall is often a problem in shaded areas of the house exterior, or in situations where the house is in close proximity to trees or extensive hedges.

Mould is an organic element and just like any other plant, it requires moisture to grow.

If mould is growing on an exterior wall surface, it often suggests that water is trapped near to the surface of the outside wall, creating a febrile environment for green mould to spread.

A typical exterior wall coating will not allow this moisture to exist in the wall, therefore dissuading and preventing the growth of green mould.

Adding value to your home: A gift that keeps on giving.

The application of an exterior wall coating to your own home will bring many benefits, and this importantly includes a good return on investment (ROI).

As a typical wall coating is designed to enhance your home, and give added features such as weather protection and the removal of the need to repaint, it can add significant value to any home.

“Buyers often look for homes that require few repairs, and no one wants a deal to fall apart because the home inspector [surveyor] found an issue the buyers can’t stomach. A little prevention can spare you from the pain of watching a buyer walk away.”
Source: Opendoor.com

This view is reinforced on the Australian property website localagentfinder.com.au who state that:

“One of the most cost-effective and easiest ways to spruce up your property is to give it a fresh coat of paint.”

Most exterior wall coating products are available in a variety of textures and colours, all designed to visually enhance a home, but with added benefits such as weather protection, never fade colours, and the ability to permanently cure penetrating damp and mildew.

Having an exterior wall coating applied to your home can bring significant benefits, whilst also not at all expensive to purchase the service. This has enabled thousands of smart homeowners across the UK to reap the financial benenfits of having this system applied to their homes.

This is despite its premium features and performance as a highly efficient and cost effective way of having the outside of your house painted.

Most homes can be repaired and painted with a wall coating in less than 5 days, and our own wall coatings come with a 20 year guarantee.

Thanks for reading our article today, if you could share this on social media we would be very grateful.

If you would like to find out more about a wall coating system for your property, call us free today, on 0800 970 4928 or complete our online application form

Scroll to top