painting interiors

What wall surfaces are not suitable for exterior textured coatings?

Exterior wall coatings are the best way to make the exterior walls of your house maintenance free but application guidelines must be adhered to, for maximum longevity.

In this article, we turn our normal approach on it’s head and explain that although our exterior wall coating system works wonders on most houses, there are one or two examples where they should NOT be used and therefore we also suggest what you SHOULD use instead of coatings.

To start with, and especially if you have surfed in directly to this page and wondering what the hell this guy is going on about (!), let’s briefly explain what we mean by exterior wall coatings.

  • This informative article will only take 3 mins of  your time (I promise!). Thank you

What is an exterior wall coating?

An exterior wall coating is a very durable paint finish that can be applied by experts to most homes and buildings, but if the wall surfaces is not prepared or is not suitable, the expected lifespan of the coating will be only a fraction of the intended duration, in our case 20 years.

Why do we have these guidelines about applying exterior wall coatings?

Because like many home improvement sectors, as having an exterior wall coating became popular, there were many companies (now thankfully gone) that would consider applying an exterior wall coating to almost anything, as long as someone was paying them to do it.

Cue a line of unhappy customers, shabby looking wall coating jobs and bad press from people who have been “scammed” by a wall coating company not sticking to the rules.

Its not just our industry, but other home improvement sectors too such as double glazing, driveways and so on.

Many companies such as ours, and the wall coating companies that we deal with, offer a 20 year warranty again cracking, flaking, fading, chipping and peeling, but only if they are done right, to the correct surface. If not, they wont last and any guarantee with be worthless.

As NEVER PAINT AGAIN and other similar professional Wall coatings companies have survived over the years by doing things in the CORRECT WAY, we have collated a short list of surfaces and occasions where, in our own professional opinion, a spray applied exterior wall coating should NOT be applied.

The following is based on REAL experience.

What surfaces would NOT be suitable for a spray-applied wall coating?


A texture coating installer should NOT:

  • Skimp on preparation or ignore repairs such as cracks.
  • not lay dustsheets down or do proper window masking making an unholy mess.
  • be rude or aggressive to customers, nor swindle (con) them.
  • Turn up for work in “tramps” clothes and in an old estate car.
  • Enter a customers house without explicit permission, nor use the “facilities” and hospitality of the persons home without their knowledge.
  • Paint over loose and hollow render.
  • Fill cracks with un-thinned coating material to “save time” instead of cutting the cracks out and filling with an epoxy resin mortar.
  • Do NOT apply coating over flaky and loose paint, or moss and green mould.
  • Do not write a quote on the back of a cigarette packet. Use proper paperwork and invoices.
  • Do not leave out the primer. If primer is not used, the wall coating may fail.

Surfaces and building types that are unsuitable for a resin based wall coating.

  • Very old cob houses. (also called Adobe or rammed earth) are suitable in some cases but not all, and a full survey is always recommended by someone familiar with painting older houses, as to ascertain its suitability for acceptance of an exterior wall coating.


  • This refers mainly to the very old houses from several hundred years ago that we have seen in Devon, and especially listed buildings. Our coatings are very breathable so it is unlikely to cause any issues, but as we honour warranties, a full inspection is needed. Lime render or lime wash is a suitable covering for this type of house. If your surveyor say it is suitable for a coating then it is.


  • UPVC surfaces including pipes and cladding. Special paints are available for the job.


  • Wooden areas. (wood expands and contracts massively and the coating will fail if applied to wood. ***USA Vinyl siding companies pls take note. Your coatings on wooden siding will NOT last and will make you look like an amateur). It is best to use a good exterior wood paint. UPDATED 2015: The only way to apply a wall coating to a wooden wall surface is to mesh it with EML and render over it, like we did here.


  • Glass, marble, tiles or other glazed surfaces. Once again there are special paints for this, but if you are wanting to paint over glass, WHY?! Replace the glass with a hard surface if the window element is no longer needed.


  • Surfaces under water. Our coatings will NOT do the job (!), however there does exist a special underwater epoxy coating, made by Hempel.


  • Walls with no damp course such as garden walls. We CAN apply a coating to this but it would not be covered under our warranty. It is often best to paint yearly with a good quality masonry paint, don’t waste your money on anything else.


  • Floors or other traffic or “contact” areas. There are special floor paints and coatings that will do the job very well. It highlights the point that there are many different types of coating for different uses, so always pick the most suitable products for the job.


  • Metal garage doors or vehicles! Once again, use metal paints and not paint or wall coatings that are designer for homes!

So what surfaces ARE suitable for a wall coating?

Rear of Bristol house ready to apply exterior wall coating

Most exterior walls made of  Stone, brick, rough cast, harling, render, asbestos sheeting, pebbledash, mock tudor panels, and spar dash are suitable, however if you are unsure, please do get in contact with us, we are always happy to help.

You can call us FREE for advice at any time on (0800) 970 4928

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