Roughcast render repair: 【How to】 Repair Roughcast Render

Pebbledash Repair –

by Pete Thomas

Pebbledash or Roughcast?

Both processes usually involve gravel or shingle rather than whole pebbles such as you might find on the beach. It’s easier to just say stones, but it can be pea shingle or gravel, often including small or broken sea shells.


This is where the stones are thrown (cast) at fresh render so they stick to it.


This is a similar process, but the stones are mixed with mortar before being cast. This results in a textured  mortar finish rather than the stones actually showing over the render.

Either can be overpainted (and we see both examples in the Triangle) however roughcast is easier to paint as it starts off as a smoother finish, depending on whether the stones are smooth or broken with sharp edges. When you paint over pebbledash several more coats may be required before all air pockets can be eliminated and a smoother appearance achieved. Some decorators may prefer to spray, especially if large areas are involved.

As you can see from the article below, when repairing or patching up pebbledash it can be very tricky to get a consistent match with the existing, due to matching render colour, pebble colour and size, and taking weathering into account. It may be far easier to overpaint, however you will need planning permission to paint over bare pebbledash.

Conservation & Repair of Pebbledash

From an article by Jonathan Taylor originally published in The Building Conservation Directory 2009. A full version of the article is available at’

The repair of Edwardian pebbledash and roughcast is still a relatively new area for conservators. The standard solution to cracks and coat separation (either the outer coat or the base coat from the substrate) is to hack back to sound material, leaving edges slightly undercut where possible to improve the key. Tapping with a wooden implement such as the handle of a chisel will help to identify sound areas. Brickwork joints are then raked back to provide a key for the new mortar which is applied in two coats to match the existing.

At Port Sunlight, conservation officers at Wirral Council recommend that, for a moderately strong and porous background, a typical mix for dubbing out and the undercoats would be Portland cement, lime (hydrated high calcium lime) and sand, in the proportions 1:1:6 by volume. The mix for finishing coats would be cement, lime and well graded sand (to BS 1199), in the proportions 1:2:9 by volume.

Weather is not the only enemy!

For the pebbledash, stone which has been selected to match the original in size, colour and type, should be dashed on evenly using a scoop while the topcoat is still soft and then firmly tamped into the render to give an even-textured appearance over the whole wall face.

Where unpainted pebbledash is concerned, the appearance depends on the colour and texture of the mortar, the ratio of stones to mortar, and the appearance of the stones themselves. It is therefore difficult to achieve a good match, and repairs are often highly visible.

Understandably, owners often find a patchwork effect difficult to accept, and as a result there is a tendency to overpaint repaired pebbledash, substantially changing the character of the building and its historic integrity. Pebbledash repairs must therefore be carried out by skilled conservators and backed up by mortar analysis. In some cases it may be possible to avoid repairs by injecting with a fine hydraulic grout or other consolidant.

Where unpainted pebbledash is suffering from surface cracks, layers of dirt may hide some cracks and cleaning may be necessary. The selection of the most appropriate method of cleaning will depend on the nature of the dirt layer, but generally the use of solvents and degreasants in conjunction with gentle washing are likely to be the least damaging, provided that care is taken to avoid saturating the material.

Edwardian roughcast, since it is based on hard cement-rich mortars, displays much the same problems as pebbledash. However, it is usually painted over, and so repairs are more easily hidden.

Before carrying out any repair, it is important to consider the cause of the problem. If the original detailing and the original materials are at fault, repairing as found may be inadvisable. For example, is a flashing required to prevent moisture ingress? Or is the use of a dense cement-rich render itself causing the problem?

There are many cases where really important historic buildings have been treated with a cement roughcast or pebbledash in the 19th or 20th century which is now causing problems. Damp finds its way in through cracks and is then trapped, causing the underlying structure to deteriorate.

In a situation such as this, where a modern cement render is obviously inappropriate, the natural reaction would be to replace the render with a softer and more porous lime-based alternative that can allow the building to breathe.

However, cement renders tend to adhere to the substrate extremely well, and separating the two can result in the loss of the underlying face, causing more damage than it prevents. It is therefore essential to start with a test panel to determine whether complete removal is a practical solution. There are many cases, from medieval church towers to fine Georgian terraces, where the decision has been taken by conservators to leave a cement-based render in situ, and to maintain it as a waterproof coat rather than risk removing it.

Pebbledash and cement render have been widely criticised in recent decades for being ugly, too hard, impervious and highly damaging to historic fabric. However, as this article shows, they are an important feature in the architectural vocabulary of the Edwardian period, and original examples deserve better understanding and careful conservation.

Roughcast Rendering Services

Roughcast Rendering Service Overview

Roughcast Rendering is a decorative render finish which is very commonly used in England, in Australia it not a finish
that is applied to homes often. Once a roughcast render finish is applied to the wall
it will give the wall a thick textured look. It is particularly useful in areas that are exposed to the elements as the render thickness
allows for protection against harsh climates.

Below is an image of how roughcast render looks, it highly textured and comes out from the wall

What is roughcast rendering exactly?

Roughcast is made up of a lime cement mortar mix with tiny stones which is thrown against the wall to create a rough textured finish.
In Australia a roughcast render commonly excludes the stones. This finish is
a lot more popular in Australia then actually adding the stones. Roughcasting is also known as harling or wet dash, and it is a cost effective way
to coat your home and give it a textured finish.

Roughcast Rendering Repairs

If your roughcast needs to be repaired, it is never possible to make sure it 100% matches because of limitations on knowing exact mixtures and additions
were previously used. Though with experience we can make sure to make sure it matches as best as possible.

Benefits of Roughcast Render

  • Weather resistant layer of render to cover your brick work
  • Cottage/Olden Style render look that is low maintenance
  • Can be painted to any colour
  • Can be done in a variety of thicknesses and textures

If your roughcast needs to be repaired, it is never possible to make sure it 100% matches because of limitations on knowing exact mixtures and additions
were previously used. Though with experience we can make sure to make sure it matches as best as possible.

In Summary

If your looking to Roughcast render your home, contact Rok Rendering today. We are experienced in Roughcast render finishes and can work with you
to get your ideal finish.

Our Process

Timeline and Cost of Project

The cost and timeline of the project will be set in the quote, though time may vary due to weather

Why Rok Rendering

You don’t render often, so when you render do it right with the team
at Rok Rendering. With three generations of experience in the rendering
industry you can be assured you are in good hands.

Cement Rendering is one of those things that is most noticeable when the job is done wrong or not a professional standard. For home owners cement rendering is a renovation to their house they might do once or twice in a lifetime so Rok Rendering prides ourselves on delivering an excellent rendering project outcome for all of our customers.

When hiring a tradesman there should be no guess work when it comes to the quality they offer, expectations should be set before the project and met at completion. Repairing external rendered walls is a very common call out for the team at Rok Rendering, with a lot of our work being in the realm of restoration. Hiring tradesman is complicated and confusing enough, no one wants to be quality checking a tradesman they are paying!

At Rok Rendering we can come to your property and provide you with a solution to your problem. We only use the best material and our work is always of the highest quality. If you would like to work with a cement rendering company that you can trust call Rok Rendering today on 0452-523-921
or contact us using the online form by clicking here.

The quality of you render remains long after the invoice is paid!

90,000 TOP 5 interior design software for jack-of-all-trades: RemPlanner, Coohom, HomeStyler, Planner 5D and PRO100 | Furniture and interior design

In our new article, we will look at the best design programs for those who want to plan the design of their apartment with their own hands. They will be useful to all jacks of all trades who want to create the most comfortable and cozy atmosphere in their home.

We will look at 5 online design programs, each with its own pros and cons for a particular consumer. You may need to use two rather than one program at different stages for a full-fledged design project, depending on the specific function and complexity. But in general, the market for online programs for craftsmen, designers, and just families planning repairs is rapidly developing towards simple interfaces that are understandable to everyone, including non-professionals. We hasten to please, as a result, it is possible to make a design project in the program in 24 hours.

RemPlanner (Russia)

The most practical program for an apartment design project is RemPlanner, which was created by a team of professionals from Russia. There are all the tools for creating all technical plans: wiring pipes for water supply and sewerage, electrical wiring, as well as some additional schemes (warm floor, screed, plaster, partitions and dismantling, etc.). In total, your design project will consist of 18 sheets, like a real product of a professional design studio. At the same time, the program interface is simple, and the speed of the program is very high. You can master all the nuances over the weekend. It should be noted that both on the Russian and on the international market, it is RemPlanner provides a DIY technical design service along with an online planner and a simple level 3D visualization. While other programs are aimed primarily at creating beautiful visual effects.

Therefore, if you want a repair, and not just beautiful visualizations, it is RemPlanner that will help your family do without a designer and at the same time make the project of high quality and practical. The finished drawings can be transferred to the construction team without changes, and it is on their basis that any BTI plan specialist will create a redevelopment plan for you to legitimize. Imagine, you can design an apartment in the program in a few hours!

Who will suit : those who want to create a full-fledged classic technical apartment renovation project, with a simple 3D visualization.

Furniture library : furniture library schematic.

Operation speed : very fast.

Composition of the design project : layout + 3D visualization of a simple level (no rendering) + all technical drawings (18 sheets).

Program website: https://remplanner. ru/

Coohom (USA)

Functionality, including the possibility of planning, combined wall and floor decoration, unusual ceiling design, a huge catalog of furniture and finishing materials, is very pleasing here. Coohom has only one drawback – the lack of technical drawings, like RemPlanner (instead of electrical wiring, Coohom has a simple lighting plan, and there is no plumbing, sewage and other schemes at all). The exception is wall and floor decoration schemes. If you dream of creating a professional apartment design project with your own hands, you should know Coohom is an excellent choice.

But even more impressive is unlimited mid-quality rendering, and with a paid subscription you get 300 renderings per month in 4K, which is at the level of visualizations of projects by leading interior studios. This design program is also available in Russian.

Best for: for anyone who wants to create the most modern design project with luxurious free rendering.

Furniture Library: perfect free furniture library of 15,000+, and in the paid version, it expands several times.

Operating speed: high.

Design project composition: layout + excellent 3D visualization + free and paid rendering (but no technical drawings!).

Program website:

HomeStyler (China)

The next free design software in our selection is HomeStyler. It is similar in function and type to the simple version of Coohom, but made in China. This program is popular all over the world because it has an intuitive interface and ease of learning. By the way, it works with an average Internet speed and on simple computers, although the level of 3D visualization at the planning stage is high here. Professional-level rendering is also available. True, all the advantages of the program can be found only in the paid version.

We recommend HomeStyler to those who accidentally didn’t like Coohom, because this program obviously has fewer functions. Nevertheless, both programs deserve a place in our TOP programs for handymen.

Suitable for: for those who want to quickly and easily create a furnishing project.

Furniture Library: is an excellent library of modern trendy furniture.

Operating speed: high.

Design project composition: layout + 3D visualization + paid rendering.

Program website:

Planner 5D (Lithuania)

In this program, you can easily sketch a room plan of almost any complexity, you can edit the landscape, which is not available in all programs, as well as make HD renders and use both 2D and 3D modes for work. Among the minuses – a catalog of 5000+ pieces of furniture is available only in the paid version. True, the interface itself is very simple and understandable even for a beginner. There is a very large Russian-speaking community on the official website, since the program was made in Lithuania and was primarily focused on the CIS market.

Suitable for: for those who want to quickly start drawing, but were not going to implement the project with a team (there are no technical drawings here)

Furniture library: medium quality and paid only.

Operating speed: high.

Design project composition: layout + 3D visualization + paid rendering.

Program website:

Pro100 (Poland)

Pro100 is a program for cutting furniture from any sheet material. It is suitable for those who dream of making their own kitchen or, for example, a built-in wardrobe. Visualization is implemented using the KRAY module, and the New Nest add-on has super-professional material accounting for complex models.

Suitable for: those who want to master the profession of a furniture designer, and not just make an apartment renovation without the hassle.

Furniture library: no library.

Operating speed: high.

The composition of the design project : a full estimate for the implementation of pieces of furniture made of sheet materials (kitchen set, for example) plus a layout plan for the arrangement of furniture, but there are no working drawings for the design project of apartment renovation.

Program website:

How A Plague Tale: Innocence frame is rendered


As with my other research, let’s start with an introduction. Today we’ll take a look at the latest game from French developer Asobo Studio. I first saw a video of this game last year when a colleague shared a 16 minute gameplay trailer with me. The “rats against the light” mechanic caught my attention, but I didn’t really want to play this game. However, after its release, many began to say that it looks like it was made on the Unreal engine, but it is not. I was curious to see how rendering works and how much the developers were inspired by Unreal in general. I was also interested in the process of rendering a swarm of rats, because in the game it looked very convincing and, moreover, is one of the key elements of the gameplay.

When I started trying to capture the game, I thought I would have to give up because nothing was working. Although the game uses DX11, which is now supported by almost all analysis tools, I was not able to get any of them to work. When I tried to use RenderDoc, the game crashed on startup and the same thing happened with the PIX. I still don’t know why this is happening, but luckily I was able to do a few captures with NSight Graphics. As usual, I raised all the parameters to the maximum and started looking for frames suitable for analysis.

Split frame

After making a couple of captures, I decided to use one from the very beginning of the game to analyze the frame. There is not much difference between the captures, and besides, I will be able to avoid spoilers.

As usual, let’s start with the final frame:

The first thing I noticed was a completely different balance in this render event game compared to what I’ve seen in other games before. There are a lot of draw calls here, which is fine, but surprisingly few of them are used for post-processing. In other games, after rendering colors, the frame goes through many more stages to get the final result, but in A Plague Tale: Innocence, the post-processing stack is very small and optimized to just a few render / calculation events.

Game starts frame by rendering GBuffer with six render targets. Interestingly, all render targets are in 32-bit unsigned integer format (except for one) instead of RGBA8 colors or other data-specific formats. This was challenging because I had to manually decode each channel using NSight’s Custom Shader feature. I’ve spent a lot of time figuring out which values ​​are encoded into 32-bit targets, but it’s possible that I’m still missing something.

GBuffer 0

The first target contains some shading values ​​in 24 bits, and some other hair values ​​in 8 bits.

GBuffer 1

The second target looks like a traditional RGBA8 target with different material control values ​​in each channel. As far as I understand, the red channel is metalness (it’s not entirely clear why some leaves are marked with it), the green channel looks like the roughness value, and the blue channel is the mask of the main character. None of the captures I made used an alpha channel.

GBuffer 2

The third target also looks like RGBA8 with albedo in the RGB channels, and the alpha channel in every capture I made was completely white, so I don’t really understand what this data is supposed to do.


The fourth target is interesting because it’s almost completely black in all my captures. The values ​​look like a mask of some vegetation and all hair/fur. Perhaps it has something to do with translucency.

GBuffer 4

The fifth target is probably some kind of normal encoding because I haven’t seen them anywhere else, and the shader seems to sample the normal maps and then output to that target. With this in mind, I did not figure out how to properly render them.

Depth from GBuffer 5

Mask from GBuffer 5

The last target is an exception because it uses a 32-bit floating point format. The reason for this is that it contains the linear depth of the image, and the sign bit encodes some other mask, again masking the hair and part of the vegetation.

After the GBuffer is complete, the depth map is downsampled in the compute shader and then the shadow maps (directional cascading sun shadow maps and point light cube depth maps) are rendered.

Twilight rays

Once the shadow maps are complete, the lighting can be computed, but first the god rays are rendered into a separate target.


At the lighting stage, a compute shader is executed to calculate SSAO.

Illuminated opaque geometry

Lighting is added from cubemaps and local lights. All of these different lights, combined with the targets rendered above, result in a lit HDR image.

Pre-render elements

Pre-render elements are added on top of the lit opaque geometry, but they are not very visible in this scene.

After accumulating all the color, we are almost done, there are only a few post-processing operations and UI left.

The color resolution is reduced in the compute shader and then increased to create a very nice and soft bloom effect.

After compositing all the previous results, adding camera dirt, color correction and finally tonal correction of the image, we get the colors of the scene. The UI overlay gives us the image from the beginning of the article.

A couple of interesting things to mention about rendering:

  • Instancing (geometry duplication) is used only for individual meshes (it seems that only for vegetation). All other objects are rendered in separate draw calls.
  • Objects appear to be roughly sorted from front to back, with a few exceptions.
  • The developers seem to have made no effort to group the draw calls in terms of material parameters.


As I said at the beginning of the article, one of the reasons I wanted to explore this game was the way it rendered a swarm of rats. The decision disappointed me in some way: it looks like it was made by brute force. Here I’m using screenshots from another scene in the game, but hopefully it doesn’t contain any spoilers.

As with other objects, there doesn’t seem to be any geometry duplication for the rats, except when we reach a distance where we switch to the last mesh level of detail (LOD). Let’s see how it works. In rats



LOD2 there are 4 LOD levels. Interestingly, at the third level, the tail is bent towards the body, while the fourth has no tail at all. This probably means that the animations are only active for the first two levels. Unfortunately, NSight Graphics doesn’t seem to have the tools to check this.

Without rat instancing.


In the scene shown above, the following number of rats is rendered:

  • LOD0 – 200
  • LOD1 – 200
  • LOD2 – 1258
  • LOD3 – 3500 (with duplicate geometry)

This lets us know that there is a hard limit on the number of rats that can be rendered in the first two LODs.

In the capture I made, I couldn’t find any logic linking rats to individual LODs. Sometimes the rats closer to the camera are not very detailed, and sometimes the barely visible rats are in high detail.


Plague Tale: Innocence is very interesting in terms of rendering.