Mixed + Repaired Surfaces Guide
How to apply limewash to surfaces with repairs or mixed materials
Walls made of mixed materials, like half brick and half plasterboard, or those that have been repaired, may absorb limewash differently based on each material’s absorbency. The correct surface preparation for your materials and setting will create a more consistent final finish.
This is the right guide for you if you want to learn how to:
- limewash a surface that has been repaired
- limewash a surface made up of different substrates
- prepare your surface before limewashing
- apply limewash paint
Supply Checklist
- Whisk or Electric Mixer
- Bucket
- 4 x 14 Limewash Brush
- Prep Coat + Primer
- Limewash Paint
Lime Wash Brushes
Limewash Paint
Whisk Mixing Tool
Planning
During construction or renovation, it is advisable to schedule Bauwerk painting as the final trade to prevent damage to the final finish caused by other trades or building equipment.
The coverage of Limewash Paint over Raw Absorbent walls is 7–10 m² (75–107 ft²) per litre, per coat, with 2 coats required.
Interiors Only
The coverage of Limewash Paint over Bauwerk Prep Coat is 10–15 m² (107–161 ft²) per litre, per coat, with 2 coats required.
The coverage of Bauwerk Prep Coat over Previously Painted walls: 6 m² (64 ft²) per litre, per coat, with 1 coat required.
Exteriors Only
The coverage of Limewash Paint over Previously Painted/Sealed walls is 15–20 m² (161–215 ft²) per litre, per coat, with 2 coats required.
*Recommendations for coverage are to be used as a guide only, variation in quantity needed will depend on the porosity of the surface to be painted. We always recommend the use of sample pots for an accurate colour representation and consumption for your particular surface and light conditions.
Surface Preparation: Patched + Repaired
Materials used to fill or patch damaged walls will have varying absorbency levels compared to the rest of the wall. To ensure a consistent finish across the entire wall surface, we recommend sealing the patched or repaired areas. In cases where the wall has undergone significant repairs, it may be best to seal the entire wall. The primer prevents the “ghosting” of repaired areas from being visible through the finished paintwork and creates a more uniform look, especially if your walls are made of mixed substrates.
Interior Repaired Surface Preparation
Step 1: For internal walls, apply 2 coats of a water-based undercoat-sealer/primer to ensure a consistent surface.
Step 2: Apply 1 coat of Bauwerk Prep Coat
Exterior Repaired Surface Preparation
Step 1: We recommend applying a coat of a thin acrylic render product. For exterior render that needs patching or repairs, use a mineral render product. This will provide an absorbent layer for the limewash to adhere to on the wall. If limewash is painted over a sealed or non-absorbent exterior wall exposed to the elements, you can anticipate a shorter maintenance period.
Surface Preparation: Mixed Materials
When applying limewash on a wall made with mixed substrates/materials, you may notice variations in colour across the surface due to differences in absorbency levels of the various materials. While this can add character to the space, if you prefer a more consistent appearance, you can adjust your preparation steps accordingly. Select preparation steps based on your desired outcome and surface location:
To Embrace Variation
If your previously painted walls have gloss paint, lightly sand.
Previously Painted Interior Walls: Apply 1 coat of Bauwerk Prep Coat.
Previously Painted Exterior Walls: Apply a coat of a thin acrylic render product.
Raw Absorbent Masonry Walls: No sealer or primer is required, just dampen walls with clean water using a brush or light mist spray to ensure easy application of limewash paint.
For a More Uniform Look
Your surface should be free from any dirt and dust.
Interior Walls | Step 1: Apply 2 coats of a water-based undercoat-sealer/primer to ensure a consistent surface. Step 2: Apply 1 coat of Bauwerk Prep Coat.
Exterior Walls | Step 1: Apply a coat of a thin acrylic render product before applying limewash paint.
Prepare Limewash
- Stir the limewash well and make sure all pigment is thoroughly mixed into the paint. Do not paint from a full bucket. Decant into a larger vessel and work with only around 8cm (3in) of paint in a bucket.
- Continue to stir paint regularly while painting. We recommend a machine stirrer, like a Barmix stick blender, or an egg whisk.
- Ensure you have the correct brush for the job. Our 4×14 limewash block brush is our most popular size, perfect for all applications.
Limewash Paint Application
Step 3: Limewash
Apply 2 coats of Bauwerk Limewash Paint- Dip the brush into the bucket and flick off excess paint. The brush can hold a lot of paint, but should not be dripping.
- Start in a corner of the wall–holding the brush at a right angle to the wall. It may be best to hold the brush on the brush body, rather than the handle for more control.
- Using loose, free strokes stretch the paint as far as possible, varying the direction of strokes constantly. Let the bristles do the work. There is no need to apply too much pressure.
Limewash Paint Application
- Brush out the paint evenly in a thin coat, preventing runs or drips, while covering every part of the surface in the first coat. Maintain a wet edge at all times to prevent lines in your finished surface*. Finish each coat in one continuous application. Do not try and patch walls once the coat is finished, as missed areas can be covered in the next coat.
- When wet, the colour will appear darker and transparent. Do not compensate for this by applying more paint. As the paint dries, the colour will lighten to the chosen colour and become more opaque.
- Allow a minimum of 1-2 hours between coats. Apply a second coat faster, wet-in-wet and a lot looser. Missing spots is okay, as the first coat should have covered everything. Allow the paint to dry.
If you’re painting with our ‘whites’, maintaining a wet edge is not required. These colours patch easily and are great for spot touchups.
Cleanup + Maintenance
- There is no need for a sealer or additional top coat over the limewash. A third coat of limewash can be applied, based on your colour and coverage preferences.
- All brushes, tools, and containers wash out quickly with minimal water and without harm to groundwater.
- Following these steps ensures a natural, dust-free surface with a fantastic texture, making it easy to repaint and maintain.
Repaired + Mixed Surfaces FAQs
What do I need to know when selecting my colour and sampling?
Some of our colours may look lighter once applied in exterior light. This is normal and is due to the amount of light outside. To be sure of your colour, paint onto a board of similar material to your wall, that you can carry around the space. This method enables you to view the sample colour in different lighting conditions, while also avoiding show-through of sample areas on your final finish. Use this method if you are painting naturally breathable walls like render, lime plaster or unpainted brick.
If your rendered wall has been previously painted with conventional paint and is inside, you will require Bauwerk Prep Coat before applying limewash paint. If your wall is external, you will require a coat of exterior primer such as acrylic render. This means that you can sample onto the wall, as any sample patches will be covered with Prep Coat/ exterior acrylic render and will not show through on your final finish.
My walls are a mix of different surfaces, what do I need to know before limewashing?
When applying limewash paints directly over a wall made with mixed substrates/materials you will notice a visible difference in the colour across the surface. This is because different wall substrates are made of different materials, all with varying levels of absorbency. In some cases this may not be an issue and may add to the character of a space. However, if you wish to achieve a consistent look across the walls we recommend sealing over mixed surfaces to ensure consistent absorbency across the wall. This avoids ‘ghosting’ of patched areas showing through in the final finish.
See more detailed instructions above.
Will my limewash paint colour fade outside?
The pigments used in Bauwerk Limewash Paints are mineral-based, colourfast and UV stable. This means that our colours are not affected by the sun’s ultraviolet rays (which can cause paints to fade). Our paints have been fully tested in the extreme temperatures of Australia and the Middle East.
How much limewash paint do I need?
Limewashing over Raw Absorbent walls: 7–10 m² (75–107 ft²) per litre, per coat (2 Coats required)
Interiors Only
Limewashing over Bauwerk Prep Coat: 10–15 m² (107–161 ft²) per litre, per coat (2 coats required)
Bauwerk Prep Coat over Previously Painted walls: 6 m² (64 ft²) per litre, per coat (only 1 coat required)
Exteriors Only
Limewashing over Previously Painted/Sealed walls: 15–20 m² (161–215 ft²) per litre, per coat (2 coats required)
Note: Recommendations for coverage are to be used as a guide only; variation in the quantity needed will depend on the porosity of the surface to be painted. We always recommend the use of sample pots for an accurate colour representation and consumption for your particular surface and light conditions.
How can I create a more uniform look if my wall surface has different materials?
You can achieve a uniform appearance by properly preparing your walls, following the guidance specific to the materials and the location of the surface.
Surface Requirements
Step 1: Your surfaces should be free from any dirt and dust.
Step 2: Interior & exterior walls | Apply 2 x coats of water-based undercoat-sealer/primer over the wall to ensure a consistent surface.
Paint Application
Step 1: Preparation
Interior walls: Apply 1 coat of Bauwerk Prep Coat.
Exterior walls: Apply a coat of a thin acrylic render product before applying limewash paint.
Step 2: Apply 2 coats of Bauwerk Limewash Paint using a Bauwerk natural fibre brush. Dip the brush into the bucket and flick off excess paint. The brush can hold a lot of paint, but should not be dripping. Maintain a wet edge at all times to prevent colour overlays. Do not leave drips or runs. Continue to stir paint regularly while painting.
Allow 1–2 hours between coats. When wet, the colour will appear darker and transparent. As the paint dries the colour will lighten and become opaque.
View detailed instructions in our step-by-step guide above.