Limewash can be applied over previously painted or sealed exterior walls, but expect a shorter maintenance period. Reduced absorption into the substrate reduces the longevity of the Limewash. However, a simple coat of limewash is sufficient to maintain and restore the finish.
We do not recommend painting limewash over a sealed exterior wall if it's in a highly exposed weather area. For best results over previously painted exterior walls, we recommend applying a coat of a thin acrylic render product before limewashing. This acts as an absorbent layer for the limewash to adhere to on the wall and will make your limewashed wall more durable.
Surface Requirementsâš
Step 1: Make necessary repairs and remove dust and loose particles. Sand well if the previous paint has any level of gloss.
Step 2: If your walls have been patched or repaired or have a mix of materials over the surfaces, we recommend sealing over these areas with 2 coats of a water-based undercoat-sealer/primer. If large sections of the wall have undergone repairs it may be best to seal the entire wall. Sealing the wall ensures a consistent surface and prevents ghosting of patched areas coming through in the final finish.
Step 3: On previously painted exterior surfaces, we recommend applying a coat of a thin acrylic render product/ Acratex Primer before applying limewash. This will provide an absorbent layer for the limewash paint 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.
Paint Application
Step 4: 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. Using loose, free strokes, stretch the paint as far as possible in all directions. 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 1â2 hours between coats. When wet, the colour will appear darker and transparent. As the paint dries the colour will lighten and become opaque.
Notes + Tips:
Scheduling
With large expanses, it helps to work to a natural break in the wall such as a mortar join or V joint, or with the assistance of another person. 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.
Weather
Paint only with a minimum of three clear days without rain, or protect the surface from rain after painting. High-quality, natural limewash needs adequate curing time. This will be longer in colder weather and in humid conditions. The ideal temperature for applying Bauwerk Limewash is 8°â30°C (46°Fâ86°F). Do not paint if the surface and/or air temperature falls below 5°C(41°F) during application or curing.
Sealers
Generally, we do not recommend sealing outside walls. Our paints perform best when applied to absorbent materials. If you do wish to paint a previously painted exterior surface, we recommend applying an acrylic render style of product, see your local paint supplier.
Time Requirement for applying lime wash to stone surfaces
Even quite rough stone surfaces can be relatively easy and quickly painted with Limewash paint using a professional Limewash block brush. Take care to cover everything in the first coat. With any subsequent coat you can then be very fast, as it won't matter if you miss a spot here there, that has already been painted with the previous application.
Skill level
Limewash painting onto stone surfaces is a simple task and does not require any particular training. Observe the general painting tips for lime wash application, such as regular stirring of the paint and spreading out the paint. Avoid adding too much paint and trust the process: opacity will develop as the paint dries.