Generally we do not recommend to seal the finished walls - we try to keep it as natural as possible. Sealing the wall will also require another undercoat once you want to re-decorate in a few years time. Otherwise it is just another layer or two of Bauwerk Colour paint on top of your previous application, which is very quick and does not produce any fumes. They can be added on a need to basis.

By the way, the most durable substrates in combination with lime wash paints are cement or lime based renders. Such finishes do not require any primers or undercoats, the paint is applied directly and do not mark as easily as the paint can penetrate deep into the substrate and bond there.

Many sealers rely for their seemingly magical properties on PFAS (per- and polyfluoroalkyl substances), known as “forever chemicals”. This group of synthetic chemicals are used to prevent corrosion, reduce friction and make products waterproof and stain-resistant. PFAS also show up in paint and sealants.

PFAS’ incredibly strong carbon-flourine bonds mean these chemicals do not biodegrade. Renovations will not last for ever but PFAS persist and accumulate in soil, water, air, wildlife and our bodies. PFAS have been found in human breast milk and the blood of 97% of Americans. Exposure to some PFAS has been linked to fertility problems, changes in metabolism, and an increased risk of obesity and cancer – yet so much still remains unknown about their long-term consequences.

Eroded by the elements or dumped down drains, PFAS end up in the water system. Once there, remediation – removing the pollution – is impossible. Water-treatment plants can use activated carbon to filter out some, but not all, PFAS and other contaminants, but it is expensive and requires high-temperature incineration. Most of the chemicals from that silky smooth painted wall or rust-free railing ultimately end up in the ocean.

For the above reasons we are reluctant to make recommendations, please check the ingredients of the sealant you may choose and contact the manufacturer if you want to make sure to exclude such harmful substances.

However, there may be instances where a sealant is necessary or you just prefer it that way. In such a case please choose a water based sealer that dries completely flat/invisible.

⚠️ We would recommend to do a small test area first, some sealer make the paint appear a touch darker or lighter than without a sealer.

In kitchen areas where the walls can come into contact with food it may be better to choose a different surface finish. From shoulder height upwards it should be fine to continue with lime wash paint.

We recommend to do the same for restaurants, especially where tables are set right against the wall.

Read also above: What you need to know when considering sealing a natural lime wash finish