I was asked if we'd found similar stencil patterns as we did at our newly acquired house in Krumlov also at the Lake house. The answer is yes - here are a few pics (from last year) to show you.
This kind of research is always something very exciting as one peels the layers - or, indeed, as they fall off once you touch them! One imagines the generations that lived there before us, and contemplates one's own mortality. The house stood here for centuries, and will stand long after we had gone. And one day there will be someone that starts peeling the wall and finds our own thin layer that passed briefly through.
But what is the correct procedure once you find the layers? Should you strip the whole wall down to the stone or brick, and start new render from scratch? Well, some do, but we try to find a more respectful way. The conservationists here divide between two schools of thought:
1/ carefully uncover different layers in different places on the wall as best as possible, then photograph them and/or trace them. Knock off anything that is obviously about to fall off, then make good the bare bits, and cover the wall with new paint, lime based. Then make fresh stencils copying the patterns you found, and paint the whole, or parts of, the wall with them.
2/ Having uncovered different layers in different places, carefully restore them to as good as you can make it (scalpel work is required here) and then paint them with organic penetration agent to fix them. The rest of the wall can be repaired, keeping the hidden layers undisturbed wherever possible. Then paint the wall, leaving 'windows' to the past where you have prepared and fixed them.
Here is a picture of such a restoration we did in our Prague flat. But which way we go at Lake house and the riverside house in Krumlov is not yet clear. But the main thing, while making the space suitable for living, and while making sure it doesn't deteriorate further, is to try not to destroy its history more than is absolutely inevitable. Well, at least we shall try. Which way would you go?