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Applying the first coat of clay plaster

If possible, it would be a good idea to start plastering in the least visible areas first, as it is likely you’ll get better at it as you go.

Getting the slip coat well worked into the straw is the first step – you can use gloved hands, but we found massaging it in with masonry brushes and dust pan brushes worked better. either way, It kinda goes everywhere, be warned!

We started our first plastering party getting  a load of people applying slip, but if the weather is good and especially if you’re not undercover, it will dry out quickly, so having the slip applied a little ahead of the plaster works best.
Then, when the slip is wet and sticky, work the plaster into the wall aiming for about 1cm thickness. We found grabbing a big handful and slapping it onto the wall hard, using the heal of the hand to force it up and into the bales, prodding it right in with fingers and then smoothing in and over (with wet/ slip coated hands) after was our method of choice.

Although this layer will end up cracked and bumpy etc, it is worth trying to smooth it over as you go and try to get it as straight as you can without building up the first layer too thickly.
When you’re done, sit back and wait/ get on with other things, while it dries. We had to wait about 6 weeks, but this summer was WET. Whilst it was drying some mould patches appeared, especially on exposed straw and in areas where there was low air circulation (corners). We vacuumed these off and when the wall was drier – they didn’t (and by all account don’t usually) persist, so don’t panic too much if this happens. We also started to use a fan to help dry these patches – although this can mean slightly more cracking, that wasn’t a problem for the first two coats.

Another thing to look out for: if you’re using straw as the fibre in the plaster mix: you will probably start growing mini wheat plantations on the walls unless they dry out very quickly. Again, nothing to panic about. We quite enjoyed some zen wall-weeding while waiting for the walls to dry out and again, once the moisture has gone any seedlings you haven’t weeded away will die off.