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Stuff you might need for the clay plastering job

So, if you are using earth from onsite, it will need sifting. For the first and second coats this doesn’t have to be super fine, through a 1 to 1.5cm mesh is adequate. We made a ‘riddler’ for large volumes from an old rabbit cage. The earth was easier to riddle when it had dried out a bit but hadn’t had the chance to go rock solid (then it needs hammering to break up the clumps). We started out using secondary hand riddlers to get it down to a finer grade, but found that this wasn’t really necessary for the first two coats, so long as you didn’t have ultra sensitive feet tramping the plaster (wetsuit boots are excellent!).

Source in the sand, again for the first coats it doesn’t need to be super fine, builders sand is ok.

Prepare the fibres. If using straw this needs to be chopped up, which is actually pretty time consuming/ heavy on tools that aren’t really designed for that use. We found an electric grass strimmer in a very large plastic tub works best, but watch out for the vents getting clogged and motor overheating!

Figure out how you are going to mix the plaster. It’s possible to hire a special paddle mixing machine, which might be worth it for big quantities. We constructed a mixing pit using 4 bales to make the sides and a tarpaulin to contain the material in the middle hole. We had a lot of fun stomping together the plaster mixes, especially when friends were involved, but it requires energy and enthusiasm for sure and music helps a lot!

Buckets, trugs, wheel barrows and similar are really useful for carting batches of plaster and ingredients around. The number you need will depend on how many people you are likely to have plastering at once. Also having a consistent designated ‘measuring bucket’ thats kept clean, helped us keep track of ratios of ingredients in each batch.

A hose with mist attachment and quality pump action hand misters are really useful for wetting and re-wetting walls and well as cleaning up tools, hands, etc.

Consider how you’ll apply each type of plaster. We found a big masonry brush or soft dust pan brush good for applying the slip coat. Hands were the preferred method for the first scratch coat, with thin gloves to protect from poking straws in nails. The second coat we used hands again, but in hindsight would have combined that with a large long darby plastering trowel and maybe even a big spirit level: this would have made for flatter walls. For the third coat we used standard plastering trowel and hawk (little flat bit of something to hold the plaster on, we just had scraps of ply, or you can buy them). Near the end we needed to replace one of our trowels and bought a good quality large trowel – 355mm x 120mm (14” x 4 ¾”), which we got on well with and was loads quicker for big areas, with a smaller one still useful for fiddly bits. For finishing we used sponges (small washing up ones were fine) and small circles of damp proof course plastic for polishing. A ‘polishing stone’ sounds like it would also have been worth a try, and if you’re lucky enough to have straight walls by the final coat, a plastic trowel would be great for this.

You will need ladders and/or scaffolding to safely reach all the areas that need plastering.

If you’re plastering an area with surroundings that matter, it is worth contemplating the likelihood of mud getting everywhere and taking preventative measures first. We put boards down at the base of the walls where possible which helped to an extent, but we’re still cleaning up now. If you can treating any timber frames etc in the area first with varnish/ paint/ oil before you start is a good idea – those areas have been a lot easier to clean than those which we didn’t. You could go whole hog and cover up everything, though remember this is a long process!