Cherry Tree Cottage insulating hempcrete plaster:

2015 Oxfordshire

contractor

The stone walls of the existing house were very thick and the client didn’t want to loose too much internal space.

The walls were curvy and full of character and again the client wanted to retain this, cast hempcrete would have been too square and too tricky to cast at just 100mm.

At the time I did not own a spray machine so I used the hempcrete plaster recipe and plastered approximately 100mm thick of hempcrete.

The plaster is built up in 10-20mm layers wet on wet letting the last layer set enough to hold the next layer before going onto it. The maximum it can be built up like this is 150mm.

The recipe was 60 litres of Battichnvre : 100 litres of hemp shiv : 55/60 litres of water : 15 litres of 0-5mmsharp sand.

The thermal conductivity of this mix is 0.13W/m.K

The insulated plaster is then covered with any standard 2 coat lime plaster.