New build part-hempcrete house
2012/2013 Bristol
hempcrete contractor | lime render and plaster contractor
I acted as consultant to the architect of this build to assist with their hempcrete details.
The front and one side of this house was hempcrete and the rear and other side was SIPS with foam insulation- a strange combination, I can’t wait to return to see if there is any difference in feeling or performance between the hemp rooms and the foam rooms.
I constructed the softwood frame around the oak with Rob and Dan and assisted Graham Durrant in spraying the hempcrete. I did all the lime plastering with Rob and completed the lime render with the help of a local plasterer called Simon.
There were 50 cubic metres of hempcrete @350mm thick, the softwood, hempcrete, lime plaster and lime render came to £35,890.00 (bear in mind just over half of the hempcrete was rendered)
yours truly and his new mitre saw
1st day on the job getting head round the plans
stud work off the oak frame to support the hempcrete
the hempcrete doesn't touch the oak the oak
the hempcrete site 15-20mm off the oak
rear elevation
once plastered there will be a 4mm shadow gap between plaster and oak
lime plaster work
front elevation
check out the shadow gap
socket faces ready to go in
really beautiful shadow gap
the lime plaster was mixed onsite, 5 parts 0-2mm sand : 2 parts NHL2 for the base coat / 2 parts silver sand : 1 part NHL2 for the top coat, all measured by volume
close up of top coat, the very slight texture give creates reflections
tricky to plaster
gorgeous lime plaster
splayed window reveals allow more light
Oak and lime plaster is a beautiful combination
the internal scaffold was a nightmare to plaster around
the hempcrete was sprayed by Graham Durrant with my assistance
this was one of the very first hempcrete spray jobs in the UK
the left gable had the softwood frame set to the outside, then a breather membrane, then natural stone set in lime mortar with stainless steel wall ties connecting the masonry back to the softwood
there is no cavity between the hempcrete and breather membrane nor between the breather membrane and stonework (when it went up)
being one of the very first spray jobs in the UK the finish on the hempcrete was not as neat as we can get it now so it took me a bit more work in the render to get it looking just right
rear elevation
interestingly the rear of the house was in SIPS panels and nasty foam insulation (i did not do that work) it will be interesting to go back and see if there is any noticeable difference between the front of the house in hempcrete and the back of the house in nasty foam
there will be a drip bead in the render lapping over the lead work
make sure you cover up oak from wet lime
i wouldn't have needed to do all this masking up if i had used clay plaster
1st floor corridor
finished room
