[Strawbale] airtight plaster

[Dave Howorth]

I'm planning to build a loadbearing bale house next year. I'm currently
thinking about airtightness (I'm of the 'build tight, ventilate right'
school of thought). It doesn't seem to be an easy subject to read up
about, so I'd welcome any advice or pointers to materials about making
straw bale walls airtight.

I'm planning to use the indoor plaster as the main airtight barrier. It
will probably be clay plaster, though lime is a possible alternative. I
know a bit about tapes to use at window and ceiling junctions and so
forth. My main concern at the moment is about how to use clay plaster to
make an airtight barrier that stays airtight. So things like minimising
cracking and so on.

I'd be grateful for [links to] any information about practical
techniques and recipes, and information about any airtightness tests.

Thanks, Dave