To discuss your project give us a call on 01392 861763

Passivhaus performance data

Find out more about the passive house standard of building.

We have an ever growing database of information relating to the temperature and relative humidity of a passivhaus building. Externally we’re using a Davis weather station to produce a weather file and to monitor the internal conditions at the centre of the house.

We’ve also installed temp/rh probes in to the timber framed walls. These are in the service void, in between the OSB and the UdiFLEX wood fibre wool, at the interface between the UdiFLEX and the UdiTHERM  wood fibre boards (300mm from OSB) and also at the junction between the UdiTHERM and the UdiSPEED wood fibre boards (400mm from OSB). There are a set of these sensors on each elevation (e.g. N,S,E,W). If you’d like to see the house and how it is constructed see our Flickr page.

The construction of the walls are (from the interior) 12mm Fermacell, 38mm service void, 15mm taped OSB3, 300mm UdiFLEX wood fibre wool, 100mm UdiTHERM wood fibre board, 40mm UdiSPEED wood fibre board, 7mm UdiPERL self coloured render system. The U-value is around 0.1 W/m2K.

We’ve had a few issues with stability of the connection between the sensors and the computer which is logging data but we seem to have this under control now. Apologies for the holes in the data, hopefully this will disappear from here on in.

If anyone would like the data please contact us. I’ll host it in a public dropbox and send you a link.

CPD Training

We offer CPD training for architects practices across Devon and Cornwall.

Software Modelling

We offer dynamic heat and moisture modelling as well as condensation risk analyses.

Building Plan Review

If you have some plans and would like our opinion on which materials would be the best for you, contact us.


Back to Earth is a natural building material supplier. We're not your typical builders'​ merchant though and instead work closely with our clients during the planning, designing and building phases of projects.

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