ok, so what is passivhaus ?
the passivhaus standard, first established by building physicists in germany some 25 years ago, has been rigorously tested + refined since then
adopted internationally by forward-looking designers and clients, it is now being used for a wide range of buildings - from houses to schools + from new-build to refurbishment.
in the UK, it is still in an earlier phase of adoption - although thousands of passivhaus projects exist
some simple aspects of the low energy / passivhaus approach are illustrated here:
and living proof below that PH does not equal soul-less...
a norfolk social housing PH scheme by parsons whitley >>>
of the standard are derived from scientific research to find a building-fabric based approach achieving exceptional warmth and comfort
derives both from super-insulation of all external elements
- walls, roofs, floors, windows + doors + minimising cold-bridges
- and high levels of airtightness to enable controlled ventilation
is achieved by both warmth, the lacks of drafts through excellent airtightness, and comfort ventilation - whole-house mechanical ventilation with heat recovery [mvhr]
most uk passivhaus designers are working in an open source way, sharing their rapid learning on this pioneering UK approach
for the technically minded, the following standards are a guide to passivhaus design, although every scheme is modelled in great detail
cosy - very low ‘U’ values: ± 0.1 w/m2k
comfortable + draft-free - 0.6 ac/h air-tightness needs to be achieved not only in theory [hard] but also in practice [much harder]
in addition, the standard rigorously designs away cold-bridges - the little ways that heat escapes through the structure
the whole design is achieved using specialised software - the PassivHaus Planning Package [PHPP]
but equally important is the quality on site - needing special attention to details such as airtightness membranes
enerPHit barn conversion, crickhowell | 2016
located in the brecon beacons, the site offers an unusual combination of rural peace and village facilities - completed 2016