COMMENT
17
continuous air tightness and elimination of cold bridges could be achieved. The simple layered logic of the construction system at upper level was also used on the lower ground floor concrete struc- ture, the external EPS insulation and the foundations (Isoquick).
What was the main challenge in meeting Passivhaus? Direct sun gains from the south were not possible due to the pres- ence of the adjacent Victorian terrace. Additional insulation, efficient MVHR and elimination of the thermal bridges contributed to meeting the standard.
The feedback from the PHPP (Passive House Planning Package) analysis on decisions, and how a response can be found to meet the challenge of Passivhaus, is most important. For instance, as a result of the orientation, the glazing to the west facing windows have a higher g-value (proportion of heat transmitted) as this was more important than their U-value – they are the only windows receiving sufficient quantities of sunlight. Being west-facing windows, exter- nal shading was also necessary to control heat gain in summer. Another challenge is the on-site supervision required. Careful and regular checks, as well as communication to the building team of the Passivhaus principles, are essential.
How ‘zero compromise’ was the design and were any aesthetic compromises made? We did not begin the project design as a Passivhaus but the princi- ples of the building in terms of form and concept were well suited to being adapted to Passivhaus.
Eliminating thermal bridges made detailing simpler and zero compromise on that aspect is essential.
The PHPP leads to questioning the use and number of elements in a project, and that is also a positive aspect of the Passivhaus analytical process. I was keen to have a skylight in part of the upper level; the PHPP indicated that a skylight at the upper level was not contributing to the energy performance (and Passivhaus- certified skylights were not very developed at the time). The principles had an impact on the number of windows and guided their form (windows rather than large sliding screens in this case). In the end, they were positive contributions to the design project, and made the building better.
CASE STUDY: CRE8 BARN, YORKSHIRE
Retrofit with a super-insulated timber frame structure built inside the existing building to preserve the appearance of the cow byre.
Architect’s View: Bill Butcher – Green Building Store
Why were the materials and the construction method adopted? Yorkshire Wildlife Trust (YWT) wanted to convert an existing barn at Stirley Community Farm into an education centre. To achieve the required insulation levels and make the airtightness and thermal bridging detailing easier, we decided that a ‘box within a box’ construction offered a practical solution on this project. This was achieved with an inner timber frame construction with a ventilated cavity within the existing masonry barn walls.
What was the main challenge in meeting Passivhaus? A considerable amount of work was needed to stabilise the walls and underpin the foundations of the barn. To address this problem,
ADF FEBRUARY 2017
WWW.ARCHITECTSDATAFILE.CO.UK
Lansdowne Drive © Tectonics Architects
Cre8 Barn © Green Building Store
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52
