The Kellogg College Hub building, which looks set to become the first Passivhaus for Oxford university and an Oxford college, is now over halfway through construction, with the main building shell, and windows now in place. Here are some progress photos from my recent inspections.
Getting wall insulation installed correctly has been a key part of the work so far. Gaps between and behind insulation boards result in thermal bypass, which leads to significant discrepancies between predicted heat loss, and real performance. The photos below show EPS insulation boards (white) fitted below the DPC. The pink material is expanding foam used to help secure the EPS boards, as well as fill any remaining gaps. The EPS boards have been cut to fit using a hot-wire cutter to provide a clean, straight cut. The work was actually carried out by the site carpenters, whose skills at cutting timber are well-suited to the task. Thanks to the Speller Metcalfe site team for their dedication so far to a ‘gap-free’ installation.
PIR insulation being fitted into the web of a timber cassette. More carpentry skills on show here to ensure a snug fit.
Insulated timber cassettes above brick level provide a means of fixing the decorative metal frieze back to the main structure.
Air tightness membranes and tape being applied to a column on the south facade, in preparation for windows being fitted. The membranes will then be taped to the window frames (using air tight tape products), to provide a continuous airtight line.
The triple glazed windows are now in place, and work has begun on insulating and air sealing around the frames. Once taping of air tightness membranes is complete, the building will be ready for its first air test. More to follow!