Issue 39 Sept 23 - Journal - Page 65
Design Solutions
Roofglaze proposed a replacement patent glazing
system sympathetic to the existing glazing bar design. The
Museum’s Estate team took time to explore options,
considering both single and double glazing. There was
engagement with local authority conservation officer and
conservation partners, and engineers had to check that
the building had the structural integrity to support a
double-glazing design. Roofglaze was able to supply glazing
samples featuring remodelled bars and brackets well in
advance.
Specification
Over 700m² of new roof glazing was specified to replicate
the existing barrel vault layout of the roof and provides
the necessary insulation to maintain the optimum
environment for the extraordinary exhibits below.
The five-tiered barrel vault layout has a dual-pitch
lantern at the apex with vertical glazed infills.
It is constructed from an aluminium framed, thermally
enhanced, self-supporting rooflight system, SpanGard,
manufactured by the Lonsdale Metal Company.
Details:
• ThermGard patent glazing bars and aluminium
presswork polyester powdercoated in Iron Grey
(RAL 7011) for an appropriate finish with long term
weatherability
• Double-glazed, hermetically sealed units with high
performance 6mm 70/37 solar controlled heat soaked
tested toughened glazing outer panes and 6.8mm inner
panes for all sloped surfaces
• 4mm thick clear toughened soft coat Low-E glass for
vertical glazing
• Box rafter construction with invisible fixings and a
low-profile appearance
Installation
There were significant constraints. Many of the enormous
sculptures remained in situ during installation. A temporary ceiling was erected to protect the priceless collection.
Access planning with the Estate team was essential. The
Museum is open 7 days a week with staff on site from 7am
and corporate events until midnight most evenings. As
contractors we had to be very responsive to unforeseen
events, even unannounced royal visits. The project
demanded teamwork and effective communication in
order to meet deadlines.
Our choice of type of roof construction meant we were
able to keep on-site time to a minimum, completing this
complex and demanding project well within schedule.
Roofglaze has a secure manufacturer supply chain to
minimise delay and ensure the speedy replacement of
matching glass or components. As with any major
construction project damages can occur and Roofglaze
ensures panes can be swapped out immediately.
Above, V&A Porter picture courtesy of Roofglaze
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Conservation & Heritage Journal
63
