Nigel, you mentioned structural
considerations. How does this tie in
with zero falls?
Nigel: A blue roof designer needs to
How does the thermal performance
update apply to a blue roof?
Chris: Unlike a traditional warm roof,
BauderBLUE is supplied as part of
a full Bauder roofing system and
therefore has a single point warranty.
the U-value achieved in an inverted Bauder’s technical director, Nigel
account for the dead and imposed roof greatly depends upon the amount Blacklock, has been an active member
loads of the system build-up and of water that passes through the of the Technical Work Group for the
the maximum potential retained joints of the insulation and sits on duration of the amendment along with
rainwater, this tends to lead to a the waterproofing, as this will cause representatives from NHBC, BBA, BRE,
concrete slab being used. rainwater cooling. This has a negative RIBA, NFRC, SPRA and manufacturers.
effect upon the roof insulation value. Nigel and Chris Roddick, green and
A detailed structural analysis of the
deck should account for construction
tolerances, settlement and deflection
Nigel: So, there is now a note that
blue roof product manager for Bauder.
suggests that not less than 10%
under load with a concrete slab level is added to the thickness of the
survey carried out to identify any insulation to take account of rainwater
back-falls prior to the waterproofing cooling. However, water on an
being installed. Hence the advice inverted blue roof might sit on the
“design a fall of 1 in 80 to achieve waterproofing for longer and with a
not less than zero”, starting at zero greater depth, BS6229:2018 states no
inevitably will lead to back-falls. correction factor should be used which
will lead to much thicker insulation
Chris Roddick
Nigel Blacklock
than is currently used. This could
effectively censure installing blue
roofs over inverted insulation.
For more information call
Bauder on 0845 271 8800
www.bauder.co.uk