The Naked Scientists

The Naked Scientists Forum

Author Topic: Is the calculation of the U value in architecture based on real science?  (Read 659 times)

Offline thedoc

  • Forum Admin
  • Administrator
  • Sr. Member
  • *****
  • Posts: 511
  • Thanked: 12 times
    • View Profile
james asked the Naked Scientists:
   Hi am an avid follower of you great show.
my question is on thermal movement.
I Work in an architects practice and an important equation which guides government policy and is a big part of green commitments is the insulation in buildings (big money in this equation) is the calculation of the U Value.

However have heard from some that this equation was only ever seen as a guess in one lecture a long time ago and seems to have been adopted without question.

Is this bad science?

Another equation which guides a large industry in construction is the calculation of the dew point and yet never seems to actual work.

Would greatly appreciate you laying the real facts bare.

Many thanks
James
What do you think?
« Last Edit: 21/04/2016 15:50:01 by _system »


 

Offline wolfekeeper

  • Neilep Level Member
  • ******
  • Posts: 1092
  • Thanked: 11 times
    • View Profile
There's nothing wrong with the science: the U-value is just the heat flow in W/mēK; it's a perfectly standard thing to calculate and measure.

The difficulty would be in whether the actual material actually hits the value that is being quoted, it will depend on things like humidity and age of the material. For example, double glazed windows work very well when they're new, but the gas used gradually leaks and then they don't work so well- the U-value increases.
 

The Naked Scientists Forum


 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums