Engineer Talk - Session Concepts#

This week’s engineer talk lays out some basic concepts that it is important for the group to understand, because they affect which of two major paths a community building might take in future. The talk is about why we heat buildings, and especially, what makes people feel comfortable. After a discussion with our first set of engineers, we provide simple bullet points for the talk, a memory aid list of the six elements of thermal comfort, and a few details that could be useful.

If you would like more support than this, please ask - we’ll be happy to provide what you need. We can write up just a bit more further information with technical links as required, for instance, see

Bullet points#

  • We heat buildings mostly to make people comfortable

  • Thermal comfort isn’t just about air temperature!

  • If you’re surrounded by cold surfaces, they take heat from you

  • Some materials warm up (and cool down) quickly when you turn the heating on. Stone does not.

  • Problem: how do you make a stone building feel warm if it doesn’t make sense to heat it because it’s mostly empty?

  • Make it make sense to heat it – by finding a good reason to use the building more

  • Put something very warm not too far from the people (like an infrared panel)

  • Put something gently warm right up against them (like heated seating or underfloor heating - or cats)

  • Thermal comfort is about more air temperature and the surrounding surfaces

  • Deal with the draughts

  • Make sure the building isn’t damp – vent out moist air from people breathing in there, and mind that roof!

  • Make sure the temperature doesn’t keep changing so they don’t have to keep taking clothes on and off

  • Know who’s running around and who’s not

  • What about the building? Take advice – if they aren’t damp, some of them will be just fine. Others need a minimum temperature kept.

Memory aid#

  • six components of thermal comfort (from the ASHRAE standard)

    • air temperature

    • mean radiant temperature (what we’re calling “surrounding surfaces”, includes sun)

    • air speed (“draughts”)

    • humidity

    • metabolic rate (largely, activity level)

    • clothing level

  • BUT people adapt well as long as conditions don’t vary too much (<2C)