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)