Heat rises. Such is the oft-quoted bit of wisdom used to justify preoccupation with attic insulation in houses and dismissal of the importance of basement insulation. This basic axiom is not entirely accurate however. Warm fluids (gases or liquids) will rise, this describes how heat moves via convection. Convection heat losses occur from leaks in a non airtight building envelope and in air exchanges through mechanical systems and envelope openings (door and windows). The proper use of air barriers and sealants eliminates or reduces this heat loss. This is not however the only manner of heat loss. Heat also moves via conduction and radiation.
Conduction occurs when heat travels through solid matter, from an area of higher temperature to an area of lower temperature until a uniform temperature is achieved. This transfer of heat can happen in any direction, up or down, and always from hot to cold. This is the main source of heat loss in a foundation as the concrete foundation walls are in contact with the warm air inside the house and the cold ground outside the basement walls. The heat inside the house will want to travel tot he cold side of the foundation to achieve equilibrium, however the ground being an almost infinite thermal mass will continue to draw heat from the basement. The use of insulation, which is merely any material with a series of voids which breaks the thermal bridge used in conduction, stops or limits this transfer of heat.
Continue reading ‘Heat loss myths’
Izmo the Gizmo
I am continually surprised at how beautiful my daughter is! She has found her feet and, like her old man was at that age, is fascinated and enamoured with them!
I was reading a
post today by Keith Farnish over at the Earth Blog about shrinking the economy. He made a point about how the worldwide economic crisis is affecting all countries and classes and doom is closing in on our collective monetarily driven lives and that somewhere in the Amazon some undiscovered tribe is blissfully unaware and going about their lives as they always have, free of this thing called an “Economy”.
I started thinking about a post I wrote called “Chicken or Egg” about the use of fossil fuels and advent of Keynesian economics and about why “tribal life” without money (not necessarily technology) isn’t considered a serious option. I think one of the main reasons is that we are so focused on macro societal, political and economical control that we have lost touch with how we best operate, on a familial and tribal level. A tribe of people of say less than 200 can exist without money, everyone contributing as they can and using their talents and strengths to benefit the whole, because the group is small enough that slackers or those not doing their fair share are easily spotted and easily pressured into contributing. Also, such a group is easy manage, and their needs can be met by a small area geographically.
Continue reading ‘Macro Economics and Tribal Peer Pressure’