When thinking about how your home (or workplace) gains heat in the summer, and looses it in the winter, it is important to remember the different ways heat transfers. Conductance occurs when objects of different temperatures are brought in contact with each other - allowing for the molecular transfer of heat (from hot to cold). Radiation happens at the surface of objects, where heat is transferred electro-magnetically to the surfaces of colder objects. Convection happens when the moisture in air is heated or cooled.

     When it is colder outside than inside, heat will conduct through walls, floors, ceilings, and roofs to the outside. It will also flow out in the form of heated vapour, particularly if your house does not have an adequate barrier. And, it will radiate through exposed walls, windows, doors, and roofs.

     The diagram above, from NRCan's publication Keeping the Heat In, summarizes a couple of the main 'effects' behind heat loss (and gain). The wind effect occurs whenever blowing wind creates areas of higher pressure - windward side, and lower, leeward. Air will be pushed in on the windward side of the house, and drawn out through the lower pressure side. In the stack effect, air rises upwards, creating lower pressure areas in the lower floors and higher pressure in the upper floors. Higher air pressure in the top of the house will cause air to escape out (along with vapour), leaving lower pressure in the lower floors to draw cold, higher pressure in. With the combustion and ventilation effect, heated household air is combusted in fireplaces and gas or oil burners, and it is exhausted out by fans - leaving lower air pressure inside the house drawing in higher pressure air from outside.            

     Masonry or wood homes built before the 1950's are among the most attractive, and yet they were built at a time when materials and technology limited their efficiency. Fresh air in these homes comes through open doors and windows, and through gapes, holes and cracks in the building envelope. Vapour barriers are non-existent, and the only insulation in most cases is a couple of inches of air between the outside brick and inside plaster walls. Air is an insulator, just not a very good one, and the spaces between the walls cannot be filled or moisture problems will arise. The only truly effective solution is to rebuild the walls to meet current codes, but this is very costly, and only feasible if doing a complete renovation. There are a lot of things you can still do, however, that are inexpensive and offer returns on investment between 25-100%/yr. Windows, doors, and baseboards can be better sealed, cracks and gaps filled, bricks tuckpointed, and attics properly insulated with exhaust fans if necessary or desired for summer cooling.              

     Let Village Energy's experieinced carpenters go to work for you and start saving on your heating (and cooling) bills. And, increase your home's comfort by reducing cold spots and drafts.