VPON FLASHBACK: Winter Weatherization Tips  
Compiled from contributions from Robert Walker, Robert Riversong, and Moshe Braner
Originally published in Fall 2006 editions of the VPON Monthly
Cold weather is here again and it is time to tighten up your home.  About three quarters of energy used in New England homes is for heating and the greatest heat loss, by far, is from infiltration or air leakage. Here are several tips for free or low-cost measures to help you button up your home and save energy and money this winter. If you need help with these tasks you can hire certified professional weatherization specialists to conduct an audit and air seal your house.  For a list of contractors, see the Efficiency Vermont website.

NOTE:  Homes do require a certain amount of fresh air to keep occupants healthy.  Mold build up and back drafting of flue gases can occur in extremely tight houses without adequate ventilation, which can cause illness or death. Fresh air is best supplied in a controlled manner through powered and programmed fresh air vents.  For more information contact a professional home performance specialist.

o Most infiltration takes place as warm air rises and flows out openings high in the house, pulling cold air in through leaks low in the house. These leaks are easiest to find on cold days and are usually very cost effective to repair. Feel for cool drafts coming in low areas - where the sill meets the foundation, around low  doors, windows and protrusions for pipes and wires. Hold something that smokes, like incense, and look for smoke being sucked out along potential openings - attic hatches, upper floor windows and electric outlets, etc. Seal all high and low openings with weather stripping, spray foam or caulk.
o  Install all storm windows and doors - close and latch them tightly.
o  Caulk closed all leaky windows and exterior doors that you never open.
o  Cover leaky windows that you do want to open in the spring with an interior plastic "storm" product, like Tyz-All, available at Energy Federation Inc. (800-876-0660, www.efi.org).  Tyz-All can be removed in the spring and reused next winter.  It will usually pay for itself in one year.
o  Weather-strip ALL exterior doors, including attic hatch, bulkhead door and doors to cold cellars and crawl spaces. Check and replace weather stripping when worn.
o  If your exterior doors jiggle when closed, move the striker/latch plate closer to the door-stop so the door closes snuggly against the stop or add new weather stripping that snugs up against the door.
o  Make sure all fan-driven exterior vents (dryer, stove, bathroom, etc.) have an exterior flap that closes, and clear vent flaps of lint and other debris so they close tightly when the fan is off.
o  Close chimney and fireplace dampers when not in use.
o  Close interior doors and turn off the heat to any rooms that are unused during the winter.
o  Feel the pipes coming off your hot water tank.  If you can feel any warmth from the pipes, insulate them with foam pipe insulation available at your local hardware store.
o  Setting your thermostat back at night and while you are gone during the day will save you about 1% on you heating use for each degree set back.  Using a programmable thermostat to do this will allow you to bring the heat back up to a comfortable temperature before you get up in the morning or return home.
 
The highest return on weatherization investment (that anyone can afford) is to caulk and weatherstrip and gasket all building envelope penetrations to reduce infiltration. Second highest return is to insulate or add insulation to the basement/first floor and/or ceiling/attic.
 
Many people can do these themselves with:
    - expanding foam at the foundation-sill joint
    - fiberglass or rigid foam insulation at band (perimeter) joist of first floor
    - fiberglass insulation in first floor if uninsulated (unless basement is insulated)
    - installing or improving weatherstripping at all doors and windows (or installing shrinkwrap plastic interior storm or Mortite clay caulk on windows)
    - installing gaskets in all outside wall electric outlets
    - caulking at or behind baseboard and ceiling cornice trim on outside walls
    - adding blanket or loose-fill insulation to attic
These interventions might cost from $25 to $500 for a do-it-yourselfer and will offer a payback of one month to one year.

And here are some additional thoughts:
* If any windows are single-pane, definitely worth adding a second pane (storm window).  If cannot, then at least add a plastic sheet as a second pane for the winter.
* cover windows on the North side (and all sides at night) with tight-fitting insulated curtains.
* If there are any chimneys/flues that are not used, need to make sure they are plugged tight.  If fireplace is used, plug when not in use.  Some old space heaters have a large opening where room air enters, gets mixed with the combustion exhaust, and then goes up the flue.  Even when the heater is off, the room air keeps flowing up the flue.  There are gizmos available (about $200) that are inserted into the flue and have bi-metal fingers that open when hot, close when cold.  Better yet to replace that sort of heater with a modern type with "sealed combustion" (see below).
* If any space heaters (gas, wood, kerosene) take their combustion air from the indoors, check whether it is possible to arrange the air supply from outdoors (or the basement).  This avoids sucking warm indoor air up the chimney - it is inevitably replaced with outside air that leaks in somewhere.  Not only is this a loss of heat, it also is a loss of moisture, making the indoors too dry.  Outside air supply makes the heater in effect a "sealed combustion" device, that does not interact with the indoor air.  Modern forced-vent heaters use concentric pipes for air intake and exhaust, but separate pipes works too.