So, where do you start? – First, understand your building.

It’s icy cold today. Downright frigid. As I write I can feel the cold drafts run through my leaky historic house, built in 1908. The ice crystals on the windows in the kitchen sparkle in the low winter sun and remind me of the loss of heat happening before my eyes through the edges of those old panes. So I stuff rugs under the doors, and wear my snow booths inside (really cool EARTH booths bought at Buffalo Exchange recycled clothing this week, they make me feel like I live in Vail or Sweden)

But back to reality -

Basic building science explains why I feel the cold even more on a day like this where the high temperature is expected to be 18 degrees. So let’s talk about how heat moves within a building.

Conduction: easy – hot moves to cold through direct contact – like the ice crystals on my window forming as the hot moist air from the kitchen hits the cold windows.

Convection: forced air – like the blast of hot you feel when a forced air furnace kicks on and the lack of movement of air when it turns off. (See alternatives to forced air heating here)

Radiation: the heat trapped in the building mass –like from sunlight through a window or as it heats a brick or block wall. This type of passive solar in some homes can hold the heat for hours after sundown.

But not mine. Even though I have block plaster walls that theoretically should hold heat, the house is so poorly insulated that it would be deemed ridiculously leaky by any energy auditor. (See more on building science here)

So - why? How Does Insulation Work? Because building science relies on the performance of the ‘Envelope’ to truly predict how the hot or cool air will move through a home. This is basically a matter of how well the home was built as far as Insulation, Weatherization and Duct Sealing. In addition to the HVAC system which functions to force hot or cool air.

All of these upgrades are approved upgrades under the current ClimateSmart 1A Loan Program proposal as retrofits for existing buildings. Good news for homeowners looking for a place to start.

First, Insulation – most people have decent insulation in the attic, because every dummy knows that heat rises, so somewhere along the way, someone added pink here. But what about the walls? Around windows? Crawl spaces? Rooms over or next to the garage? Every home has its trouble spots. In many cases the old fiberglass batting has sunken down in the wall, leaving huge gaps with no insulation at all.

The greenest of insulation in my opinion (maybe because of my clothing obsession) is from recycled denim (link) but, it is also one of the most expensive to use in retrofits. The easiest green solution to all your insulation blues is blown foam or cellulose. It fills every crevice and can be used in most any retrofit trouble spots.

Weatherization – often homeowners think this is a great task for the ‘honey-do list’ but think again. There is more science here than meets the eye… This includes replacing old doors and windows or to create better seals in the openings through caulking or weather strips. Old fashion storm doors and windows also count as weatherization. Technically, any insulation is also known as weatherization. More on Weatherization Options>

Duct Sealing – actually, this is a possible do-it-yourselfer but be sure to get your facts & products straight. Here are some tips from Energy Star:

“Start by sealing air leaks using mastic sealant or metal tape and insulating all the ducts that you can access (such as those in attics, crawlspaces, unfinished basements, and garages). Never use duct tape, as it is not long-lasting. Also, make sure that the connections at vents and registers are well-sealed where they meet the floors, walls, and ceiling. These are common locations to find leaks and disconnected ductwork.” So the main reason to seal your ducts is that it increases comfort as well as efficiency. Learn How Here

Also, if you plan to do any of these projects yourself - check the R Value Guidelines set out by the Department of Energy.

A great local green building company for jobs like this is Eco-Handyman. They specialize in bang for your buck and always recommend starting with these basics. Then you can move on to upgrade you furnace or water heater or maybe add a green roof... Return next week for more antics from the frontline of green building here in beautiful snowy Boulder Colorado.