Don’t Show Them the Cellar Honey

As an energy auditor and energy remodeling specialist, I have been focusing most of my attention on our charming classic homes. You may be the proud owner of an old Cape, Colonial, or “New Englander.” Chances are, that old girl has probably had some cellulose blown into the attic or walls. Windows may have been replaced or storm windows installed. A wood or pellet stove may have been thrown into the mix. These measures have probably had some limited success in reducing the energy costs of your antique home.

Where your real problem resides, however, is in the cellar and crawlspace areas. The skeletons that lurk below are the Achille’s heel of your home. These are the very foundations that we are ignoring (pun intended).

A river running through it

Cellar areas are typically high moisture zones due to unsealed foundation walls and floors. Why not throw in an old spring running its water course across the dirt and concrete floor? Condensation runs rampant and mold and mildew have a field day. To make an appropriate analogy; your home has cold, wet feet.

At one time, fiberglass insulation batts may have been desperately hung from the underside of the floor joists. This usually proves to be a vain attempt to seal off cold air intrusion. Over a relatively short period of time, moisture works its woe on the paper barrier of this product and the whole mess starts to look like ugly stalactites draping down towards the floor below.

The whole environment spirals downward from here on in. Rodents may take up residence in the dirty pink mass. Condensation degrades structural wood members and shortens the life spans of furnaces and oil tanks. Boilers and furnaces are operating in a chilled air space which also cools down air ducts and hot water radiator piping. Earthy smells waft their way into the living areas above from the raw earthen floors below. The list goes on.

Shut the cellar door, the party stays upstairs

Your home acts like a thermal chimney. Cold air is drawn from the cellar, up through the house, and out the roof. Brrr … A nice warm cap of cellulose is valuable in the attic, but be sure to include some insulated rubber boots in the cellar to keep the chill off and the feet dry. How?

Enter spray foam insulation and foundation drains, the couple with a promising future. Insulating foundation walls and floors properly with closed cell spray foam can have dramatic effects on the energy dynamics of these old homes.

Flowing water should be escorted out of the cellar beneath a vapor barrier. Humidity values can be brought down well below 50%. Once air sealed, the entire cellar becomes part of the conditioned air space of the home. Furnaces are operating in warm and cozy environs and are yielding more heat output. Condensation and mold spores are eliminated. The thermal mass of the building structure can work its quiet magic and the home is considerably more comfortable to live in. Heating costs are noticeably reduced.

Now, when the inside cellar door is opened, heat comes rolling up the stairs! This old girl has probably been given the gift of another hundred years. So, invite them over for wine and show off that transformed cellar!

Doug Walker is an accredited Building Performance Institute energy auditor. He also is a builder/remodeler that has been involved in energy efficient construction techniques for over 30 years. He lives in a passive solar home with his family in Harrisville.