Attics that are open to the garage pose problems

Q. I am taking advantage of the unusual February weather in Vermont to go house hunting. I've seen several 1950s-era ranches with attached garages. What baffles me is that their attics are completely open to the garages. There are no vents on the ends of the attics in these buildings. There is no visible insulation inside the attic roof. The only insulation is on the bottom of the attic, between the boards above the ceiling. (Don't know where the bathroom vents exhaust to.)

Can you please explain why an attic would be open to the garage like this? It seems like an invitation to bugs and critters. Wouldn't this house lose a lot of heat? Wouldn't the moisture from the house condense on the inside of the roof?

If a homeowner wanted to make a house like this more energy-efficient, what could be done about insulating the attic? Should the opening to the garage be closed in, even partially? Should the homeowner always leave a hole?

A. It was a common practice in Vermont in the 1950s to leave the gable end facing the garage open when building ranches. I guess the thinking at the time was the open gable into the garage provided the attic's ventilation. I assume the builders of the time didn't give much thought to the need for ventilation or to the fact that the moisture brought in by the car in winter would contribute to moisture in the attic. I also don't think the builders ever thought about mice and squirrels nesting in the attic floor's insulation. Times have changed! Building a house this way is indeed not a good practice.

The insulation was properly installed between the attic's floor joists, but it was to the day's standards and is woefully inadequate by today's. Heat loss was not increased by this system, but it also is high by today's standards. The good part is that such open gable construction makes it easy to add insulation.

The open gables in these houses can certainly be closed, but other means of ventilation may then be required to avoid moisture accumulation and potential mold problems on the roof rafters and sheathing. The attic should be checked over several winters for condensation or frost on the roof sheathing, rafters or roofing nails. If these are present, additional ventilation should be considered.

The best ventilation system is a combination of soffit and ridge vents with an open connection between the two.

Q. Is there a way to recapture the heat or energy from sources in the home? For instance, it has always struck me that we spend all this energy to heat water to cook, wash and bathe with, and yet we let most of that energy go down the drain. I also can't stand to see the heat from the dryer vent billow out into the freezing air.

A. Recapturing the energy from the sources you mention is not easy or, in some cases, possible. You can let cooking water cool on the stove or countertop, or take a bath instead of showering and let the bath water cool before draining the tub. Laundry is primarily done with cold water nowadays, so this is no longer a source of wasted heat.

The heat from the dryer is another story. During the energy-crisis panic in the early 1970s, hardware stores sold a gizmo that was installed on the dryer vent and directed the heat and moisture into the room while taking care of the lint in a different way. It was OK with old leaky houses, which needed added moisture for the health of the occupants and furniture, but quite undesirable in today's tight houses, where moisture can already be a problem.

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Attics that are open to the garage pose problems