Among the most common reasons for moist basements and crawl spaces is an inadequate gutter, downspout, and drain system. Gutters are required at all locations where water drains off the roof. Gutters and drains need to be adequate in size and quantity to handle all but the heaviest of torrential downpours. The purpose of the entire system is to divert the water collected on the roof away from the house and its foundation. The diverted water may be drained into a storm sewer or an on-side “french drain” or similar system. It’s recommended that homeowners review the adequacy of their gutter, downspout, and drain system on an annual basis. This can be done during a heavy rain, at which time all of the water from the roof should disappear into the gutters and flow through the downspouts and the drains, without spilling over onto the ground next to the house.

Wood Gutters and Galvanized Downspouts

This was the traditional construction system employed and is rarely used today. The original wood gutters were made from old growth cedar, a product which is rarely available today. Its substitution with new growth cedar or hemlock gutters has proven inadequate. Galvanized downspouts do not tend to last as long the newer products available on the market.

Vinyl and Plastic Gutters and Downspouts

This is a commonly used material and often sold in do-it-yourself hardware stores. It is easily installed by the homeowner, and when properly installed is a good product. It is also susceptible to damage by heavy ladders, as well as long-term deterioration by ultraviolet light from the sun.

Integral Gutters

A popular gutter style in the 1960’s was the integral gutter. This system is formed by the end of the rafters and fascia in a sloped roof. The gutter is lined with a built-up roofing material and has the advantage of being able to hold a great deal more water than most of the other types of gutters. The disadvantage of this gutter style is in the potential for leaks, which can result in damage to the framing, fascia, soffit, and sheathing of the roof. In order to prevent such damage, these gutters need to be carefully inspected every few years and the lining replaced or repaired every five to ten years. Should such a gutter system prove troublesome, it is possible to convert this gutter into a standard gutter configuration at the time of re roofing.

French Drains

A french drain is a pit or trench located away from the house, filled with gravel or crushed rock. The water is carried to the french drain in a plastic drain tile and is absorbed into the ground. The french drain must be built far enough from the house to prevent any of the water from re-entering the basement or crawl space.