Inground gutters don’t need maintenance.
When sized and installed properly, rain gutters collect water and move it away from the house efficiently. But gutters require periodic (and sometimes frequent) cleaning to remove leaves and other debris, and in snow country gutters can be torn completely off the eaves.
An alternative is an inground gutter, which diverts water away from the foundation wall. It’s out of sight, doesn’t require any maintenance, and is relatively simple to install, even as a retrofit.
Start by digging a 1-ft. deep trench around the perimeter of the house. It should be between 2 ft. and 4 ft. wide with the bottom sloped away from the house, 1/4 in. per foot. Lay the membrane in the bottom of the trench. Where it meets the foundation wall, the membrane can be held in place by a piece of pressure-treated furring and masonry fasteners. This prevents any water from seeping between the foundation wall and the membrane.
The width of the trench would depend in part on the roof overhang. If the membrane is to go all the way to the foundation wall, it should be at least wide enough to reach the drip line from the roof.
When PVC drain lines are installed in the trench along with the waterproof membrane, water can be diverted to a rain garden, dry well or swale. Michael Maines described just such a system in a Building Science blog at GreenBuildingAdvisor.
Maines used a network of PVC drain lines, which could be serviced via distribution boxes with removable covers in the event of a clog. Water was piped to a dry well measuring 8 ft. by 12 ft. by 5 ft., big enough to handle an inch of rain before filling up. When it did, excess water went into a 6-in. outflow pipe.
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