Q Before my parents finish the interior of the geodesic-dome house in which they live, I must stop the small leaks that plague the cedar-shingled dome. Rainwater tends to run along the edge and up under the shingles rather than down onto the next plane of shingles. How can I correct the problem? Eric Toews Janesville, Calif.
A Connecticut cedar roof specialist, in a booklet prepared for the Red Cedar Shingle & Handsplit Shake Bureau, Seattle, writes: ''The only structure that I can think of that would be harder to shingle than a geodesic dome would be a 747 in flight.''
In most professional wording and details, the booklet, entitled ''Geodesic Dome Shingling,'' describes the techniques for wood-shingling a dome. It emphatically says to avoid amateur or inexperienced roofers, since even the experts get confused about one-third of the way along.
Since the data are both technical and abundant, you may want to get in touch with Marshall Ritchie of the Seattle trade organization. The address: 515 116th Avenue, NE, Suite 275, Bellevue, Wash. 98004. You can reach him by phone at (206 ) 453-1323.