Greenhouse, outhouse, henhouse, White House, nuthouse, coffeehouse, warehouse, meetinghouse: In all, there are more than 200 words that have "house" in them. But the one that comes to mind during summers spent on a lake or river is "boathouse."

They're specialty buildings designed to store motor boats, rowboats and other small watercraft right on the water. In its simplest form, the boathouse is a one-story, wood-frame structure that provides safe shelter for one or more boats. Boathouses also can be expanded to provide shelter for rowing and boat clubs or even living quarters for families.

Not surprisingly, Scandinavia offers some of the most historic and primitive examples of the boathouse, known there as a "naust." Norsemen would construct their shelters with crude stone walls and heavy timber roofs. Unlike modern boathouses, their structures were open to the sea and had to accommodate the dramatic change in sea levels resulting from the tide. The floors were typically rock or sand.

Philadelphia is the home of the historic and now-revered Boathouse Row on the east bank of the Schuylkill River. Consisting of a continuous row of 15 boathouses, some more than 150 years old, the one-, two- and three-story structures house racing shells and their associated social clubs.

The architectural styles are as varied and competitive as the rowing clubs that commissioned them, encompassing the primary late 19th- and 20th-century revivals, late Victorian and Gothic. Although the original wood frame structures from the 1860s were condemned by the city and reconstructed with more durable materials, including brick and stone, there again were threats of condemnation in 1979. To call public attention to the beauty and importance of Boathouse Row, computerized LED lights were added to the rooflines and the gingerbread detailing of the buildings.

Boathouses or evidence of former boathouses can be found along the shoreline of most freshwater ponds, lakes and rivers. The Thousand Islands located on the Saint Lawrence River consist of 1,793 islands ranging in size from 1 square foot to 40 square miles. These islands contain the greatest number of boathouses within a 50-mile length.

The popularity of these islands drew distinguished visitors for summer vacations and, eventually, permanent homes and boathouses to store their yachts and touring boats. Boathouses remain a unique and popular architectural building type in boating communities today despite stringent building codes and increasing environmental regulations.

This column is contributed by Gregory J. Scott, a local architect with 35 years of national experience in innovation and design.