1.   Sumerset, one of two companies that dominates the houseboat industry, asked the federal government to test the dry stack it engineered.

2.   Sumerset, one of the two largest manufacturers in the country, developed its own dry stack design.

3.   The Coast Guard will wait until at least May to recommend a dry stack.

4.   The roof vent, or dry stack, works like the exhaust pipe on an old steamship.