A saltbox can have many variations. Some styles have a very short and steep front slope with a long and more gradual slope on the back. Others use almost the same angles on both sides, but if you cut one side short; this gives a lot of internal space for a storage loft on one side of the barn or shed, especially with a high peak. Some saltbox farm sheds leave the short roof side open for easy access by tractors and other implements while still providing weather protection.
Traditionally, saltbox barns and sheds are built with the long slope facing the prevailing wind, or the direction most snow and rain will come from. One theory says the saltbox style originated with colonial New England fishermen because the long slope facing the ocean provided maximum weather protection. The saltbox name, however, originated in the roof style's resemblance to the shape of the wood boxes used in colonial times to store salt.
Saltbox roofs are very weather-resistant. Because of the slope angles or pitches, they tend to shed water and snow very effectively and are less subject to buildups of "ice dams," frozen spots near the eaves that accumulate and hold runoff behind them. Saltboxes tend to have fewer leakage problems than some other roof styles.
The saltbox style can be covered with almost any type of roofing. Cedar shakes and shingles were widely used in New England, largely replaced later with asphalt and composite shingles, because these materials are cheaper and easier to install. Many saltbox barns and sheds are roofed with corrugated metal, aluminum or galvanized steel. Some even use membrane roofing, a plastic or rubberlike material common for flat or low-slope roofs.