Disadvantages of L shaped Stairs: 1  L shaped stairs are a bit more difficult to build. 2  A support is typically required for the landing in a L type stair. Often this is built into the surrounding walls so it goes unnoticed. 3  Handrails for these types of stairs require more skill and planning to construct. In climates where basements are used, stairs are typically stacked over each other for efficient use of space. Since basements are often used for storage, large items can be difficult to move in and out of the basement.
A valley roof is formed when two portions of the roof meet at an inside angle. These valleys are common to many roofs. The Cape Cod style of architecture is one type of home that is traditionally free of valleys if there are no dormer windows on the roof.
Closed-cut valley -- Even if I work toward the valley with three-tab shingles, cut valleys are faster than woven valleys hands down. With a closed-cut valley, there's no need to shingle the two roof planes at the same time. Plus, cutting the closed-cut valley shingles can happen after the rest of the roof is shingled.