These are the most prevalent types of shed roof design: Pent, Gable and Gambrel/Dutch Barn. In addition I have included below three of the less common roof types which you might be considering.
Before you decide what you are going to build it is worth reviewing each of the types below and seeing how they are framed. You can then decide which you are going to build for your project, based on a mixture of appearance and your own skills/expertise.
For each of the shed roof types below I have listed:
This shed roof design has the simplest form. Its single slope is suited to buildings that sit against a fence or wall. The roof is a simple beam spanning between the front and back walls. The roof pitch is governed by the choice of roof covering materials and any planning restraints. The span of the roof is limited by the strength of the timber roof joists, for longer spans a mono-pitch truss could be used.
Most common shed type of shed roof
The roof of a gable shed is a simple duo-pitch roof truss. Storage can be achieved in the roof, or headroom can be increased by raising the bottom chord of the truss to form a raised collar truss. The angle of the shed roof can vary widely from a typical 20 degrees on mass-produced sheds to 70 degrees on a high-pitched gable roof shed. (When a roof slope exceeds 70 degrees the British Standard defines it has a wall !).
The Gambrel roof construction achieved prominence in Dutch Colonial Architecture. Structures with Gambrel barn roofs allowed animals and equipment to be stored downstairs with a hayloft upstairs. Constructing a short span Gambrel roof truss for a shed is not the most efficient use of timber, however there is a big advantage in the amount of internal headroom available.
The salt box roof shed originated as a fisherman's shed and was designed for its simplicity and strength to resist the wind coming in from the sea. This shed roof design is not symmetrical, one of the eaves is a lot lower than the other. The design is an extension of the gable roof with one side of the roof forming a 'lean-to' extension or 'cat-slide' roof.
Sheds with hip roofs are similar to gable roof sheds but the end-wall slopes in so that all four faces of the roof slope towards the ridge.
Hip roof framed sheds are less common than gable roof as the framing is more complex due to the compound mitres where the jack rafters meet the hip rafters.
The hip roof shed has a visual advantage in that the sloping ends reduce the bulk of the roof, thus improving its appearance. The sloping ends do however reduce the potential for storing stuff in the roof. This style of shed roof is commonly used for pool house sheds and summerhouses where roof storage is not often an important criteria.
Curved roofs do have a certain visual appeal. There are not too many immediately apparent structural or other advantages but they are worth considering for their visual novelty.
So there we go with the most common and a few less common shed roof types. At this point you might be wondering which type of shed roof type is within your capability as a first time shed builder.
The Pent roof is the simplest shed roof design and does not require trusses. However individual rafters will need to be notched/birdsmouthed so that the rafters sit neatly on the wall plate.
The Gable, Gambrel and Saltbox sheds can all be constructed using roof trusses. These are fairly simple to construct with a simple repeatable jig, to ensure that all roof trusses are of the same dimension and fit the wall plate dimensions. The Gambrel truss is probably the most complex of the three trusses to build as it has the most joints and angles. However if you take your time and follow instructions on a good set of shed plans then it is well within the reach of most diyers.
There are a number of ways of forming a curved shed roof. Curved roofs for small sheds can be formed by simply having a flat roof with curved firring piece on to which the flexible ply roof deck can be fixed. For larger sheds a truss can be modified in a similar way. Commercial curved shed roofs use steam bent timber of curved glulam beams to give a very slick look. The curved roofs in the pictures are formed using the first two of these techniques.
Hipped roofs are more complex than the trussed roofs as they need to have compound mitres cut to support the rafters on to the hip rafter. For this a chop saw is the easiest method to use to avoid some complex marking out. Using metal joist hangers from suppliers such as those by Simpson can make the job easier but will add to the overall cost of the roof.
There are three main roof styles;
And three other less common styles.
The design of the roof will have an influence on how easy it is to build. Visit the next page on Shed roof construction to find details of a typical build sequence and how to avoid some of the more common and time consuming construction mistakes.