A pitched roof is a type of roof that slopes downwards from a higher point to a lower point, rather than being flat. This type of roof is commonly found in residential and commercial buildings and is characterized by its triangular shape. Pitched roofs have been in use for centuries and are preferred by many homeowners and architects for their aesthetic appeal and practical benefits.
Their different types of pitched roofs, including gable roofs, characterized by two sloping sides meeting at a central ridge, and hip roofs, featuring slopes on all four sides, converging at a central point
Different Types of Pitched Roof
The choice of pitched roof type will depend on several factors such as the building’s architecture, climate, and the homeowner’s preferences.
In this article, we will discuss the different types of pitched roofs in detail and their suitability for various building styles and environments.
1. Single Pitched Roof
A single-pitched roof is a type of pitched roof that has only one slope, as opposed to two slopes that meet at a ridge like a traditional gable roof. This type of roof is also known as a shed roof or mono-pitched roof.
Single-pitched roofs are commonly used in modern architecture, especially for buildings with a minimalist design. They are also popular for structures such as porches, sheds, and carports. Single-pitched roofs are versatile and can be used in various settings, from urban to rural areas.
One of the main advantages of a single-pitched roof is its simplicity and ease of construction. It requires less materials and labor compared to more complex roof designs, making it an affordable option for homeowners and builders.
2. Double-Pitch Roof
In the roof span of the roof increases above 2.4 meters, the section of common rafters becomes heavy and it makes the roof uneconomical. Originally, in the single roof, the entire load of the roof is transferred to the walls through the end of the rafters only which makes the section bulky.
In a purlin roof, intermediate support in the form of purlin is introduced so that some of the load is transferred through this purlin. This reduces the net load at the leg of the rafter and allows the section to be lighter.
We already know that the load from the roof can be transferred only by purlins as the roof only transfers the axial load. The Double-pitch Roof can be economically adopted up to a span of 4.8 meters.
Advantages of Double-Pitch Roof
- These pitched roof types are widely used for residential construction. It has become an economical solution for roofing systems and its visual appearance is really good.
- A double-pitch roof has a slope between 45° to 60° which is sufficient for effective drainage for houses in heavy rainfall and snowfall regions.
- Designing this type of pitch roof system does not require much time and effort.
3. Triple/Trussed Roof
When the span is increased, the first solution is to introduce purlins or take support over partition walls. But, if the span is much more or if the intermediate supports are not possible, then a truss is introduced. A truss is a framed structure that carries a ridge piece and provides support to purlins. In the construction of roofs, different materials can be used for truss-like timber, steel, etc.
The wooden truss supports a span of 3 meters.
Read More: Gable roof detail – Its Types, Components, Pros, and Cons
4. Lean-to Roof
Other names: Pent roof or Aisle roof or Veranda roof Lean-to-Roof is the simplest form of the pitched roof in which slope is provided on a single side only.
In this type of roof, the slope required for the pitched roof is provided by the wall itself. One of the walls over which the roof is to be supported is raised higher than the other wall. This gives the pitch or slope. Over these two unequal walls, roofing material is laid to obtain a lean-to roof.
Usability: Sheds, outhouses, and verandas attached to the main buildings. It can support a span of 2.4 meters as it is supported only on a single side.
5. Couple Roof Truss
It is an advanced type of lean-to roof. Here, both the walls on which the roof is to be supported are kept at the same level. Then, roofing is provided leaning upwards towards each other.
In the middle, they intersect at a horizontal beam called a ridge. This type of pitched roof provided for a span of up to 3.6 meters.
6. Closed a Couple of Roof
It is similar to the couple roof in structure except it has a tie beam joining the legs of the two common rafters near the support wall.
It is named as closed couple roof as the tie-beam closes the couple roof structure. The provision of a tie beam prevents the common rafters from being spread outwards. It also prevents the overturning of the walls on which the roofing system is supported.
It can be adopted for a span of about 4.2 meters or less.
7. Collar Tie Roof
It is a modified form of a close couple roof. In collar tie roof, the tie beam that is provided at the leg of common rafters in coupled roof truss is raised above and it is known as the collar beam.
The provision of a collar beam enables the roofing system to utilize the space economically. As the beam is raised, the height of the room is increased. It can be adopted for a span of about 4.8 metres.
8. Simple Roof Truss
Simple roof truss can be adopted for Span 6-9 m.
Read More: 11 Types of Wall Cladding: An Affordable Alternative to Paint
9. King Post Roof
In this roof truss, a central post is introduced that joins the ridge point to the main tie. This central post is known as the king post. The two common rafters spanning from the ridge to eaves are called principal (main) rafters.
King post supports the ridge and holds both the principal rafters together at the ridge or apex at the top. It also provides support to the main tie and prevents it from sagging.
As this truss is provided for longer spans, there is a possibility that the principal rafter may bend from the middle. To prevent this, inclined members called struts are provided.
Struts connect the middle of the principal rafter to the middle of the main tie. Here it forms a joint with the king post and the other strut. Most of the time, a king post roof truss is made up of wood, or a combination of timber and steel can also be used.
Usability: Sheds, porch, garage, small houses, etc.
King post roof truss can be economically adapted for a span of 5-8 meter.
10. Queen Post Roof
This is a modified form of king-post roof truss. As the span increases, the tie beam will experience sagging. Instead of one post at the center, the queen-post roof truss has two vertical members aligned horizontally across the span.
These two vertical posts are called queen posts. The queen posts are placed at one-third distance from the support. A horizontal member called a straining beam connects the upper two ends of the queen posts and also holds them in position.
A straining sill connecting the bottom of the queen posts is also laid over the main tie. This straining sill prevents the feet of the queen post from coming closer. The inner square formed by queen posts and straining beam can be braced diagonally to impart rigidity to the truss.
Purlins are provided on queen posts so that they aid in load transfer. This makes the queen-post roof truss lighter than the king post roof truss.
It may be adopted for a span of 8-12 metre.
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Thank you sir, For Sharing this valuable information
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I never found such detailed information about a pitched roof. Thanks for posting this useful blog. I like pitched roofs because of their aesthetic appeal and planning to build one of them. Your writing enlightened my mind about its different types and made it easy for me to decide which type suits my new building. Thank you again. Keep posting. Good luck.