Sweeney Architects

Hitting the Roof

Last week we spoke about condensation, this week we are going to discuss roofs, the different styles and why they are important. After all who wants a leaky roof? Have a look around your locality and see how a roof can be the most distinguishing element of a home or business, and greatly affect its overall look and style. It is important to remember that different roof types are customised to meet certain requirements. Additionally your choice in roof style can heavily influence the cost of your building or renovation plans.

The most common roofing styles in Ireland are gable or hipped. The principle differences between them lie in the slope of the sides of the roof, and the roof-to-wall junction. Gable shaped roofs involve the meeting of two straight slopes from the ridge of the roof, falling all the way to its eave. The result is a triangular shaped structure on either the side or the face of the façade. In contrast, hipped-roofs have an even roof-to-wall junction, as the roof plane is broken is broken along the slope line, allowing for an easy wrap around your house.

The gable shaped roof is probably the most commonly used roof style, as its triangular shaped slope allows for rain, snow, leaves etc. to simply fall off the roof and away from the building. Although gabled roofs can differ in their slope or pitch they all serve the same purpose of efficient run-off of water, and therefore also protection against its damaging effects. Hipped roofs, on the other hand, are highly suitable for extreme weather conditions, as the shape of a hipped roof, along with its complex internal framing, braces against strong winds.

The roof framing of your home is either cut-roof or roof trusses, or sometimes a combination of the two. Roof trusses are roof-shaped frames that are designed to concentrate the entire roof load at the ends of the truss. This means that the trusses, actually span the distance between their two end bearing points. Although there may be walls under the trusses, they are “partition” (non-load bearing) walls. The advantages of using trusses are cost and speed and ease of installation. The disadvantage of using trusses is that there is not much usable storage space in the attic. A cut roof, on the other hand, are cut and installed on site. One of the main advantages is the possibility of extending into the attic and the storage space. On the other side, a more complicated load carrying system is required for the house. Because roofs slope you get to decide the pitch, the higher the pitch, the more roof surface you’ll have, and more roofing material required. Also , roofers charge more for steep roofs because they’re harder to work on. Typically in warm climates countries lower slopes are common while in Scandinavia steeper pitches are used to help shed snow loads. Flat roof construction is unusual in domestic houses, generally due to the difficulty of avoiding leaks.