Q.
(a) What is meant by pitched roof? Label the elements of timber pitched roof and explain its terms. (10 marks)
(b) Describe five (5) types of roof finishes and specify the types of building in which it is used. (15 marks)
(25 marks, 2015 Q3)
(11.09.2015)
A.
(a) Meaning of pitched roof.
'Pitched' means 'Angled'. Refer more from:
2012 Q3b - Different Pitched Roofs
Definition from Definitions.Net:
"A pitched roof is a roof with a sloping surface or surfaces. Its angle is usually more than 20 degrees. Some definitions of pitched roof are more specific - requiring a pitch of more than 10 degrees, or a roof with two slopes that meet at a central ridge."
Elements of a Pitched Roof:
Another 3-D diagram showing the elements:
Explain the terms:
The roof framing is the structure that supports your roof. The main decision that needs to be made with erecting a roof is which material to use for its construction: timber or metal.
Timber vs metal frames
Timber is by far the most common material for house framing in Australia. This is largely due to price - a timber frame is significantly cheaper than a metal one. As a result there are a lot more tradesmen who work with timber frames and the competition reduces prices even further.
A metal frame is stronger and will stand up better to natural disasters such as fire, strong winds and earthquakes. Although a steel frame may corrode in coastal areas, metal won’t warp or rot and is resistant to termites.
Additionally, a steel frame's greater load bearing capacity may also eliminate the need for internal load bearing walls. Steel and aluminium are recyclable and, unlike timber, are often cut to the correct size before they reach the building site, reducing waste. In most modern construction, things like trusses and other large framing elements are assembled offsite and then transported to the building site.
Common roof framing elements
Ref:
Roof framing elements. Build.com.au, available at
http://www.build.com.au/roof-framing-elements
(b) 5 Types of Roof finishes.
Refer to 2011 Q7 - Floor, Roof and Ceiling Finishes Q7.
5 Types Of Roofs To Consider
Several types of roofs are available for residential construction. Different materials are chosen according to their various qualities, advantages and disadvantages. Roofing a house is quite a cost-intensive affair and you need to be prepared with sound information prior to making your investment. Here’s an overview of some of the most used types of roofing:
1. Wood Shingle Roofing
Wood shingles are also known as shakes and they are especially ideal if you appreciate naturally beautiful looks. They will gracefully age with your house while retaining their aesthetic appeal. Wood shingle roofing is quite expensive though it makes up for the cost with its durability. Most people have concerns with this type of roofing especially with issues like fire, splitting, rotting and molding. Always invest in shingles that have been treated with special protective glazes and finishes.
2. Slate Roofing
Another beautiful yet very costly roofing material is slate and is especially appropriate if your house is in the French or Colonial design style.
Slate roofing is ideally composed of thin layers of rock and as such the roof is bound to be quite heavy. For this reason it is advisable to first put in place adequate structural support. Laying this type of roof can be quite complicated for a DIY project and the installation is better off when done by a licensed contractor.
3. Tile Roofing
Tile roofing is an option that goes very well with your house if it is in the Spanish or Mediterranean design. There are two types of roofing tiles: clay tiles and concrete tiles.
Tiles are generally laid down on relatively new houses that have adequate structural support since tiles, like slates, are quite a heavy load. The services of a professional contractor will come in handy if you are not confident about taking on the task yourself.
Tile roofing is also quite costly but if properly maintained it can give proper service for up to 50 years.
4. Metal Roofing
Metal roofing options are fast gaining a good reputation in building circles despite their initially high costs. These roof types boast durability as well as low maintenance qualities that extend their life beyond other conventional roof types.
In terms of design and style you’ll be glad to know that it’s possible to get metal roofing that has been made to resemble different roofing types including slate, wood shingles and cedar.
5. Asphalt Roofing
Certainly the most affordable of roofing types has to be asphalt. Asphalt shingles that are made from the conventional highway asphalt are the least expensive. You can also invest in the costlier option that is known as architectural shingles.
Cheap asphalt shingles are not the best if you intend to have a stylish roof. They will also disappoint with their short lifespan. Architectural shingles are much more presentable.
Both of these options are quite prone to scarring and may also succumb to the occasional mildew depending on the weather. They are also not environmentally-friendly and upon replacing them you’ll need to take the waste to a landfill.
Ref:
5 types of roofs to consider. DoItYourself.com, available at
http://www.doityourself.com/stry/5-types-of-roofs-to-consider
Earlier posts.