1. Materials used in a roof and roof finishes

2. Trussed Rafters http://www.solentrooftrusses.com/roof-trusses
Trussed Rafters are now used for the overwhelming majority of domestic roofs constructed in the UK,
2 - Can use up to 40% less timber than a traditionally formed roof.
3 - Reduced labour costs on site due to the amount of pre-fabrications, releasing site joiners for more complex areas.
4- Quick erection of the roof structure enabling other trades to commence quickly
1 - Made from timber – the only truly renewable building resource.

3. Timber roof with PURLINS
Purlins, and the associated struts, are used to give some additional support for the rafters. The purlins run at right angles to the rafters, the associated struts are positioned under every forth rafter to attach to a joist above a supporting wall below.

4. Tiles are attached to battens with nails through holes built into each tile.
A breathable membrane allows your roof to breathe, meaning you won't need traditional ventilation.
It's suitable for use as a full supported or unsupported underlay beneath your slate or tiles, on warm or cold non-ventilated and cold ventilated roofs. A good breather membrane can improve energy efficiency - saving money on bills - and provide durable protection against condensation, water and air infiltration.
Tile battens

5. Tile Felt
Felt tiles can be used on non-habitable buildings as a quick attractive roofing material.
Come in a range of colours and textures depending upon the aesthetic effect desired.
Roof tiles are designed mainly to keep out rain, and are traditionally made from locally available materials such as terracotta or slate. Modern materials such as concrete and plastic are also used and some clay tiles have a waterproof glaze.
Roof Tiles
There are a wide range of roof tiles available to complement any type of building. They are made from a range of materials
Tiling video

6. Three layer felt construction
Roofing Felt
Roofing felt (felt paper, asphalt felt paper) is a sheet material impregnated with bitumen (asphalt), similar to tar paper, used in building construction. The term felt comes from the historical method of making the base material.
Three layers of overlapping felt. First layer id nailed to the OSB roof and other layers glued in place with bitumen adhesive. The final layer often has chippings on and is of a thicker higher quality grade.
Three layer felt construction
Video of three layer felt flat roof in construction.
Details on how to construct a three layer roof.

7. Plastic PVCu is by far the cheapest and thus the most popular option.
There is a choice of colours and profiles (half-round is the cheapest), as well as different sizes.
Advantages: It’s cost effective, and a good system should last 25 years. Some models mimic cast iron quite well.
Disadvantages: Cheaper systems may need replacing ten years on. The rubber seals used to join sections often shrink and crack.
Downpipes take the water from the guttering to a drain.
Home gutters are long, narrow tubes used to reroute rain that falls on the roof of a home or building. The gutters funnel the water to the downspout on the ground where it's directed away from the foundation of the home

8. Cast Iron
Cast iron was the main material used before the advent of plastics. It’s still available, though used mostly for conservation work.
Advantages: It’s very long lasting – many 19th century models are still in good working order – and looks great on period-style homes and barn conversions.
Disadvantages: It requires repainting at least every five years and is expensive
Metals
A surprising variety of metals are used for rainwater goods, copper, galvanised steel and aluminium being the most popular.
Advantages: All of the above metals promise many years of maintenance free service and look great on contemporary-style homes.
Disadvantages: Their effectiveness depends on how well they are installed: many people experienced gutter issues after the prolonged snowfalls in 2010, and often the cause of the problem was that the screws used to fix the guttering simply weren’t strong enough to support the extra loadings

9. 1. What is a kingpost?
2. What is a purlin and why is it used?
3. Draw a common roof truss.
3. What is the purpose of a breather membrane in a roof?
4. Explain the advantages of using roof trusses over on site joinery of roof timbers.

10. 6. What are tile battens used for?
7. What is tile felt and when and where can it be used?
8. Which materials are used to make roof tiles?
9. Which materials are used to manufacture rainwater goods?
10. What is the purpose of guttering and downpipes?
11. Explain the three layer felt construction technique for flat roofs.?