Today, most homes use factory manufactured roof systems. The cost of your roof depends on which roof form will you choose. The roof has to be robust enough to carry a heavy load and to be resistant to the various weather conditions.
Here are three of most common roof shapes used today and their prices.
Fink Trussed Roof
For most situations, fink trussed roof is the cheapest solution. It is identified by “W”-shaped formation of cross beams and supports within the triangle base formed by the rafters and ceiling joists, which requires regular weighted truss.
The cost of fink trussed roof is about £966.67 for 17 trusses with bracings, bindings and truss clips plus £462.00 for labour (carpenter plus mate) for one and a half day. In total, it would cost £1,428.67.
You could significantly reduce the roof costs if you cut the time of the labour on the site. For example, you can get light trusses up on the wall by yourself, saving approximately a half a day’s labour. Also, sorting out the piles of lumber by size and use will save you a day of the expensive carpenter’s time.
Attic Trussed Roof
Attic truss replaces “W”-shaped supports within the triangle base of basic fink trussed roof with upright supports which are closer to the eaves. This creates an open space along the length of the roof with storage section and sloping ceiling.
Because of this difference, an attic truss is heavier and requires a bigger timber to support this design. It cannot be easily manhandled, and you will need a crane or some other form of lifting assistance. And that affects the costs of roofing.
You will have to spend £2,769.74 for 17 trusses with bracings, bindings and truss clips, plus £616 for labour (carpenter and mate) for two days, and additional £325 for a crane. In total, it would cost you £3,710.74 in total for a decent Attic Trussed Roof.
Unfortunately, you can’t avoid the cost of crane hire for the construction of attic trussed roof, but you could save on the roof coverings and insulation.
Purlin and Spar Roof
The most expensive form of roof is purlin and spar (or cut and pitch) roof, and understandably so. Aside from its sheer elegance it also requires a significant amount of lumber which is constructed on site with the timber size determined by the structural engineer.
Because the rafters need some support (they lack the struts support from the triangle formed by them and ceiling/floor joists), this is provided by heavy timbers on each side of the roof. The truss ranges across the mid-span between the eaves and the ridge.
Purlin and spar roofing requires a large pile of lumbers that cannot be manhandled, not even in one day. It is a one week job which will significantly increase the costs of labour hired.
The cost of sawn lumber necessary for the roofing is £2,448.6. The cost of labour (carpenter and mate) for one week is £2,156 thus making a total cost of £4,604.6.
If there’s a way to save some money on purlin and spar roofing, the solution would probably be to cut the labour costs on the site. You could help the carpenter by sorting out the piles of lumber by size and use.