Main Span
This is where the building is the same height at the rear as at the front. We will normally go up to a maximum main span of 8m and any main span over 6m will need a truss roof construction.
Main Span with Rear Aisle
This is where there is an aisle on the rear allowing you to get a greater depth of building but also keeping the ridge height down. The roof pitch on the aisle is usually slightly shallower than the main roof and it can be as deep as is practical. We will normally go up to a maximum main span of 8m and any main span over 6m will need a truss roof construction.
Aisled Barn
The central main frame usually has a high eaves height and then there are aisles either side to increase the internal floor space We will normally go up to a maximum main span of 8m and any main span over 6m will need a truss roof construction.
Main Span with First Floor with Central Post
First floor options can be fitted into most buildings but the larger the main span and greater the roof pitch, the greater the useful area upstairs. There is a central post under the tie beam to help take the load of the floor. We will normally go up to a maximum main span of 8m.
Raised Plate without Central Post
This design gives you a little extra room in the roof compared with the Main Span with First Floor. The maximum main span for this frame type is about 6.4m although larger spans have been done using steel RSJ’s bolted to either side of the oak tie beam.
Sling Brace
This design gives a 1½ storey building but you have the sling braces to incorporate into you space upstairs. The maximum main span on this design is about 6.6m. This frame type does not lend itself very well to go around corners in either an ‘L’ or ‘T’ shaped configuration as there are eaves beams at waist height.
Lean-To
This is where there is a wall plate attached to an existing structure to pitch the roof on.
Monopitch
This is like the lean-to design except it is totally free standing and self-supporting.
Flat Roof
This is a standard flat roof design and is used if you have low height restrictions. It is often used with glazed lanterns on top to give light inside.
