THE ‘BUILDING LINE’
Setting-out of buildings or structures on site is done in relation to the Building Line. In its strictest sense, this is an unseen line historically allocated to every building plot, beyond which the front face of a building on that plot must not project. It is established by the Local Authority responsible for the geographical area in which the building is located. It is usually set back at a distance from adjacent highways and access roads, so that these might be widened if future development in the locality requires it. Buildings may be placed with their front elevation on the Building Line, or at any distance behind it, with the position
having been agreed with the Local Authority at the planning stage. Accordingly, setting-out for the original building will have been carried out
with the Building Line as a basis or ‘base line’ from which to work.
Fig. 49 Wooden pegs, ranging line and clout nails.
Any new or proposed masonry structure – from boundary walls, paths, retaining walls and concrete bases to house extensions, separate garages, and so on – needs a base line or reference point of some kind from which it can be
set-out and in relation to which it can be positioned. This base line or reference point might be an existing boundary line, the edge of a pavement, the wall of an existing building or a wall. The new structure will need to be parallel to this or set-out at an angle from it. Setting-out on plan and establishing dimensions and angles must always be done from a convenient base line!