A sheet material template for indicating positions for attaching a building panel to a supporting structure, comprising - a central portion having a first side and an opposite second side; - a handle opening arranged in the central portion at or near a central axis; - a first side portion foldably attached to the first side of the central portion by a first side fold; - a second side portion foldably attached to the second side of the central portion by a second side fold; - a first handle portion foldably attached to the first side portion by a first handle fold; - a second handle portion foldably attached to the second side portion by a second handle fold; and - a plurality of template markings (11, 12, 13, 14, 15, 21, 22, 23) adapted to indicate desired attachment points to be used when attaching a building panels to a supporting structure; characterised in that the sheet material template further comprises a handle opening arranged in the central portion at or near a central axis; and the sheet material template is adapted to be reconfigured from: i) an initial configuration in which the central portion, first side portion and second side portion are substantially co-planar to ii) a template configuration in which - the first side portion is folded about the first side fold; the first handle portion is folded about the first handle fold and received in the handle opening so as to form a first handle projection; and the first side portion forms a first building panel support; - the second side portion is folded about the second side fold; the second handle portion is folded about the second handle fold and received in the handle opening so as to form a second handle projection; and the second side portion forms a second building panel support. - a central portion having a first side and an opposite second side; - a handle opening arranged in the central portion at or near a central axis; - a first side portion foldably attached to the first side of the central portion by a first side fold; - a second side portion foldably attached to the second side of the central portion by a second side fold; - a first handle portion foldably attached to the first side portion by a first handle fold; - a second handle portion foldably attached to the second side portion by a second handle fold; and - a plurality of template markings (11, 12, 13, 14, 15, 21, 22, 23) adapted to indicate desired attachment points to be used when attaching a building panels to a supporting structure; characterised in that the sheet material template further comprises a handle opening arranged in the central portion at or near a central axis; and the sheet material template is adapted to be reconfigured from: i) an initial configuration in which the central portion, first side portion and second side portion are substantially co-planar to ii) a template configuration in which i) an initial configuration in which the central portion, first side portion and second side portion are substantially co-planar to ii) a template configuration in which - the first side portion is folded about the first side fold; the first handle portion is folded about the first handle fold and received in the handle opening so as to form a first handle projection; and the first side portion forms a first building panel support; - the second side portion is folded about the second side fold; the second handle portion is folded about the second handle fold and received in the handle opening so as to form a second handle projection; and the second side portion forms a second building panel support.