Jun, Jul, Aug, Mar, Apr, May, Dec, Jan, Feb, Sep, Oct, Nov
Using a tape measure, carefully mark out the pieces according to these measurements: back panel 30cm x 15cm; lid 20cm x 15cm; front 17.5cm x 15cm; base 15cm x 15cm; and two side panels cut for a sloping roof, 20cm high on the back x 17.5cm high at the front.
Once you've marked the position of all your cuts, saw through the plank. Be careful to follow the lines you've marked, as a wobbly cut may mean your joints aren't flush and the box will be draughty.
Screw the parts together to ensure a firm join, drilling pilot holes first to prevent the wood from splitting. Attach the two side panels to the back board, then the base and finally the front.
Using a large drill bit, make an access hole in the front panel, near the top (so the young are out of reach of predators). Blue and coal tits need a 25mm hole, great tits 28mm, sparrows 32mm.
Attach the lid by nailing the rubber hinge, and drill drainage holes in the base. Hang the box in 2-3m high, in a sheltered spot, ideally facing north east, east or south east.
Not all birds like boxes with a hole for an entrance. Robins, wagtails and flycatchers, for example, need a box with a front panel that covers only two-thirds of the gap, leaving an open 'window'. Simply make the front panel smaller - 12cm long rather than 17.5cm.