Acquire two polystyrene salmon boxes from the fishmarket: 2 pieces are needed for an IGLOO with roof, as pictured below. Scrub with soap, rinse and let dry.
The made up IGLOO will measure 30 inches long by 15 inches deep by 16 inches high. Use a sharp kitchen knife for cutting.
1. Cut all round edges off the open rim of both pieces, so that they can be fitted as top and bottom.
2. Cut round holes where you want them, top and bottom matching. A hole on the side is advisable as an additional escape route for areas with foxes.
3.Tie the two pieces together tightly at all four corners, using the present airholes. Use plastic or garden string which does not rot or stretch.
4.Cut suitable size slices from from left over pieces to force into the holes at all 8 corners.
5.If available, reinforce with waterproof tape around the middle, an additional help to stop the pieces from moving apart. Sold by packaging firms (not essential).
6.The IGLOO has one shortcoming: it is very light and blows around unless it is weighted down with bricks; window boxes, flowerpots with earth, etc are also useful. Wherever possible tie to fences, trees, shrubs and even tie up when used in a closed shed. Should it fall over forward the cat could be trapped inside. An additional hole in the short end helps prevent this happening.
7.Do not use any bedding, as it would only attract moisture and spoil the dry and warming effect of the polystyrene. Extra roof protection is not needed if the corner holes are blocked.
The IGLOO can be lifted off the ground on bricks or upturned plant pots.