3 metres of plastic pipe and 6 metres of 2 X 1 inch box section - �15
These can be bought from any scrap dealer.
20 slabs 50 X 50cm with sand and cement - �38
Bulk deliveries from a builders merchant saves time and money remember the slabs will be hidden under the shed so the cheapest will do.
Plastic shed 57 X 79 inches - �240
Preferably of a type that has the walls in 2 sections and is capable of later extension. This can be obtained at most DIY and garden outlets. There are several on the market and I can supply further details by email it required.
Six 8-inch wheels - �39
The wheels must be capable of taking the weight and stress of the run off operation. They can be bought at DIY shops. It pays to buy the strongest you can because they are obviously critical components of the run off system.
10 Metres aluminium Angle 2 � X 1 � X � inch - �63.
This can be bought from a local metal supplier and needs to be � inch thick for strength and wide enough for the wheels to be positioned without overhang or rubbing.
50 metres armoured mains cable and 2 weatherproof sockets - �55.
This was cheaper at a local DIY shop than an electrical outlet so shop around. For safety reasons armoured cable and weatherproof sockets must be used even though they are considerably dearer. It is also wise to bury the cable at least 8 inches below the ground if possible.
Threaded rod, nuts, bolts and 10 metres of 3-inch self-adhesive damp proof strip - �25
These can be bought from DIY stores. Stainless steel fixings and nylon locking nuts are preferable.
2 wooden posts and metapost brackets. - �14
Bought from any DIY or garden outlet.
Total Project Cost - �489
To secure the doors at the top I used a couple of kitchen cabinet leg adjusters which I had left over but they can be obtained at some DIY stores or alternatively ask at a fitted kitchen dealer.
Additional bracing was added to the observatory during construction using wood battening that I already had (remember those bits you put away because they would come in useful some time?)
Equipment List
The tools for the job were: -
Shovels
Spirit Level
Trowel
Tennon saw
Hacksaw
Spanners
Pliers
Tape measure
Drill & bits
After a few weeks it also became clear that the top section had not been raised enough for completely smooth run back and that it needed raising by a few millimetres. I went to a local double-glazing company and scrounged some UPVC window strip, which was glued onto the rails. This raised it enough to give a much smoother runback.