Hi,

I've been doing a bit of landscaping over the summer (?) and have
terraced my garden with a few low retaining walls. My intention was to
buy some stone (or concrete) blocks to work as coping stones, but I've
failed to find anything suitable and so have bought some preasure
treated wood to do the job instead.

Having messed up some skirting a few years ago by not correctly
measuring the angles of the corners of the room and assuming them to
be 90 degrees (please, nobody else do this) I would like to get the
wooden wall tops fitted with tighter joints, but how do I accurately
measure the angles?

Does anyone have any foolproof techniques to measuring internal or
external angles of walls for use when calulating mitre cuts? Ideally
i'd prefer some method whereby I don't have to go out and buy a
special angle measurement tool (ashamedly I don't even have a sliding
bevel), and i'd even consider maths as a way out so long as it works!

Any thoughts?

M