The standard unit of measurement for a garden shed is a PeterCrouch. For a more accurate measurement he will roll into a ball to provide a smaller scale and I understand he will do this for a couple of chocolate hobnobs.
Using the PeterCrouch method is all very well, but surely calling on the expertise of Chelsea FC's hooligan football firm of the early 80's, the Chelsea Shed Boys would be a better bet...
if the Chelsea Shed are in need of assistance the Millwall Boot Boys are apparently happy to pass on the knowledge they have gained from decorating The Den.
Now that all the comedians are in bed you’d probably appreciate a sensible answer.
First lay down in your shed and if you can do that with straight legs and without having to bend your head, your shed in longer than you. Now take two pieces of garden stake the same size as you are tall and lay them on the shed floor making sure the ends of each stick touches each opposite wall. Now you can nail/tape the two stakes together and you’ll have the exact length of the shed. Now do the same procedure between the other two walls so you’ll have another stick the depth of the shed.
Now take the two sticks to the NMO (National Measurement Office) and they will measure them for you free of charge. To get the shed’s ground area they will need to multiply the length with the depth so don’t get the two sticks mixed up.