One of my lingering childhood memories is helping my Dad set out profile boards for a major house renovation we did (only the floor and part of a wall remained in the house, and we lived in it while it happened!). Dad was a builder by trade, and we used a simple clear hose-pipe with some water in it to transfer the levels around the profile boards.
My task was to try and maintain the water level against the datum mark while he took the other end of the hose around the house and marked level at his end. The difficulty was waiting for the water to stop oscillating in the hose.
Times have moved on and we’ve recently purchased a new level (a ZipLevel Pro 2000) that also uses a hose. Modern technology has been bought to bear on this age-old method of transferring levels, and now the hose contains both a liquid and a gas, and the end of the hose has a digital readout.
It allows us to read or transfer levels over an area based on the length of the hose – a radius of 30m.
The earthquake has generated a lot of work inside buildings, and getting our optical level set up so that we have line of sight to everything is always a challenge (and sometimes impossible if the building is being actively used). The new level doesn’t require line of sight, so it’s a bit more flexible.
The trade-off is that accuracy is reduced a bit – back to 2mm per measurement, so when you come to us with a levelling job, we’ll check what it’s required for, and then choose the best method to get the job done.
And by the way, there’s no waiting for the levels in the hose to stabilise – fantastic!