The engineers agreement with the employer will usually require him to provide the employer with as built record drawings of the completed structure.
Normal practice is for the RE or his staff to mark all amendments or additions in red on a copy of the contract drawings, the original master copies of the contract drawings then being amended. This is not entirely satisfactory because not all contract drawings are relevant or sufficient for record purposes. To make a good set of record drawings may involve discarding a number of contract drawings;
and using cut-and-paste methods to make up a single drawing from parts of contract drawings, or producing completely new drawings. Foundation drawings which have been prepared on site to show the contractor precise dimensions and levels for foundation excavations should be included among the record drawings.
Adrawing showing important details of construction can often be made up from copies of sketches supplied to the contractor. Such details can be invaluable in tracking down the possible cause of some after-trouble, such as damp penetration.
In general record drawings should give:
a good detailed layout plan of the project;
a detailed foundation plan;
floor plans for inside of buildings;
plans showing the location of everything underground and what depth it is;
details of construction where these are hidden from view.
Where new drawings produced on site are ultimately required in a digital format, this may have to be carried out at the engineers head office.
It is not necessary to show all the minutiae of construction which can be seen or measured on site after construction is completed. Copies of reinforcement drawings are usually supplied separately bound from the record drawings.
Their main purpose is to show what size and spacing of reinforcement was used. They cannot show the exact position of bars.
On clearing up the site supervision organization, all drawings superseded and not applicable to the finished works should be destroyed. This is important, because if any drawing remains of some proposal not adopted, confusion may later be raised as to how a structure was actually built. This can give rise to serious difficulties when, for instance, later repairs have to be undertaken on a dam, or tunnelling below a structure has to be undertaken. The position of all services underground should also be marked to avoid trouble when additional services have to be laid later.