This section is from the book "Modern Buildings, Their Planning, Construction And Equipment Vol2", by G. A. T. Middleton. Also available from Amazon: Modern Buildings.
The person who checks the squaring should also carefully check all calculations on waste, and see that the results are correctly carried to the dimension column. The following example (Fig. 33), shows how the walls of a room are collected for plaster and paper.
Both the Squarer and the Checker, in addition to the mere mechanical work of squaring, should keep a sharp look out for any slip on the part of the Taker-off. For instance, two dimensions only will sometimes be found to an item which should obviously be measured cube.
The Checker should be particularly careful not to omit any of the figures in the timesing column. It is astonishing how easy it is, when the Squarer has omitted one of these, for the Checker to fall into exactly the same error.
All the dimensions having been squared and checked, the next operation will be that of "Abstracting," which consists in transferring the squared dimensions to the
Abstract sheets are double foolscap size, ruled in vertical columns.
One of the most important rules for the beginner is to use plenty of paper. Ability to gauge how much space will be required on the various sheets for each particular job is only to be gained by practice, and the time and worry wasted on a cramped Abstract far outweigh the value of a little extra paper.
In a large office it is particularly necessary to write the name of the job in the middle of the top of each sheet; otherwise there is a possibility of one of them getting mixed up with the sheets belonging to another job.
The name of the trade should be written at the top left-hand corner of each sheet, and the sheets numbered in each trade; as, for example, "Bricklayer No. i,"
"Bricklayer No. 2," "Carpenter No. 1," "Carpenter No. 2," etc.
For the order of the Abstract, which, as before stated, should be that of the Bill, the student is referred to the Chapter on Billing.
The beginner will find it a good plan to take a separate sheet for each heading, such as "Supers.," "Runs," "Nos.," etc., as he can then easily add another sheet to either without destroying their proper order.
Having headed the sheets, look carefully through the dimensions and enter the headings of the principal items in each trade, and as many others as you can, leaving plenty of space between the items in which to introduce any others that may occur in their proper order.
Extreme neatness and clearness, especially in writing figures and keeping them in their proper columns, is essential at this stage, not merely for the sake of appearance, but in order to ensure accuracy. Long casts cannot be made correctly with any certainty if the tens occur beneath the units or the inches beneath the feet; nor if 3's are written so as to be mistaken for 8's or 5's.
Items that are intended to be "written short" in the Bill are entered on the Abstract, as in Fig. 34.
Each column should be followed by a column for deductions (when such are likely to occur), as in Fig. 35.
Whenever a total on the Abstract is carried to another column the original column should be crossed through as shown.
The person who checks the Abstract should check these transfers, ticking the transferred figure in red, and crossing through the original column in red as indicated by dotted lines.
As each item is transferred to the Abstract the Abstractor should run his pen through the description of the item on the dimension sheets. By running a line through the description of the item instead of through the figures there is less liability to miss items where one dimension applies to two or more of them. The person who checks the Abstract should tick the transferred figure on the Abstract in red, and run a rea line through the item on the dimension sheet, parallel to the black line of the Abstractor. Red lines are represented by dots in the following example (Fig. 36):-
Abstracting may be done either trade, by trade, one trade being taken at a time; or the items may be abstracted consecutively, each being transferred to its proper trade as it is reached. The latter is the more usual and the better method. The Abstractor keeps the whole pile of Abstract sheets in front of him, turning to each one as he requires it. A little practice will enable the student to do this very rapidly, as he soon gets to know what items in each trade will appear on the left-hand side, and what on the right, and so turns back the top sheets either from the left or right-hand edge until he comes to the sheet he requires. When the carcase and finishings have been kept separate on the "Taking-off" he will only need to have the Abstract sheets of either the one or the other in front of him at one time.
Every item to go into the Bill should be noted in some form in its proper order on the Abstract. For example, in some few trades, such as Bellhanger and Gasfitter, an Abstract can often be dispensed with, and the items be billed direct; headings should, nevertheless, be made for these trades, and a note made under each in red, - "Billed direct."
The Abstract should start with an index, which, however, cannot be completed until the Abstract is finished.
Then should follow the "Preliminaries." If any or all of these are taken from the Specification, or from a previous Bill of similar work for the same architect, as is often done in practice, write the heading of "Preliminaries " just the same, and make a note under it,