ESTIMATING FOR THE ELECTRICAL CONTRACTOR
The British General Electric Co., Ltd. sent us the following article by Mr. F. A. Sclater, extracted from the Electrical Times of 27th April, 1950, which we are reprinting as a reminder that in the matter of estimating all that glitters is not necessarily golden.
The comments strewn through this pungent article apply equally well to all tradesmen in the building industry as well as to the electrical contractor and we feel sure that the writer's conclusions will be heartily endorsed by those firms who have to submit tenders in order to obtain business.
When the Editor of the Electrical Times asked me to write an article or "Estimating". I rang up and explained to him that I was somewhat diffident as I felt that his readers would be full of expectations of finding an easy solution to one of their greatest problems and might feel very dis- appointed when they got to the end.
At the same time, I am sure that failure to estimate correctly is the main reason why so many young fellows who start up on their own come to grief after a short time.
If I spend £5 17s. 6d. on fishing tackle and go fishing for two days of eight hours, how many fish will I catch and what will be their total weight? That is the problem which the Editor has set me. Before answering it I have to ask him: Where will you fish? What is the depth and type of bottom? What is the weather? What previous experience have you?
Now there are many fishermen who already have the tackle and the experience who would be able to estimate their basketful fairly well before setting out, so the question is not really as silly as it sounds.
Fallacies
Before starting operations, let us clear away some of the muckage! In the first place, I do not believe for one moment that the firm quoting the highest price is a bunch of get- rich-quick crooks. On the contrary, I believe that the lowest lender frequently includes the same or even more profit than the higher figure. In other words, the net cast of the higher figure bears a lower percentage of profit, although the profit in cash may be the same.
Another bit of muckage-lel us face it!—is the idea that all electricians will produce the same results in the same period of time, in other words, that all men are equal.
Finally, let us appreciate that although two jobs may be done to exactly the same specification, the one installation may be first-class and the other very poor; that is to say, work- manship cannot be covered by specification.
In my early days, people used to talk of “a pound a point" and it is surprising how the phrase is still used by architects' dogsbodies and others, but more of this later.
Inquiries
Now the necessity for estimating arises from an inquiry which may take many forms, as for example:-
1.
2.
3.
4.
I note you consider our installation here should be re- wired. Please let us have an estimate of the cost. Herewith sets of plans of No. 38 Cambridge Place, W., which is being converted into six flats. Please mark the plans with the points you suggest and return them with your estimate,
Please let me have your lowest price for 90 lights and 21 heater points at 38 Cambridge Place, W.1. The work should be carried out in steel conduit with flush switches, bronze finish. The house may be converted into six flats. As consulting engineers to the Sclater Trust, we have been instructed to invite you to tender for the proposed electrical installation at 38 Cambridge Place, W.1. Specification (20 pages) and a set of plans are enclosed. Tenders should be forwarded in a sealed envelope marked "Sclater Trust" to arrive not later than the first post on the 20th inst.
There can be many variants of the above examples of an inquiry but only in the case of No. 4 can you settle down and start to work out a figure. In all the others, questions of policy must first be considered.
In No. 1, obviously the customer trusts you implicitly and you must give him a good, sound job at the right price. You might even suggest the time and material basis, using the percentages approved by the War Damage Commission.
No. 2 gives you the greatest possible freedom of action but there would seem to be a possibility that your scheme may be copied and other prices obtained on it.
No. 3 is just stupid but a very common form of inquiry, As we know, "steel tube" may cover several styles of wiring, including the best and the worst, and "lowest price" is an ominous phrase which is almost an invitation for dirty work. The last sentence appears almost to be an after- thought, but to make provision for the possibility will entail quite an additional cost.
Architects
It is a sad fact that architects (speaking generally) appear to regard the electrical contractor as a very low form of life and when savings have to be made it is generally the
-
47
electrical installation that suffers first. The trouble is that when a plumber does a bad job the pipes leak and everybody knows about it, but very often the electrician could do the job in bell wire and no one would be any the wiser. It would seem that even to-day the "electrician" can get away with almost anything and it is for that reason that reputable firms of contractors should never quote a figure that does not allow for a sound and thoroughly workmanlike job.
A good reputation is far more valuable than £100 extra profit on a particular job
Before starting to estimate, a number of considerations arise and among them are the following:-
(a) If the premises are existing, will a builder be at work at the same time; if so, are you to be a sub-contractor? If yes, then do not forget to add 1 39th to your total to cover builders' discount. Will the builder do all the "cutting away and making good," including lifting and replacing floorboards, chasing walls, etc.? If so, your labour figure should make due allowance for this.
(b) If it is a new building, then you are certain to have a sub-contract and must cover buildings' discount, Find out all you can about the type of construction, such as concrete floors, hollow tile ditto and anything else which is likely to affect your costs.
(c) Is there proper provision on the plans for your main switchgear? We have known blocks of flats where we were expected to fit all the service arrangements in a little cupboard under the stairs. In such restricted positions the work takes twice as long.
(d) Other questions to be considered are scaffolding, storage of material and transport facilities. These all make a difference.
(e) A very material factor is whether you have any previous experience of the parties with whom you will have to deal. Sometimes a job is set out before starting and goes steadily through to completion. Other people make con- stant alterations and it is almost impossible to claim additional variation orders for all of them.
(f) Does it look as though the work can proceed steadily from start to finish or will you have to keep taking the men away and then sending them back after a few weeks? Having made up your mind on the foregoing points and others which will doubtless occur to you, the next stage would seem to be to make a calculation of the load and from the total connected load deduct suitable figures for diversity on which, generally speaking, for domestic purposes the I.EE. rules form a good guide.
The next move is certainly to draw a sketch of the service and distribution arrangements showing the main switches, bus-bar chamber, if any, and sub-mains, and mark on the sketch the rating of the switches, size of conduits and cables and all other particulars.
If a full consulting engineers' specification is supplied, then all this is decided for you and if not, it is essential to design the layout of the job before you start to estimate what it will cost,
First settle the type of wiring which you are going to put forward-screwed conduit, tough rubber, metal-sheathed cable or what-not. The next stage depends very much on whether you have a complete plan of the building with the points marked or whether it is an existing building and you merely have a schedule of points. If you have a plan, you can lay out the wiring and measure exactly how much conduit, cable and so on will be required and if the building is large you will no doubt take a definite section, say one-eighth, and use this as a basis, multiplying your result by eight. snags in this procedure are obvious but on the other hand it is a great time-saver and, generally speaking-taking the rough with the smooth-works out fairly well.
The
At this stage you can start to make a list of the material required and by far the best plan is to do this on the sheets of a loose-leaf ledger.
Labour
You then reach the most difficult point of all, when you have to calculate the number of man-hours required to do the job. No one can tell you how to do this and it is clear that this is where your experience comes in and brings us to the point of the most important book which any firm can keep.
The cost book and the cost accountant are the most material factors in the success or failure of the financial side of a business and any firm which tries to economise by neglecting the careful costing of any job it carries out is asking for trouble.
Now I enjoy messing about in boats, but I know men who spend so much time scraping, painting, splicing and over- hauling generally that they never get to sea-others there are who repair all defects with a lashing or a piece of wire and sooner or later they have to set fire to their shirts to call the lifeboat.
All matters are a compromise. The cost of your "costing" is part of your overhead expenses, every job bears its propor- tion and your profits are reduced by the amount you spend but in my view accurate costing is far more valuable to a firm, within limits, than the sum actually expended.
Costing is best done in a loose-leaf ledger and at the completion of any job an analysis should be made which pro- vides the following information:-