Ok, now that I have a little more time, I can give a better answer. This may be a little lengthy, but I will try to keep it as brief as possible. First, there are two methods. If you can get comfortable with allowing an average amount of branch per outlet, it goes very fast. Averaging can be dangerous, so be careful. If you intend to measure the branch, read the following.
I asked for a more specific question because there are several parts of branch takeoff. At a minimum, those would be listing methods, takeoff techniques, and data entry. Here is a brief description of each one.
Where are you going to list (write down) your takeoff? It could be plain paper, paper forms, computer spreadsheet, or direct entry into an estimating system. Let’s ignore other possibilities like a piece of drywall or a 2 x 4. Paper is the slowest. Organization and corrections are hard. I have actually erased right thru a piece of paper.
Computer spreadsheets are better. You can organize and make corrections more easily.
Direct entry into an estimating system is the fastest, as you skip the writing down part. However, depending on what estimating system you have, corrections can be more difficult that spreadsheets.
As far as how to list, just keep it organized. Here is an example.
½” w/2 #12 & 1 #12 gr Runs ½” w/3 #12 & 1 #12 gr Runs ¾” w/3 #10 & 1 #10 gr Runs 1” w/3 #8 & 1 #10 gr Runs
Next is the actual takeoff. You will use a rotometer, such as a Scale Master or a Scalex, The first thing I teach is to roll the most prevalent items first. If I see lots of 4 wire, I roll the 4 wire first. That gives the rest of the drawing more clarity. Next, measure runs in the same plane with small semi-circular motions. Measure the runs in different planes at right angels to the building lines. Over-roll as needed to account for ups and downs to receptacles, switches, etc. This method gives you an allowance for scrap and obstructions. It also complies with many specifications that require all conduits to be run parallel to or at right angles to building lines.
Some systems allow 2 connectors for each box. If you are not using such a system, use a thumb wheel to count a “run” every time you measure between two points. The “runs” will be multiplied by two for the connectors you need. Take note that you do not have to be extremely precise on branch. High precision is needed for feeders.
Finally, you takeoff has to be input into an estimating system. If you are still doing this part by hand, don’t. After you get over the learning curve of a system, you will save many hours on each estimate, and get results with fewer mistakes.
The key to input is once again, organization. There are many ways to organize a project for input. I try to keep it as simple as possible. For small projects, total up each type of takeoff (i.e. ½” w/2 #12) and enter it just once. If a project requires more complexity, such as a separate price for each floor, you can enter each type of takeoff once for each floor.
I have briefly touched on each main area of branch takeoff. Let me know if you need more specifics.
I do pretty much the same as chiefestimator. I sometimes use paper but usually do direct input. Also I fiqure all my home runs in pipe, and all receptacles as MC cable. As chief said you don't have to be real precise with this part of the estimate, as that material is generally cheap and quick to install. Concentrate more on your feeders with how you will actually install them.
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