Rich,
I feel that you should always do a detailed bid. There are just too many variables that can make a difference. You work too hard to take a chance on losing money on any single job. Take the time and do a detailed estimate.
You referenced Mike Holt?s book. I highly recommend that you purchase the book. It will give you a good understanding of the basic estimating process.
Unfortunately for you, and regardless of what others say, there is a lot to consider when completing a detailed estimate.
I don?t believe in square foot estimates. Construction factors, the quantity of different types of assemblies, labor rates, material fluctuations, etc. can have a dramatic impact on your cost.
I don?t believe in unit pricing either. Once again, construction factors, labor rates, fluctuating material prices, etc. can change from job to job.
I know it?s going to be a big surprise but I?m a big believer in computer estimating software (As is Mike Holt). I would suggest that you check out the programs that Mike lists as the major estimating programs. I?m pretty sure that you can download free trials of them all. Check them out. If nothing else, it will at least give you a good idea of what is involved.
Following is a list of some of the areas that you should be aware of:
Construction Factors ? The construction of the house makes a difference on installation times.
-- For example: A ceiling light rough-in will take longer in a 1st floor ceiling that is constructed of dimensional lumber (2x12s) than it will in a 2nd floor ceiling that is constructed of open web joists.
Material Type ? Are you using conduit or romex? #12 or #14? Standard devices or Decora devices? Etc.
Material Cost? What are your materials going to cost you?
Direct Labor ? What is your direct labor cost for the project.
-- You need to have a basis to determine how long the installation will take. I personally believe the most accurate method is to use labor units. A labor unit is the amount of time that each piece of material, assembly or labor only installation takes to install.
-- Some people prefer to use each employees billable rate per hour rather than their actual pay rate per hour. Whatever you do, make sure to include each employees burden costs.
-- If you have an apprentice, or anyone that produces less than an average Journeyman, don?t forget to calculate how much additional time the project will take to make up for their lack of production. This is an area where a lot of people leave money on the table.
Additional Labor- What additional labor, over and above the direct installation labor, are you going to incur? Ex: Deliveries, job set-up, material ordering, paper work, travel time, etc.
Tools ? Do you need to purchase any tools or equipment for the project or do you want to apply a small percentage to account for tool replenishment.
Subcontracts ? Do you need to subcontract out any portion of the job? Ex: Security, fire alarm, concrete cut and patch, etc.
Bond ? Do you need to bond the job?
State Sales Tax: Does your state require you to collect sales tax on the bid amount? This is not the same as the tax you pay on material.
Code Requirements ? Do you know the code requirement for the jurisdiction?
-- Are you going to submit a bid price that reflects exactly what is on the print or are you going to value engineer the print so that you can give your customer a price for per plan as well as a what it will cost them for a code compliant installation?
-- If you?re unsure of the inspector?s requirements, call him up ask him. Remember that the NEC is the minimum. Every inspector has their own unique requirements. Don?t assume. It can cost you money and grief.
Take-Off ? Take-Off the electrical items from the print. I find that a spreadsheet works well for this.
-- Each column can be an assembly, I.e., Single Pole Switch, 3-Way Switch, etc.
-- Each row can be a room. I.e., Front Exterior, Foyer, etc.
I feel that you get the following benefits when doing a room by room take-off.
-- it is easier to double check your estimate.
-- You can present a Quantity Take-Off by Room report as part of your bid package.
-- You can assign the proper labor units based on the construction factors of each floor.
Include the cost of any light fixtures.
Add any misc. material that will be required.
Add for material waste and/or theft if it?s an issue.
Make any labor hour adjustments ? This can be additional labor for things like weather and humidity, ladder and scaffold, overtime, job factors, etc.
Add up your estimated prime cost ? This is the sum of material, labor and misc. expenses.
Add your overhead to the estimated prime cost. This will give you your Estimated Break Even Cost ? There are numerous ways to calculate your direct costs.
-- You can choose to assign different percentages for material ,labor, etc.
-- You can choose to use a percentage of your estimated prime cost.
-- You can choose to use a rate per hour.
-- You can choose to use a lump sum.
Add your profit to the estimated break even cost ? This will give you your Bid Price.
-- You can choose to assign different percentages for material ,labor, etc.
-- You can choose to use a percentage of your estimated prime cost.
-- You can choose to use a lump sum.
Generate a detailed, professional looking, formal proposal ? Be specific on what is and what is not included.
-- Include the scope of work
-- Reference the print date and the last revision date if applicable.
-- Include a date that your price is valid till.
-- Make sure to specify if your bid price is based on exactly what the print shows or if you value engineered the print to meet code.
Break up your bid price into the draws that you want to receive, I.e., Service, Rough, Trim. etc.
Good luck Rich.
