Providing Engineering Estimates
Providing Engineering Estimates
(OP)
Does anyone use a rule of thumb on estimating engineering or design man-hours?
What about estimating time or cost per sheet?
What is a reasonable ratio of engineering and design costs to construction costs?
What about the ratio of engineering costs to design costs?
I got good at doing construction cost estimates on a previous job, but now, having to do engineering and design cost estimates, I am a fish out of water.
I know that it depends, etc., etc., but any help, O Tim, would be...um, helpful.
William
What about estimating time or cost per sheet?
What is a reasonable ratio of engineering and design costs to construction costs?
What about the ratio of engineering costs to design costs?
I got good at doing construction cost estimates on a previous job, but now, having to do engineering and design cost estimates, I am a fish out of water.
I know that it depends, etc., etc., but any help, O Tim, would be...um, helpful.
William





RE: Providing Engineering Estimates
a) A complete, detailed scope of work
b) A good understanding of what the client wants (not what you think they want or need)
c) Net profit should be directly related to the amount of risk you will undertake
Cost per sheet really depends on what you are drafting or ratio of design to construction is very inaccurate, unless you have data on many previous projects that are identical to this one... etc.
One good way to do it is to hold a scoping meeting with your client. You should start with a good scope of work. You will estimate and agree on the manhours / scope for each task in this meeting, and can't leave until finished and agreed upon. For larger projects, this has taken up to 3 days. Then go back to the office and calculate the $ based upon the agreed upon manhours and scope.
RE: Providing Engineering Estimates
RE: Providing Engineering Estimates
5 - 15% may be appropriate for civil or public works design, and you have the experience to know it works for you. However, we do a lot of work on small dams and the design can be as much as 30 - 40% of the construction cost. Design analysis and obtaining agency approval for dam construction is quite extensive, compared to the construction cost. The risk to the owner and designer is also higher and therefor demands a higher fee. I don't know what a good ratio would be for electrical design as weh3 is apparently doing.