Fees for piles, grade beams and slabs-on-grade for large construction project

[pbc825]

I've designed a number of piles, grade beams and slabs-on grade in the past. Typically they're for projects that are smaller and our rate/fee schedule is time based. We're quoting on a large construction project, and I'm wondering if there is any advice on a fee schedule based on some percentage of the construction cost. If the contractor is installing $500,000 of piles then I'm not going to charge $2,000. I have the number of piles, linear distance for the grade beam, area of the slabs-on-grade to base the fees on.

Also, what risks are associated based on %-of-construction fee schedules? What comes to mind is being inundated with field questions.

Thank you in advance for your response.

 

[dik]

Foundation design is a high risk area of construcition and the fee should reflect the risk. I would think that the minimum fee should be in the order of 0.5% and depending on the complexity, maybe, as high as 1%. Do you have a good geotechnical report? and, what are the consequences of there being a little settlement? anything critical?

Dik

 

[pbc825]

We have the geotechnical report with recommendations for all structures. It's from a reputable geotech firm, so I'm not as worried about liability. There are clay layers, but that's typical for this area.

So next question is how to estimate the construction costs of these three items (piles, grade beams, and SOG). Does anyone have advice or a resource I can look at for these? I could potentially estimate the construction costs, but I'd prefer some reference material on the matter.

 

[dcarr82775]

I agree with dik. Long ago you could reasonably expect 1%, but nowadays I think you are doing ok if you can get 0.5%.

As for costs, if you know some contractor's ask them for some estimates of cost. There is always RS Means, but that is a bit of a crapshoot unless you modify the heck out of the numbers via the seat of your pants method

 

[WARose]

I usually take about 3 passes:

1. The percentage based approach you are talking. (Sometimes that can give numbers really out of whack though.)

2. Number of drawings. And X amount of hours per drawing (and that includes drafting and engineering). The X variable can really vary based on the project type. (X*hourly rate to get fee.)

3. Just a raw guess based on past experience.

The highest of the 3 I will run with as my bid. (Unless I really need the work, then I might take a lower one.)