Expose Hidden Hardscape Costs
28 Feb, 2007 By: Jamie J. Gooch LDB SolutionsA segmental retaining wall job is fairly easy to quote accurately. The block manufacturers have formulas for calculating the square footage of the wall that is to be built, and you know the material costs up front. Add in labor costs based on previous experience and you’ve got a solid quote. That’s not so easy to do you’re your client requests a natural stone wall or boulder work.
“Finding a good supply of the material is the most important first step,” says Richard Poynter, Poynter Landscaping Construction, Wildwood, MO. “Secondly, it’s a challenge to accurately price it since it’s non-uniform material. We’ve weighed the material and built mock-up walls to determine how many square tons and our waste rate so that we can price it properly in large bids.”
 Boulder or non-uniform stone walls, like the one above, can be difficult to bid correctly. (Image courtesy of Richard Poynter) |
Poynter says it’s important to be as accurate as possible when bidding on projects that include walls made of boulders. It’s easy to underbid if you’re not familiar with the extra labor involved or don’t calculate material costs accurately.
“Most stone, boulders and cobblers are purchased by weight and then sold to the client in some other way,” he says. “That conversion is easy to price incorrectly. If you’re too high, you may not get job. If it’s priced too low, you’ll lose money.”
Extra labor and equipment are other considerations.
“Large boulders are going to require equipment to place them,” he says. “That has to be factored in. They’re difficult to manage. Some are almost too small for equipment to be used, but too large for people to handle without the help of machinery.”
Machineriy needs access to the site, which might require an access road to be built., adding to the project cost.
“It’s easy for estimators to get hung up on how much wall material will be needed and downgrade the importance of the extra time and materials associated with extra excavation, clean up, footers and backfill.
Experience is the best teacher when calculating wall built from non-standard materials. Start small to get an idea of the time and materials involved.
“If it’s a big job, it could blow your margin for a month to miscalculate it,” Poynter says.
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