Reduce change orders on your projects by attacking their primary causes: design drawings that, for whatever reason, cannot be built as designed, are not cost-effective, or have errors that increase the base bid price.

How do you accomplish this? By involving people with extensive maintenance and construction background in the design process. These experts can provide an independent review of the design documents before they are put out for construction. According to guidelines set by AASHTO, your review should accomplish these goals:

• Assure that the project can be constructed using standard construction methods, materials, and techniques.


• Provide the contractor with clear, concise plans and specifications that can be used to prepare a competitive, cost-effective bid.


• Result in a project that can be maintained in a cost-effective manner over the life of the project.

Who reviews the plans? Reviewers commonly come from three primary sources: the owner’s construction or maintenance department, an independent consultant staff member, and/or from a contractor. Secondary sources that can be used include utility companies, material suppliers, or reviewing/approving agencies. Build your review team in the planning stage, using the unique characteristics of the project to identify those most qualified to comment on its constructability.

Including the unique perspective of the construction and utility industries is highly recommended, since their expertise is finding the most economical way to build a project. Intricacies such as plan and specification ambiguities, conflicting details, resource demands, delivery problems, and suggestions to improve construction sequencing can be identified before a project becomes subject to change orders or litigation.

Be cautious, however, about allowing a contractor to have input during the design phase. If reviewing contractors are allowed to bid, other contractors may perceive an unfair advantage and delay your project by challenging the bid process. Resolve this problem by having contractors from outside of your geographic bidding area assist in your reviews.

When to involve reviewers? Involving reviewers during the preliminary design phase is optimal, since the capacity to influence design, construction, and maintenance costs is greatest at that point. Often, however, critical expertise is only solicited just prior to bid time, when it is too late to cost-effectively improve the “ability to construct” the project. Last-minute constructability reviews can result in design revisions, utility relocation delays, schedule crunches, and the resubmittal of permit applications at a point where you should be focused on completing the project, not redesigning it.

At a minimum, conduct reviews at the 30% and 95% stages of design. For more complex projects, you may want to include a 60% review.

Types of projects that warrant constructability reviews. Some owners prefer that all projects be reviewed, while others require that only moderately complex or complex projects or projects exceeding a pre-established dollar limit be reviewed. You are the best judge of what types of projects should be reviewed. You know where most of your change orders and problems exist. Use this information to reduce your risk and identify those projects where a constructability investment will make the most impact.

How Much Does a Review Cost? Data providing baseline cost comparisons are scarce and are not measured using common criteria. A small project, however, can reasonably be expected to require 24 hours for a review. More complex projects, or those for which an in-depth review is required, may incur 40, 80, or even more hours of analysis. For a moderately detailed, independent review, you can expect to spend between $1800 and $8000. Measure the cost of your review, however, not in dollars but as a percent of your design and construction expenditures.

Cost/Benefit Analysis. Measuring the benefits of a constructability review can be difficult. Good records are not generally kept, common methodologies are not available, and documented benefits have been anecdotal. Common sense indicates, however, that having an industry expert conduct even a nominal review to identify plan and specification ambiguities, quantity and unit price errors, conflicting details, and construction sequencing problems will reap benefits in excess of the cost merely by reducing the time spent resolving questions and discrepancies.

Using the above information, you can determine the timing and frequency of constructability reviews that you need to apply to your projects.

When design drawings and construction documents are independently analyzed, this assures clarity, consistency, completeness, and ease of construction. In the process, you will end up with projects that are biddable, buildable, and maintainable.

Owners that implement constructability reviews claim these benefits:

• Fewer change orders and less time spent negotiating them


• Fewer questions during bidding - less bid addenda


• Clearly understood and more complete plans


• Fewer, and lower, claims


• Competitive bids


• Identification of long-lead and short-supply order items


• Smoother permitting


• Clearer understanding of the time frame needed to construct the project


• Fewer utility conflicts


• Improved accommodations for equipment picks and material deliveries


• Incorporation of worker safety issues into the design


• Reduced maintenance costs

Increased understanding and use of innovative construction