Everything seemed to be going according to schedule on a jobsite for a large multifamily housing project that included hundreds of units across multiple buildings. A manual inspection, however, uncovered that pipe sleeves throughout the project were off—enough to put compliance with Americans with Disabilities Act (ADA) codes at risk. With cabinetry and plumbing already in place, what would have been a relatively simple fix if it had been uncovered earlier became a significant amount of rework that required bringing multiple trades back to the jobsite, sending costs through the roof and triggering a cascade of delays that pushed the project far behind schedule.
This type of scenario isn’t an unusual one: Across regions and sectors, rework accounts for a significant portion of the total cost and time of commercial construction. Even minor defects can require rework, increasing costs and delaying schedules. And with $273 billion worth of construction errors made each year in the U.S. alone, rework is more than merely tolerated in commercial real estate construction—it’s expected and built in up front to project budgets and timelines.
As the plumbing sleeve example illustrates, errors can have a compounding effect, which means that preventing just one early mistake can prevent nearly a dozen negative effects downstream, from rework to workarounds, overtime, RFIs, litigation and more. The Get It Right Institute estimates that avoidable errors can amount to 20% or more of the total costs of construction, with direct costs accounting for 5% of the total project value and other factors, such as unrecorded process waste (6%), indirect costs (7%) and latent defects (3%), adding to total waste. Errors also quickly add time to project schedules—up to 52% of total project delays. [Read our earlier blog for a deep dive into the costs of rework.]
Today’s construction projects have become increasingly complex, which increases the potential for error. Quality control and error management are now a critical part of general contractors’ day-to-day role; on any given jobsite, there are a wide variety of things that can potentially go wrong during installation across the building’s structure, shell and interiors, including:
Misplaced elements (e.g., embeds in the wrong place or orientation).
Omitted elements (e.g., an embed was mistakenly not installed).
Design coordination errors (e.g., a riser that clashes with the wall framing location).
Installation of unspecified materials (e.g., wrong waterproofing membrane material).
Damaged or defective installed elements (e.g., cracked glazing panel).
Incomplete installation (e.g., missing weep holes).
Installation of components that are the wrong size (e.g., a mechanical curb or block out opening that’s too large or too small).
Mistaken layouts (e.g., control points in wrong location).
Incorrectly coordinated adjoining materials (e.g., walls, studs and frames of an opening not conforming to the opening size).
With tens of thousands of elements being installed across a project and multiple trades working simultaneously, understanding—and solving—the root causes of rework can be a game-changer for general contractors and developers alike.
Common causes of rework
The most common causes of rework on large commercial construction projects fall into a few main categories:
Drawings aren’t up to date. Design is always evolving; sometimes, installers are working off of old shop drawings. In other cases, sub trades are working off their own drawings, rather than design plans issued by an engineer or architect, and errors can happen between design intent and the layout document.
Drawings are up to date, but the installer makes a mistake. Even when drawings are up to date and accurately reflect the design intent, errors can occur during installation—people, after all, aren’t infallible.
Manual quality control (QC) methods rarely provide 100% verification; spot checking is common. Without digital construction verification, it can be hard to do a complete verification at speed so projects stay on schedule.
There’s a lack of coordination between trades; disciplines fail to coordinate where things need to be. One study found a lack of working procedures and clear lines of communication to be a “key predictor” of rework, and another estimates that poor project information and poor communication among stakeholders is to blame for nearly half of all rework.
Installation layout equipment is calibrated incorrectly. For example, a mistake in the mix for concrete panels for a nearly $6 billion metro line project resulted in federal and state lawsuits against a manufacturer after inspectors discovered that the manufacturer had not properly calibrated new equipment—a misstep that was likely to cause of the error, they found.
The industry can potentially do a lot of great things with technology to coordinate and do clash detection, such as with Building Information Modeling (BIM) software. But whether design plans are produced in CAD or BIM, the key challenge remains: How do builders ensure that fieldwork is completed according to plan? In other words, how can you connect digital plans directly to the built world?
A new toolset available today goes beyond providing digital pictures to provide automatically generated element-level insights into the conformance of fieldwork to plans as work is in progress. With Digital Construction Verification (DCV), you can stop managing errors and start preventing them by catching errors in the moment:
During pre-pour: Verify all structural elements and MEPF.
During installation: Verify all façade layers and workmanship.
During layout: Verify all interior clearances, layouts and rough-ins.
In the next blog in this series, we’ll go into more detail about the impact of rework on the building’s structure.