A concrete subcontractor working on the deck of a high-rise framed the mechanical blockout right on time and seemingly in accordance with the structural design. A prepour digital scan of the deck, however, revealed that the dimensional size of the opening deviated from the mechanical shop drawings—an issue that, if left unresolved, would have a significant impact on the mechanical systems and interior buildout. Armed with this insight, the subcontractor was able to correct the size of the blockout before the deck pour, avoiding costly rework as well as undoubted cascading conflicts with the design team and multiple trades.
Ensuring that a building’s concrete, MEP systems and embeds are correctly coordinated and installed is paramount to successful construction, as-builts and cost-efficient building maintenance over the long term. When the structure and systems are built accurately and according to plans, construction of the rest of the building goes according to schedule. When errors in installation go undetected, they have a compounding effect, impacting the overall performance of the structure, MEP systems, facade and interior walls.
When issues in the buildout of the concrete and MEP systems are found early in the process, the impacted trades can efficiently correct the mistakes and install as coordinated. They know where exactly on the deck they need to correct the installation of elements according to plans and within project tolerances. Doing so before concrete is poured avoids the need for rework, reduces the number of trades needed to fix the errors and enables trades to make these corrections in the proper sequence when the cost to do so is minimal and the schedule impact inconsequential. In addition, generating a digital record of the installation work performed serves as a guide for future GC, trade and owner modifications.
If, on the other hand, an error isn’t discovered until later by a different trade, this discovery can lead to delay claims, the need to modify materials on site to fit or having to rework the issue entirely. All change orders of this type are typically ones the contractor or subcontractor must fund out of their own budgets. These rework situations can also create tensions that lead to more “intangible” losses: a decrease in worker morale, damage to a brand’s reputation and exposure to accidents and liability.
Errors and rework in the building’s concrete and MEP systems are commonly found in a few areas:
Blockouts and openings
PT tendons and rebar
Embeds for the envelope and other trades
How DCV for the Building’s Structure Can Help
SiteAware’s Digital Construction Verification (DCV) platform for building decks helps ensure that construction errors in the building’s structure are caught early, avoiding costly rework, project delays and frustration later. The platform automatically generates element-level, dimensional, quantity and visual observations for construction teams to verify all structural elements and MEPF in real time before concrete is poured. DCV generates high-resolution visual and narrated reports of every pour and delivers actionable intelligence in real time so errors can be corrected before they can impact schedule and cost.
In the next blog in this series, we’ll take a look at the impact of rework on the building’s façade.