When MEP design fails in the field: Solving the disconnect between paper and reality

“It looked perfect in the model until someone tried to install it.”

This phrase has been heard too many times across construction trailers, coordination calls, and jobsite walk-throughs. It’s the result of a critical but common pain point in our industry:

MEP systems that are technically sound but practically unbuildable.

It’s the duct run that interferes with the main beam. The panelboard installed behind a door swing. The 16 inch pipe designed to run through a 12 inch shaft. The air handling unit placed in a location where no human can actually service it.

To the architect, civil/structural engineer, and general contractor, this isn’t just an inconvenience. It’s a disruption one that sets off a chain reaction of redesigns, field delays, frustrated trades, and added cost.

At Ardebili Engineering, we believe this isn’t just a coordination issue it’s a design philosophy problem. And fixing it means rethinking how MEP is approached from day one.

The hidden cost of unbuildable design

Unbuildable MEP designs cost more than just money. They fracture trust. They delay schedules. And they create avoidable conflict between disciplines.

Here’s what it looks like across the team:

🔷 For architects

• Your finished ceilings are lowered last-minute due to duct rerouting.

• Carefully designed soffits are added post-coordination to hide piping conflicts.

• Your design intent is compromised because MEP systems weren’t integrated early enough.

• You’re fielding complaints from the client about “why it wasn’t coordinated.”

🔷 For civil and structural engineers

• Emergency requests for beam penetrations, truss notching, or slab cores become the norm.

• Structural integrity is questioned due to last minute reroutes of heavy MEP systems.

• Your design is adjusted to fit systems that should’ve worked within your constraints not the other way around.

🔷 For general contractors

• Your trades are spending time solving design issues in the field.

• You’re issuing RFIs not to clarify intent, but to fix coordination breakdowns.

• Labor is wasted, sequencing is affected, and prefab schedules are compromised.

• You’re left managing the fallout with owners and stakeholders.

The takeaway? When constructability is ignored during design, the burden falls on those who can least afford the disruption the teams executing in the field.

How these issues slip through

Despite the rise of BIM, clash detection, and advanced modeling, constructability issues still make it to site. Why? Because tools can’t replace judgment and real world experience matters more than ever.

Here are the most common causes:

1. Design decisions made in isolation

Engineers often optimize for code compliance, pressure drops, voltage drop, or air distribution but not for installability. The design might “fit” within the space virtually, but ignore support, clearances, or sequencing.

2. Overreliance on software coordination

Clash detection tools tell you when systems collide. But they don’t tell you when a pipe is routed in a way that can’t be sloped, or when two trades need the same working space at the same time.

3. Lack of field experience among designers

If your team hasn’t stood in a mechanical room, watched ductwork be installed, or tried to swing a wrench in a tight chase, you’re missing the context to design buildable systems.

4. Compressed design schedules

As deadlines shrink, teams are forced to rush coordination, reuse details, and approve layouts before reviewing constructability. This often pushes design problems downstream where they’re more expensive to fix.

Real world examples of unbuildable design

Let’s get specific. Here are real world issues we’ve helped solve (or prevented altogether):

• Riser misalignment: A plumbing riser was intended to run through stacked restrooms, but minor shifts in shaft wall placement between floors weren’t accounted for. This led to major layout adjustments and structural coordination challenges during installation.

• Inaccessible AHU: An air handling unit was placed above a corridor ceiling without any consideration for access. During field review, it became clear that maintenance tasks like filter replacement or coil servicing couldn’t be performed without altering finished construction.

• Oversized ducts in tight framing: A large supply duct was routed through a truss space with no room for insulation, structural clearance, or hanger placement. Although it fit in the model, it failed inspection and had to be reengineered on site.

• Panels behind doors: An electrical panel was located behind a door swing in a tight utility closet. This violated code clearance requirements and forced a complete re-coordination of electrical, framing, and architectural elements late in the process.
  

These issues weren’t caused by lack of intelligence — they were caused by a lack of field perspective.

Our response: Design for buildability, not just performance

At Ardebili Engineering, we bring constructability into every phase from concept to construction administration. We don’t believe MEP design is complete unless it can be built safely, efficiently, and without compromise.

Here’s how we make it happen:

🧠 1. We design with field logic, not just code compliance

We don’t just ask if a system meets code. We ask:

• Can this system be installed with a lift or boom?

• Is there enough room for a ladder, swing clearance, and tool access?

• Can this be maintained or replaced without tearing out finished construction?

• Will this create issues during commissioning or inspection?

Every system is reviewed not just for technical performance, but also for installability and maintainability.

📐 2. We coordinate holistically before clash detection

We don’t wait for models to tell us there’s a problem. We coordinate proactively:

• We confirm shaft sizes and align them across floors.

• We work with structural teams to route systems between beams not through them.

• We align with architectural ceiling types and lighting layouts from day one.

• We request early input from GCs on install sequencing and prefab needs.

This approach dramatically reduces field friction and eliminates the domino effect of late stage fixes.

🦺 3. Our engineers know the field

Our team has walked mechanical rooms, participated in commissioning, and observed how trades build under pressure. That experience is invaluable because constructability can’t be modeled, only understood.

We encourage jobsite visits, post project feedback sessions, and engineer-field collaboration that improves future designs.

🧩 4. We design in sync with construction sequence

Designs that ignore construction phasing create major install conflicts. That’s why we ask:

• Is this system scheduled to go in before walls go up?

• Will steel or structure be blocking this route by the time MEP gets there?

• Does the routing logic support prefab and installation windows?

• What’s the tolerance on routing accuracy, and is it realistic?

When we know your build sequence, we can optimize our designs to support it — not disrupt it.

What happens when you get it right

When constructability is embedded in design, everyone wins.

✅ Fewer RFIs and Change OrdersNo need for field engineers to solve design issues with workarounds or redesigns.

✅ Streamlined InstallationTrades move confidently, with prefabricated assemblies and fewer schedule impacts.

✅ Cleaner CloseoutNo maintenance access issues. No fire/life safety violations. No rework during inspection.

✅ Better Client OutcomesOwners don’t just get systems that work they get systems that are accessible, durable, and lower maintenance.

✅ Stronger RelationshipsArchitects, GCs, engineers, and field teams work as a unified team not in silos.

A message to our partners

If you’ve ever been burned by late stage MEP issues, you know how frustrating it can be. But it doesn’t have to be that way.

At Ardebili Engineering, we pride ourselves on being more than just a consultant we’re a collaborator. One who listens, understands your sequencing needs, respects your design intent, and engineers with the field in mind.

We don’t believe in “good enough” models. We believe in buildable systems. Systems that reduce risk, protect your budget, and support every phase from concept to commissioning.

Let’s build better together!

If your team is dealing with constructability challenges, or if you’ve had to redesign systems after drawings were stamped, let’s talk. We’ll walk your project like it’s being installed tomorrow and design it like we’ll be the ones building it.