Why “As-Built” Substation Drawings Often Don’t Match Construction Drawings And How Keentel Engineering Prevents It

Introduction: The Hidden Cost of Drawing Mismatches

In substation projects, one of the most costly and frustrating issues occurs when as-built drawings barely resemble the issued-for-construction (IFC) drawings.

When this happens, it typically leads to:

• Budget overruns
• Project delays
• Construction rework
• Procurement conflicts
• Engineering redesign
• Operational confusion



At Keentel Engineering, we specialize in eliminating these risks by integrating constructability, QA/QC, procurement alignment, and field expertise into every substation design project.

Why Do As-Built Drawings Differ from Construction Drawings?

Through decades of industry experience, three primary causes consistently emerge:

1. Failure to verify existing site conditions
2. Designing without understanding construction practices
3. Weak or rushed QA/QC processes

Let’s examine each and how Keentel Engineering addresses them.

1. When Drawings Don’t Match the Real World

One of the most common causes of field changes is the discrepancy between design drawings and actual site conditions especially in brownfield substations.

Typical Issues Include:

• Outdated record drawings
• Underground congestion not documented
• Equipment removals or additions not reflected
• Previous field markups never incorporated

Keentel Engineering’s Approach:

We prevent these issues by requiring:

• Mandatory site walkdowns before major design phases
• Physical verification of equipment and clearances
• Soil resistivity testing for grounding design
• Foundation condition assessments
• Grounding system testing
• Cross-checking legacy drawings against real conditions

We design based on reality not assumptions.

2. Theory vs. Practice: Designing Without Constructability

Engineering theory alone does not guarantee constructability.



For example:

• A 3-conductor 500 kcmil cable may look efficient on paper, but can be extremely difficult to pull, splice, and terminate.
• Replacing transformers may appear simple until operational constraints, temporary phasing, and space limitations are considered.

Designers without field experience often overlook:

• Cable pulling tensions
• Conduit bend radii
• Equipment access for cranes
• Maintenance clearance
• Temporary transformer placement
• Real estate constraints in energized yards
  

Keentel’s Constructability Integration

At Keentel Engineering, we:

• Involve construction professionals early
• Model phasing sequences
• Validate access routes and lifting plans
• Check conduit fill and cable pulling feasibility
• Evaluate staging areas
• Ensure maintainability is designed in

Constructability is engineered into the design not discovered in the field.

3. Poor Drawing Quality

Field markups often stem from poor drawing quality, including:

• Inconsistent labeling (e.g., GCB vs BKR references)
• Copy-paste errors
• Inconsistent foundation details
• Missing material callouts
• Overcrowded or unclear drawings
• Incorrect material specifications



Drawings are construction instructions. If instructions are unclear, construction slows down.

Keentel Engineering’s QA/QC Framework

A strong Quality Assurance / Quality Control program reduces total project cost by preventing field errors before construction begins.

Quality Control (QC)

• 100% detailed drawing review
• Cross-discipline checks
• Material schedule verification
• Conduit and cable tray capacity checks
• Protection and control consistency review
  

Quality Assurance (QA)

• Senior engineer oversight
• Constructability validation
• Owner standard compliance
• Review milestone enforcement

Our QA/QC system ensures drawings are:

• Precise
• Consistent
• Complete
• Buildable



This dramatically reduces RFIs and field markups.

The Critical Role of Scheduling

Aggressive project schedules often compromise quality.



When engineering timelines are compressed:

• Vendor drawings arrive late
• QA/QC gets rushed
• Procurement decisions are delayed
• Critical path coordination fails
  

Keentel’s Scheduling Methodology

We integrate:

• Engineering fact-finding phase
• Early engineering decision deadlines
• Milestone reviews (30% / 90%)
• Procurement alignment
• Critical path coordination
• Vendor drawing tracking

Large transformers, steel structures, and control panels often have long lead times. Engineering must align with procurement not react to it.

The 30% and 90% Review Milestones

30% Review – Early Design Validation

Includes:

• Single-line diagram
• Yard general arrangement
• Foundation concepts
• Elevation views

At this stage:



• Layout is validated
• Constructability is reviewed
• Major procurement decisions are authorized

Changes after this point are expensive and disruptive.

90% Review – Final Pre-Construction Validation

This is the final opportunity to verify:



• Conduit routing
• Bus detailing
• Wiring diagrams
• Foundation details
• Protection schematics

Construction teams review drawings as if they are building from them.

Keentel ensures this milestone is never rushed.

Procurement Integration: Avoiding Field Delays

Modern manufacturing requires long lead times.

If procurement is not synchronized with engineering:

• Materials arrive late
• Foundation designs stall
• Construction pauses
• Costs escalate

Keentel Engineering:

• Tracks vendor drawing submissions
• Verifies material conformity
• Ensures all materials shown are clearly specified
• Aligns procurement milestones with engineering releases

No assumptions. No missing parts. No surprises.

Post-Project Review: Continuous Improvement

After project completion, Keentel conducts:

• Field markup analysis
• Root cause evaluations
• Lessons-learned workshops
• Process updates



This feedback loop strengthens future projects.

The Importance of Team Selection

Successful substation projects require team members with:

• Construction experience
• Mechanical aptitude
• Organizational skills
• Strong communication ability

Communication is not just talking it’s listening across engineering, procurement, construction and operations.

Keentel Engineering builds multidisciplinary teams that collaborate from project start to commissioning.

The Three Pillars of Substation Project Success

Every successful substation project rests on:

1. Experience

Understanding both engineering theory and field reality.

2. Quality

Delivering consistent, accurate, and complete drawings.

3. Communication

Aligning engineering, procurement, and construction continuously.



Keentel Engineering integrates all three into every project.

20 Frequently Asked Questions (FAQs)