Common Estimating Mistakes When Using Chief Architect Plans (And How to Avoid Them)

[jamesharden]

Hi everyone,

I’ve been working as a freelance construction estimator for a few years now, and I regularly receive Chief Architect plans from residential builders, remodelers, and design professionals for takeoffs and cost estimates. While the software is very powerful, I’ve noticed some recurring issues that can impact the accuracy of estimates if not addressed early.

Here are a few common estimating mistakes I’ve observed when working with Chief Architect files:

1. Missing Foundation Details
Many times, foundation types or stem walls are not clearly labeled, which causes miscalculations in concrete, rebar, or insulation.

2. Wall Assembly Layers Not Customized
Builders often stick with default wall assemblies in Chief Architect, but in reality, regional code or project specs require changes (like thicker insulation or WRBs).

3. Incomplete Roof Specs
Roof plans sometimes lack proper overhang details or pitch info — leading to errors in material counts like fascia boards and underlayment.

4. Doors & Windows Not Tagged Correctly
Window/door schedules are often not cleaned up, which causes confusion during quantity takeoff or budgeting.

5. No Notes on Finish Levels
This is a big one. Tile vs vinyl flooring, paint vs wainscot, or standard trim vs custom can all swing the cost — especially when left unspecified.

Tip: I usually recommend attaching a quick “Scope Clarification” note to the plan set or a single-page “Spec Sheet” for smoother estimating and fewer RFIs.