How to Prompt the AI Estimating Assistant for Better, More Accurate Bids

Getting a high-quality estimate from the AI starts with a high-quality prompt. The more clearly you define the project scope, assumptions, and desired output, the less the AI has to guess—and the more accurate and useful your bid will be.

In this guide, we’ll walk through the fundamentals of prompting the AI, using real construction examples. You’ll learn what information matters most, how to structure your prompts, and how small clarifications can dramatically improve results.

Video Walkthrough: Prompting Basics

 

Step-by-Step Guide to Better AI Prompts

Start With the Right Mindset

Think of the AI like a junior estimator. It can move extremely fast, but it only knows what you tell it (or what it can clearly infer). Your goal is to eliminate ambiguity and reduce assumptions wherever possible. Whenever you can, upload a planset. This gives the AI a concrete reference for quantities, assemblies, and scope—and dramatically improves accuracy.

 

Tip #1: Define Dimensions, Rooms, and Layout

Always start with the physical basics of the project. These details anchor the entire estimate as they directly impact aspects like framing, drywall, painting, finishes, MEP scope, and labor hours.

Include:

• Overall square footage

• Building footprint

• Room count and room sizes

• Ceiling heights and roof type

Example:

• 672 SF detached ADU

• 42’ x 16’ footprint

• 2:12 shed roof

• 8’ vaulted ceilings throughout

• 1 bedroom (118 SF)

• 1 bathroom (74 SF)

 

Tip #2: Specify Finishes and Schedules (or Allowances)

Finishes are one of the biggest cost drivers, and one of the easiest places for ambiguity to creep in.

Examples:

• Class A asphalt shingles

• James Hardie shiplap siding or equivalent

• Marvin aluminum windows and doors or equivalent

• Luxury vinyl plank flooring at $4/SF

• Porcelain tile bathroom flooring at $5/SF

• Kohler plumbing fixtures or equivalent

• 16 Lutron recessed lights

• Custom veneer cabinetry, approximately 40 SF

 

Tip #3: Confirm Site Work, Demolition, and Utilities

Site conditions and utilities often account for major cost swings. If they’re not explicitly defined, the AI has no choice but to assume.

Call out items like:

• Demolition scope

• Utility upgrades

• Trenching distances

• Foundation details

Example:

• Demolish six 6’ x 12’ garden boxes, includes safe off-haul of all spoils

• Raised perimeter foundation with four 12” x 12” spread footings

• Upgrade electrical service from 200A to 400A

• Assume 150 LF trenching per utility run

• Include sump pump

 

Tip #4: Define Inclusions and Exclusions Clearly

This is one of the most important—and most overlooked—steps. Be explicit about what is and is not included so the AI doesn’t waste time estimating irrelevant scopes.

General Contractor Example

Initial prompt:

Create a bid for this project.

Improved prompt:

Create a bid for the general contracting scope of this project. Exclude landscaping, security systems, permitting fees, and appliances.

Trade Contractor Example

Initial prompt:

Bid the drywall scope.

Improved prompt:

Only bid the drywall scope. Do not include baseboard, trim, or painting.

 

Tip #5: Outline Assumptions to Eliminate Guesswork

If something isn’t shown clearly on the plans, tell the AI what to assume, as this prevents the AI from filling in gaps incorrectly.

GC Examples:

• “Assume a 4” slab-on-grade foundation.”

• “Assume Class A asphalt shingles.”

Trade Examples:

• “Assume Type X drywall at all exterior walls.”

• “Assume Level 5 smooth wall finish throughout.”

 

Tip #7: Clarify Your Ideal Output Format

Finally, tell the AI how you want the estimate structured. This ensures the final bid aligns with how you typically present pricing to clients or reviewers.

Examples:

• “Break out labor and materials as separate line items.”

• “List required grading scope under exclusions if shown on plans.”