One question I hear from nearly every homeowner is:
“How much will it cost to build my house?”
It sounds simple, but the answer depends on how prepared you are. Builders aren’t trying to be vague on purpose—pricing a custom home is impossible without clear information. In this post, I’ll explain what documents, decisions, and planning you need before asking for a reliable estimate.
Many homeowners approach a contractor with something like:
“I want to build a 3-bedroom modern house with high ceilings—how much will it cost?”
But that one sentence doesn’t give nearly enough information to define the scope of work. Without detailed plans or decisions, you’re likely to get one of three responses:
To get a reliable number, you need four critical pieces of information—outlined in professional contracts used across the construction industry.
We use the AIA’s General Conditions document as a reference. AIA stands for the American Institute of Architects, which creates standardized construction contracts based on decades of legal and field experience. You can purchase their contract documents here:
👉 https://shop.aiacontracts.com/
According to AIA standards, a complete construction scope includes:
This defines what the contractor and their subcontractors are responsible for, including labor, equipment, and materials.
These are the architectural plans that show the layout, elevations, sections, dimensions, and details.Typical plan set includes: site plan, floor plan, elevations, wall sections, and interior details.
Written instructions for the materials and systems to be used.
For example:
These decisions directly impact pricing and scheduling.
All visual and conceptual materials prepared by the architect or designer to explain the intent of the building—renderings, 3D models, sketches, notes, etc.
Building in 3D is a visual language. Plans alone may not capture everything, especially in custom designs with complex geometry.
When you go out for bidding, the level of detail you provide determines how accurate the quotes will be.
Example:
A client provides full plans, specs, and design intent for a 2,500 sq ft home. One contractor prices it at $275/sq ft. Another offers $285. The numbers are close.
Another client only gives a mood board and says, “Something modern with vaulted ceilings.” The estimates range from $250–$450/sq ft.
The more decisions you make upfront, the fewer surprises you’ll face later.
Even if you buy pre-designed plans, we always recommend working with a local architect. Here’s why:
Not every product decision is made up front—some things (like lighting, appliances, or tile) are selected late in the project.
Allowances are placeholder dollar values written into the contractor’s bid. For example:
Make sure these values align with your expectations—or you’ll face upcharges later.
Most residential builders give rough timeframes like “12 months” or “18 months,” but delays happen—especially when projects lack clear scheduling.
The AIA contract format includes a requirement for:
Even for residential jobs, this structure helps clients track progress and identify issues early.
This isn’t just for homeowners—AIA-style contracts benefit contractors as well. They:
AIA contracts include a waiver of consequential damages. This protects the builder if, for example, a vacation rental is delayed and misses the peak season. The contractor isn’t liable for lost profits.
There’s a famous case where a casino opened late and tried to sue the builder for missed revenue. The court upheld the waiver in the contract.
Getting a construction estimate isn’t just about square footage or style.
It’s about preparation.
If you want a real number—and a smooth build—come to your contractor with:
Want to go deeper?
Check out the AIA residential contract templates here:
👉 https://shop.aiacontracts.com/contract-documents/6406765-owner-contractor-custom-residential
What it is
AIA Document A110–2021 is a stand-alone agreement with its own internal general conditions and is intended for use on custom residential construction projects. A110 may be used for custom residential projects where payment is based on either a stipulated sum or the cost of the work plus a fee, with or without a guaranteed maximum price. Parties using AIA Document A110–2021 will also use A110 Exhibit A, Determination of the Cost of the Work, if using a cost-plus payment method.
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