Key Takeaways:
- The average time to build a house is now 8.8 months, 1.6 months longer than in 2015.
- A typical site-built home depends on a sequence of nearly 30 different subcontractors.
- Almost none of these trades can start before the one before it finishes and passes inspection.
- It takes 15 months just to move from applying for zoning approval to the start of site work.
- None of these pieces, contractors, or approvals, coordinate with each other.
Most people assume that the long wait on site-built homes is due to construction alone. The framing, the roofing, the finish work.
In reality, a lot of that time has nothing to do with how fast any single trade can move. Construction delays come from how many separate businesses must pass a project between them, one at a time.
According to the National Association of Home Builders (NAHB), the average single-family home building process now takes 8.8 months, 1.6 months longer than in 2015.
In this blog, we’ll break down four of the biggest bottlenecks driving the average time to build a house: the number of contractors involved, the construction sequence they have to work in, zoning and jurisdiction approval, and why none of it moves in coordination.
None of these bottlenecks disappear just because a home is built differently. But a home shouldn’t have to wait on all of them at once.
1. A Site-Built Home Depends on Nearly 30 Separate Contractors
Building a home isn’t one job. It’s a long chain of separate businesses, each with its own crew, its own schedule, and its own licensing requirements.
The average single-family home uses 24 different subcontractors, and 69 percent of builders use somewhere between 11 and 30. That range covers everything from design, architecture, and engineering to excavation and foundation work, to framing.
Every one of those subcontractors must be scheduled, show up on time, and finish their portion before the next trade can even begin.
2. The Sequence Only Moves in One Direction
The reason so many contractors add up to so much time isn’t the number itself. It’s that almost none of them can work at the same time, because the construction only moves in one direction.
This is what construction schedulers call trade sequencing. Electrical work can’t start until framing is complete. That kind of task dependency defines a project’s critical path, the sequence of tasks that control how long the entire job takes.
Any delay on a critical path task pushes the finish date back directly.
3. Skilled Labor Shortages Make Scheduling Harder
Coordinating nearly 30 subcontractors is difficult even when every trade has plenty of workers to pull from. It gets much harder when there is a shortage of skilled labor.
More than 55 percent of single-family builders experienced a shortage of labor across 16 home-building trades, with over 90 percent reporting a shortage of subcontractors specifically in multiple carpentry categories. Framing, rough carpentry, and finish carpentry, three of the trades every home depends on early and often, were among the hardest to staff.
When a trade is short on workers, a builder isn’t just waiting for a crew. They’re waiting for whichever crew happens to be available, on whatever schedule that crew already has.
4. Zoning and Local Jurisdictions Add Another Layer on Top
Contractors and labor shortages aren’t the only things slowing a project down.
Before construction can even start, a project must clear zoning and satisfy whichever authority having jurisdiction (AHJ) governs that site, and neither runs on the contractors’ schedule.
It takes an average of 15.1 months just to move from applying for zoning approval to the start of site work, followed by another 11.5 months before a finished lot is even sold to a builder. That’s more than two years spent clearing approvals before the contractor construction sequence has even started.
Where This Leaves the Industry
None of these four bottlenecks disappear just because a home is built differently.
Factory-built homes address the problem that is solvable: the contractor coordination chain that drives most of a site-built home’s construction timeline.
Homes get engineered and built in a controlled factory setting, where the same trades work the same repeatable sequence every time. Building in a factory setting largely eliminates the weather delays, missing materials, and subcontractor no-shows that stretch out a site-built schedule.
That doesn’t remove zoning or building code compliance. But it does mean a home can already be built and ready to deploy by the time those approvals clear, instead of waiting months to even start construction.
At BoxHouse, we brought design, manufacturing, certification, and permitting under one roof. We’re working with AHJs to get plans preapproved and obtaining statewide certifications, so local offices don’t have to run extensive plan reviews and analysis on every home. Factories fix the build. We’re fixing the approval.
