Most offsite bids lose on the first spreadsheet. A purchasing manager lines up a quote for wall panels and trusses against the lumber takeoff for the same plan, sees a higher number, and the conversation ends there. It measures only one line of a longer cost story.
A fair comparison asks a different question. What does it cost to get the structure framed, inspected, dried in, and ready for the next trade, including every delay and correction? That is total cost of ownership, and it is the only basis on which offsite and site framing can be judged side by side.
Why the sticker price misleads
A component quote bundles costs that a lumber package leaves out. The factory price usually includes engineering, layout, cutting, assembly labor, and some of the waste that would otherwise end up in a site dumpster. The lumber package includes none of that. It is a list of materials, and the labor, supervision, and rework needed to turn it into a frame sit in other budget lines, often owned by other people.
Taylor Morrison’s Austin division offers a useful reference point. As reported by Tyler Williams in HousingWire, the builder found that components carried a sticker premium of roughly 16.1 percent over stick framing, and that the gap shrank to about 0.7 percent once total cost of ownership was counted. The exact figures belong to that builder and that market. The lesson travels well: the headline premium and the real premium can be very different numbers.
What to put in the model
Build the comparison per house or per unit, using your own job cost history where you have it. The categories that tend to move the answer are these:
- Framing labor, including the crew hours for layout, cutting, and assembly that the factory absorbs.
- Material waste, theft, and weather damage on site.
- Cycle time, expressed as days from foundation to dry-in, and what each day costs in carrying, supervision, and overhead.
- Rework and callbacks traced to framing errors, such as out-of-square walls or missed blocking.
- Dumpster pulls and site cleanup.
- Crane or equipment rental and delivery logistics on the offsite side.
- Engineering and plan review costs that shift from field to factory.
Soft costs such as cycle time need a daily rate agreed in advance by finance and operations. Agree the rates before you run the numbers, not after, or the model will drift toward whatever answer someone wanted.
Common failure modes
The most frequent mistake is counting offsite costs in full while counting site costs at their best case. A framing crew that never makes errors and never waits on weather does not exist, so do not model one.
The second mistake is ignoring who carries the risk. When a factory commits to a delivery date and a dimensional tolerance, part of the schedule and quality risk moves off the builder’s books. That shift has value even when it does not show up as a line item.
The third is judging the whole idea on one pilot house. Early units carry learning costs for everyone involved. Evaluate the program over a phase or a full community, and track the same metrics on a stick-framed control group built at the same time.
Making the decision
When the model is complete, the decision gets simpler. If the all-in difference is small and offsite reduces schedule variance, components are usually the better business choice, because predictable cycle time compounds across every home in the pipeline. If the gap stays wide after honest accounting, the answer may be a narrower scope, such as trusses only, rather than abandoning offsite construction altogether.
#TotalCostOfOwnership #OffsiteConstruction #StickFraming #WallPanels #Trusses #CycleTime
Source: Taylor Morrison Austin component cost figures as reported by Tyler Williams, HousingWire (https://www.housingwire.com/articles/taylor-morrison-austin-offsite-components/).
Image: National Institute for Occupational Safety and Health (NIOSH), Wikimedia Commons