What happens if the design changes after fabrication has begun?
Every construction project has changes. The difference in modular is when they can happen without cost, and that window closes earlier.
What happens if the design changes after fabrication has begun?
A module in production is being built to fixed dimensions, so a change affects manufactured work rather than work still to be done. Changes are therefore resolved during the design stages, before fabrication, which is why the design has to be genuinely closed rather than closed enough to start.
This is the fair objection to modular construction and it deserves a direct answer rather than a reassurance.
Yes, changing a design after fabrication has started is more disruptive than changing one on a conventional site. That is a real property of the method.
Why it is different
On a conventional site, construction is sequential. At any point, a large proportion of the work has not been done yet, so a change lands on work still ahead rather than on work already built.
In volumetric modular, the building is being manufactured to fixed dimensions in parallel with the site works. A change to a module in production affects something already made.
You cannot move a wall in a module that has been framed, serviced and lined, in the way you can move a wall on a site before the trades reach it.
What that constraint actually produces
It forces decisions forward.
The eight design stages exist for this reason. Each closes a set of decisions before the next begins, and by the end every dimension a module will be built to is fixed, every service penetration is located, and every compliance provision is documented rather than intended.
That is more work at the front and it is why the programme holds afterwards. A conventional project defers decisions and pays for them later as variations. A modular project cannot defer them, so it does not pay for them later.
Decisions made early are cheaper than the same decisions made late. The method makes that structural rather than optional.
Where change is still straightforward
Not everything is locked when fabrication begins.
**Finishes and fixtures** in many cases, depending on the stage and the item.
**Site works.** Landscaping, external works, driveways and paths are conventional construction and change like conventional construction.
**Anything not yet in production.** On a multi-dwelling project, modules are built in sequence, so a change can apply from a given point forward.
**Loose items and fitout** that are installed after delivery.
The honest position is that the closer something is to the structure and the services, the earlier it has to be settled.
Where it becomes expensive
Structural dimensions. Service positions. Anything that changes the module envelope or how it meets the foundation.
These affect a manufactured object and, on a multi-dwelling project, a manufactured sequence.
How it is managed
The same way any change is managed: identify it, price the effect on cost and programme, obtain an instruction, then proceed. Never the other way around.
What differs is the honesty required at the design stages. A stage that closes with an open question has not closed, and the deferred question reappears at the point where it costs the most.
That is why the client involvement is concentrated early. It is not a preference, it is the mechanic that makes the rest of the programme work.
The trade the client is actually making
More attention in the first phase, in exchange for a programme that does not stop to ask questions and a cost that does not drift.
For a provider committing to residents on a date, or a financier holding a site, that is usually the better side of the trade. A programme that holds is worth more than the ability to change your mind in month seven.
See how the design stages run or talk to us about your project.
MADEmodular / MADEbetter.
MADEmodular / MADEbetter.