Vertical integration: bringing an upstream step inside the fence

Two businesses under one roof

The stage you absorbed rarely resembles the one you already ran. A moulding shop feeding an assembly plant works to different cycle times, a different maintenance regime and a different labour profile; a foundry feeding a machine shop runs to melt schedules that ignore the assembly calendar entirely. Management attention divides, and the smaller or less familiar stage usually loses. The commitment worth naming explicitly is technical: somebody has to keep the upstream process current, which means retaining specialists in a discipline that is no longer the company's main trade.

Stage capacities never match

Upstream equipment arrives in its own increments — a furnace, an extruder, a coating line — and those increments almost never divide neatly into downstream demand. The result is a stage that is either a bottleneck or under-loaded, and both are expensive. Buffer stock accumulates between the stages to decouple them, reintroducing exactly the inventory integration was often meant to remove. Selling upstream surplus externally solves the loading problem and creates a new one: outside customers with delivery expectations who compete with your own assembly line for the same capacity.

Transfer pricing decides who looks profitable

Once the stage sits inside, the price at which output moves between them is an accounting choice, and it determines which part of the business appears to earn money. Pricing at cost hides the upstream stage's efficiency; pricing at market keeps it honest but needs a market reference that may not exist for a bespoke intermediate. Either way, purchasing loses a benchmark it used to receive free with every quotation, so occasional external tendering — even with no intention of switching — becomes the only reliable way to know whether the internal stage is competitive.

Fewer handovers, and fewer excuses

Integration genuinely improves control of the intermediate specification: an upstream parameter can be changed to fix a downstream problem without negotiation, and traceability from raw material to finished product runs through one system. What it also removes is the discipline of an external quality agreement. Internal non-conformances get settled by conversation rather than by concession note, marginal material gets accepted because rejecting it idles a sister department, and the failure record thins out. Keeping formal acceptance criteria between internal stages is unpopular and worth insisting on. Recording internal rejections with the rigour applied to a supplier also preserves the evidence needed later to judge whether the stage is really performing.

Capital, obsolescence and the difficulty of leaving

The upstream stage carries its own investment programme, competing for funds with the business you understand better. Technology in that field moves whether or not you follow it, so an integrated stage can quietly fall a generation behind while a specialist supplier reinvests. Exit is harder than entry — closing a stage means writing off assets, losing the people and re-qualifying an outside source that has meanwhile lost interest. Systems must carry multi-level bills of materials, internal orders between stages, and costing that shows each stage's contribution rather than one blended figure.

Frequently asked questions

How should we price material moving between our own stages?

Pick a basis and hold it long enough to learn something from it. Standard cost plus an agreed margin keeps behaviour stable but says little about competitiveness; market price, where a genuine reference exists, gives sharper signals and generates arguments about which quotation counts. Whatever the basis, review it on a fixed cycle and test it occasionally against outside quotations, since the purpose of the exercise is information rather than internal fairness.

Should an in-house stage be allowed to sell to outside customers?

It is often the only way to load the asset properly, but set the rules before the first external order. Decide who takes priority when capacity is short, how internal demand is committed and by when, and whether outside work can be refused without penalty. Consider disclosure as well: an external customer may compete with your downstream business, and process knowledge travels alongside the product you ship them.

What warning signs suggest an integrated stage is no longer worth keeping?

Persistent quality problems that would be unacceptable from a supplier, capital requests arriving without any competitive comparison, an inability to recruit people with the relevant skills, and outside quotations that keep landing below internal cost even after overhead is adjusted honestly. Any one of these can be temporary. Appearing together, they usually mean the stage has stopped being a capability and become a habit.