Most capacity decisions are presented as a binary. Take colocation and rent a finished product, or build your own facility and own everything from the land up. A large share of the capacity actually being delivered for AI and high-density workloads sits between the two, and it is the option tenants most often fail to price.
In a powered shell, a landlord delivers a building with utility power brought to it, the core infrastructure that serves the whole site, and connectivity. The tenant takes the empty hall and builds the inside: the electrical distribution, the cooling that serves their white space, the containment, the racks. Build-to-suit is the same idea with the developer taking the design further to a specification the tenant sets, usually against a long lease signed before construction completes.
The attraction is straightforward. You get control over the inside of the facility without funding the land, the structure or the grid connection, and you get it on a programme that someone else is managing. The risk is equally straightforward, and it lives almost entirely at the demarcation point.
What the landlord typically delivers
There is no universal standard, which is exactly why the schedule matters more than the label. In most powered shell deals the landlord provides the land and structure, a weather-tight building with the floor loading and clear heights a data hall needs, utility power brought to the site and terminated at an agreed point, site-wide services such as fire protection to the base building, security to the perimeter, and carrier entry with diverse paths into a meet-me room.
What "power to the site" means is the single most consequential line in the document. Power at the property boundary, power at a transformer you still have to buy, and power at an energised switchboard inside your hall are three very different deliverables with very different costs and dates. The same applies to the cooling plant: a site with a central plant and a capped allocation per hall is a different proposition from one where the tenant provides everything from the chillers down.
What the tenant takes on
Everything from the demarcation inward, which generally means the electrical distribution within the hall, the UPS and any tenant-side generation, the cooling within the demise and the connection to any central plant, containment, busway and distribution, structured cabling, monitoring, and the commissioning that proves it all works together.
That is a construction project with a design team, a contractor, a procurement programme and an integrated testing phase at the end. It is entirely manageable, and organisations that have done it before do it well. It is a meaningful undertaking for an organisation that has not, and it is not well suited to being run alongside a demanding deployment schedule by a team doing it for the first time.
Why the model exists
Powered shell solves a specific problem: a tenant wants control over the inside and does not want to fund or wait for the outside.
Control matters more at high density than it used to. A hall built around direct liquid cooling, a particular rack-scale architecture or an unusual electrical topology is hard to find as a finished colocation product, and a tenant with a strong view on how the inside should work often cannot buy that view off the shelf. Building it inside someone else's shell is faster and cheaper than building the shell as well.
The capital question is the other half, and it is covered in more depth in how data center capacity gets financed. In short, the landlord funds the long-life, easily financed part of the asset, and the tenant funds the shorter-life, highly specific part. Each side is carrying the capital it is better placed to carry, which is why the model survives.
Where the risk actually sits
The power date. The date the landlord commits to energisation is the date your entire programme is built on, and in this region it is a function of the utility and the approvals sequence rather than of the developer's good intentions. The approvals chain to energisation and the realities of interconnection queues are what decide it. Ask what stage the connection has actually reached and what evidence exists, rather than what the programme says.
Long-lead equipment. Tenant-side transformers, switchgear and UPS are on manufacturing lead times that frequently exceed the fit-out programme, which means procurement has to start before a design is fully settled. The constraint is described in transformer and switchgear lead times, and it is the most common cause of a fit-out finishing late.
Interface gaps. The space between the landlord's scope and the tenant's is where programmes fail. Protection coordination across the boundary, who proves the earthing system, whose fire detection talks to whose, who holds the commissioning witness role for shared plant: every one of these has a right answer and none of them has a default answer.
Shared capacity. Where a central plant serves several tenants, your allocation is a contractual quantity rather than a physical certainty. Ask how it is metered, what happens on a plant failure, and what priority applies when total demand exceeds what the plant can deliver.
Lease terms that matter more than the rent
The power commitment. The capacity, the date, the measurement point, and the remedy if it is late. A rent abatement is not a remedy if your equipment is already deployed against a date you were given.
Expansion rights. Whether you have first refusal on adjacent space or additional capacity, for how long, and at what price. High-density tenants outgrow their first hall more often than they expect, and an expansion right agreed at signature is far cheaper than one negotiated from a position of need.
Make-good. What condition the space returns in. A full strip-out of a heavily fitted hall is a substantial liability, and it accrues from day one whether or not it is modelled.
Assignment and sublet. Whether the lease can move with a corporate change, and whether unused capacity can be sublet. Both matter more at the end of a long lease than at the start.
Metering and recharges. How power is measured and billed between landlord and tenant, and how tariff movement passes through. Structures vary by emirate and customer class; our overview of UAE power tariffs explains the shapes these take.
When it is the right answer, and when it is not
It tends to fit organisations that need a specific internal design, have or can hire the engineering capability to deliver a fit-out, have a requirement large enough to justify a dedicated hall, and have a programme with enough slack to absorb a construction schedule.
It tends not to fit requirements that must be live quickly, teams whose scarce engineering attention is better spent on the workload than on a building, requirements small enough that a dedicated hall is inefficient, and situations where the demand forecast is genuinely uncertain. In those cases a colocation product with the sizing risk transferred is usually the better trade, which is the comparison colocation versus building your own sets out, and the reason the standard colocation models exist in the form they do.
How to evaluate a shell offer
Insist on a demarcation schedule rather than a description, line by line, with a named owner against each item. Most disputes in this model are not about quality; they are about something neither party priced because each assumed the other had it.
Test the power date against evidence rather than intent. Ask what the tenant-side capital works out at once the fit-out is designed, not estimated from a rate per square metre. Confirm what the central plant guarantees in writing. Price the whole lease, including make-good and the cost of the fit-out you will not take with you.
Then set that total against a colocation quote for the same capacity over the same period, with the same assumptions about ramp and growth. The comparison is frequently closer than either side expects, and the deciding factor is usually not the money. It is whether you want control of the inside badly enough to take on a construction project to get it.
Frequently Asked Questions
What is the difference between a powered shell and build-to-suit?
A powered shell is a building delivered with utility power and core site services, with the tenant fitting out the inside. Build-to-suit takes the same idea further: the developer builds to a specification the tenant sets, usually against a long lease signed before completion. The practical difference is how much of the design the landlord delivers and how much the tenant does.
Does a powered shell include cooling?
It varies, and the label does not tell you. Some shells include a central cooling plant with a capped allocation per hall; others provide only the space, structure and condenser water or no mechanical plant at all. This is one of the lines that must be read from the demarcation schedule rather than assumed from the term used.
Is a powered shell cheaper than colocation?
Not reliably. The rent is lower because the landlord is delivering less, and the difference reappears as tenant capital, design and construction management, and programme risk. Compared properly over the full term, including fit-out and make-good, the two often land closer together than the headline figures suggest.
What is the most common failure in a powered shell project?
The interface between the landlord's scope and the tenant's. Protection coordination, earthing, fire system integration and commissioning responsibility for shared plant all sit on the boundary, and items that neither party priced because each assumed the other had them are the usual cause of delay and dispute.
How long does a shell fit-out take?
The design and construction can be compressed; procurement of long-lead electrical equipment usually cannot. Transformers, switchgear and UPS frequently sit on manufacturing lead times longer than the construction programme, which means ordering has to begin before the design is fully settled, and that sequence rather than site work is what sets the date.
Weighing a Shell Against Hosting?
Rax Data & Energy can set the same requirement out as colocation, as a powered shell and as a build, with the demarcation and the programme made explicit.
Contact Rax Data & Energy