Choosing between office fit out companies comes down to three important checks, their project delivery model (Design & Build vs. Traditional), their financial stability relative to your project scale, and their environmental compliance credentials (such as B Corp status).
The best office fit out companies will all align with your ideals. Get these three right and you eliminate most of the risk before a single contract is signed.
This guide walks through each of these checks in turn. For a broader look at the fit-out process itself, from planning through to handover, see our full office fit-out guide.
1. Define your workplace strategy and project brief first
A successful fit-out depends on internal alignment before you approach a single contractor. Fit-out projects that start without a clear brief can drift and become unfocused leading to budgets over running, and mismatched expectations.
Before even inviting contractors to pitch to your company, consider the following:
Your core business goals for the space (growth, culture, client impression, cost efficiency)
Your hybrid working model and how it affects desk ratios, meeting room provision, and collaborative space
Headcount projections for the next three to five years, not just current numbers. Our guide to office space planning covers how to translate headcount growth into an accurate space brief.
Technical requirements, including IT infrastructure, acoustics, and accessibility needs
A well-defined brief also makes it far easier to compare quotes on a like-for-like basis later in the process.
2. Office fit out companies: design & build vs. traditional delivery
Your procurement route dictates your financial exposure and project timeline. Here is how they stack up.
Factor | Design & Build | Traditional |
Single-point responsibility | Yes, one contractor holds design and build responsibility | No, design and construction are managed separately, often by different firms |
Speed | Generally faster, as design and construction can overlap | Generally slower, as design must be completed before tendering construction |
Cost management | Cost is typically fixed earlier, offering more budget certainty | Costs can be refined in more detail before construction begins, but are less fixed upfront |
Risk allocation | Risk sits largely with the contractor | Risk is shared between the client, architect, and contractor |
Design & Build suits clients who want a single point of accountability, a faster programme, and less time spent managing multiple parties. Traditional procurement suits clients who want greater design control, are working with an existing architect they wish to retain, or want design fully resolved before committing to construction costs.
For a fuller breakdown of each route, see our guide to Design & Build vs. Traditional Procurement.
3. Benchmark the fit-out partner's financial stability
Failing to conduct deep financial due diligence is a primary cause of mid-project disruption. As an industry rule of thumb, your project value should represent somewhere between 10% and 25% of the contractor's annual turnover.
The risks sit on both sides of that range. Too large a project relative to turnover, and you risk the contractor's financial stability being tested mid-project, with insolvency a real, if uncommon, possibility. Too small a project relative to turnover, and you become a low priority, with junior staff assigned and senior attention in short supply.
Once you have a realistic budget in mind (see our fit-out cost guide), you can start benchmarking that figure against a contractor's turnover. Request their most recent financial accounts and consider a credit check as standard due diligence. Match the partner's scale to your project's scale, and you remove one of the biggest sources of risk before work even starts.
4. Audit environmental governance and sustainability credentials
Generic "green" claims prove nothing. Demand evidence of environmental management frameworks instead:
ISO 14001 certification, demonstrating a structured, independently audited environmental management system
Transparency around Scope 3 emissions, the indirect emissions across a contractor's supply chain, and typically the largest and hardest to control part of a project's carbon footprint
B Corp Certification, an independent assessment of social and environmental performance, accountability, and transparency, not a self-reported claim.
A contractor holding genuine, verifiable credentials in these areas will reflect sustainability commitments in practice, not just in pitch documents.
If you want to go further and embed sustainability into the workplace itself once the fit-out is complete, our guide to sustainability ideas in the workplace covers practical measures beyond certification to help guide you in what to look for.
5. Look beyond the portfolio: requesting real-world proof
A polished portfolio shows a contractor's best day. It won't show you how a space performs two years after handover, how issues get resolved once the contractor has left site, or whether previous clients experienced budget and timeline slippage along the way. Push further:
Request site visits to workspaces completed two to three years ago: Do not just rely on recent projects. To properly assess how materials and finishes have actually held up under daily use, consider looking at older projects.
Ask for an uncurated reference list: Rather than a hand-picked selection of the happiest clients, and speak to those references directly about budget and timeline slippage.
Audit the snagging and defects liability process: Ask how the contractor manages post-occupancy issues, including their SLA and response time for emergency mechanical or electrical faults during the standard 12-month defects liability period.
Verify supply chain and product warranties: Confirm that manufacturer warranties for custom joinery, commercial furniture, and technical installations such as HVAC and lighting pass directly and seamlessly to your business, protecting your capital investment long after handover.
This level of due diligence takes more effort than reviewing a portfolio. It also tells you far more about what happens after the ribbon is cut.
6. Office fit out classifications, explained
Shell and Core is the base building structure delivered by the developer. It includes the structural frame, concrete floor, external glazing, and core common services (lifts, toilets, lobbies), but no internal finishes.
Category A (Cat A) delivers a basic, functional but empty space. It typically includes raised access flooring, suspended plasterboard ceilings, basic MEP services, and fire alarms, but is completely unbranded and without furniture.
Category A+ (Cat A+) bridges the gap between Cat A and Cat B, offering a plug-and-play workspace. It includes communal tea points, breakout zones, basic meeting rooms, and furniture, designed for tenants wanting immediate occupancy.
Category B (Cat B) is the fully finished, bespoke corporate fit-out. It includes interior partitions, brand-specific finishes, customised IT/AV infrastructure, private offices, breakout areas, kitchen installations, and all loose furniture.
Key questions to ask prior to appointing a contractor
Will the pitch team be the delivery team, or will the project pass to different staff once the contract is signed?
What is your health and safety record, including RIDDOR-reportable incidents over the past three years?
What evidence can you provide of your financial stability relative to a project of this scale?
What environmental accreditations do you hold, and can you provide supporting documentation?
What is your SLA for emergency call-outs during the defects liability period?
Do manufacturer warranties on furniture, joinery, and technical installations pass directly to us?
Can we speak to references from projects completed at least two years ago?
How will you manage the project if it needs to run alongside our day-to-day business operations?
Frequently Asked Questions
How much does a standard commercial office fit-out cost per sq ft?
Costs vary by specification and location, but a Cat B fit-out in the UK typically ranges from £60 to £150+ per sq ft. Highly technical or high-end fit-outs can exceed this range significantly.
How long does an office fit-out project typically take?
A straightforward Cat B fit-out usually takes eight to sixteen weeks on site, depending on size and complexity. Larger or more technically demanding projects take longer.
Do I need planning permission for an office fit-out?
Most internal fit-out works don't require planning permission, provided they don't alter the building's external appearance or structure. Listed buildings and certain changes of use may require consent, so check with your local planning authority.
What's typically included in a fit-out quote?
A comprehensive quote covers design fees, construction costs, furniture and equipment, technical installations such as IT and AV, and project management fees. Clarify exactly what's included to avoid unexpected additions later.
