Whether you’re fitting out a new office, refurbishing a retail unit, or transforming a leisure space, the planning phase determines whether the project runs smoothly. Most fit out problems — delays, cost overruns, design compromises — trace back to decisions (or the absence of them) made before a single contractor is appointed.
This guide walks through the key stages of planning a commercial fit out, from initial brief to appointment of a contractor.
Step 1: Define Your Brief
Before you speak to any contractor or designer, spend time articulating what you actually need from the space. This means going beyond aesthetics and thinking about:
- How many people will use the space, and how will they work?
- What functions need to be accommodated — individual desks, collaborative areas, meeting rooms, reception, breakout?
- Are there regulatory requirements — DDA compliance, fire escape routes, ventilation standards?
- What’s the target date for completion, and why?
- What’s the budget, and is it realistic for the scope?
A clear brief doesn’t need to be a lengthy document. But it needs to answer these questions. Vagueness at brief stage turns into variation orders at construction stage.
Step 2: Understand Your Lease
If you’re fitting out a leased commercial property, your lease will contain obligations and restrictions that directly affect what you can build. These include:
- Licence to alter requirements — most landlords require formal approval before structural changes, M&E alterations, or any work affecting the fabric of the building
- Reinstatement obligations — you may be required to return the space to its original condition at lease end (dilapidations)
- Approved contractor lists — some landlords specify which contractors can work in their building
An experienced fit out contractor can help you navigate these requirements. Eden Build regularly coordinates licence to alter applications and liaises with landlords and their surveyors on behalf of clients.
Step 3: Set a Realistic Budget
Commercial fit out costs vary enormously depending on specification, location and sector. As a very rough guide, a standard office Cat B fit out in the UK typically ranges from £40–£80 per square foot depending on quality of finishes and M&E specification. London costs tend to sit at the higher end.
Build in a contingency — 10% is a reasonable starting point for most projects. This isn’t pessimism; it’s good financial management. Fit out projects involve existing buildings with unknown conditions, and surprises happen.
Step 4: Appoint the Right Contractor — Early
One of the most common planning mistakes is treating contractor appointment as something that happens after all the decisions have been made. In reality, bringing in an experienced contractor at feasibility stage saves time and money.
Early contractor involvement (ECI) allows the contractor to:
- Identify buildability issues before they become programme problems
- Provide early-stage cost advice to test design options against budget
- Begin procurement of long-lead items — specialist joinery, structural steel, M&E equipment
- Engage with the landlord and building management team ahead of the construction phase
Step 5: Agree Programme and Phasing
A detailed programme — showing every stage of work, who is responsible, and the critical path — is essential for any commercial fit out. This is especially true for occupied buildings where the works need to be phased around your business operations.
At Eden Build, we produce a full construction programme before work starts, agreed with you and shared with all relevant parties. We don’t start on site without one.
Step 6: Plan for Handover
Fit out projects often focus heavily on construction and underweight the handover stage. Good handover management includes:
- A structured snagging process with clear sign-off criteria
- O&M manuals and commissioning records for all M&E systems
- Staff familiarisation with new systems — especially BMS, AV and access control
- A defects liability period with a named contact for post-handover issues
Common Mistakes to Avoid
- Starting design before the brief is agreed — leads to wasted fees and redesign
- Underestimating M&E costs — often 30–40% of total fit out spend
- Appointing on price alone — the cheapest tender rarely represents the best value
- Leaving insufficient time for landlord approvals — these can take 4–8 weeks
- Not planning for IT and AV infrastructure early enough — cabling is much cheaper to install before walls go up
Talk to Eden Build
If you’re at the planning stage of a commercial fit out and want to speak with a contractor that’s delivered across offices, retail, leisure and education – Eden Build is here to help. We offer free initial consultations, site surveys, and cost plans. Get in touch with our team today.