Financing an office build or renovation can be done in several ways, including commercial mortgages, bridging finance, business loans and commercial development finance. The right option depends on the size of the project, whether you own the building, how much money you need and how quickly the work needs to be completed. For businesses looking to create a new workspace or improve an existing one, finance can make a major project more affordable without using all their available cash reserves.
How Much Does an Office Build or Renovation Cost in London?
A light office renovation can cost £40 to £95 per sq foot and around £400-£600 per sq foot if you are building a new office from scratch.
| Type of project | Indicative cost per sq ft |
|---|---|
| Light office renovation | £40–£95 |
| Major office refurbishment | £175–£300+ |
| Office fit out | £148–£359 |
| Building a new office from scratch | £400–£600 |
These figures are based on London industry benchmarks, including Knight Frank’s 2026 refurbishment guide and Cushman & Wakefield’s 2026 fit-out guide. They are not fixed quotations and the scopes of work differ.
Location also plays a part. Prime areas such as office spaces in Mayfair, the West End and the City can attract higher costs than areas further out, such as Croydon, Stratford and Hammersmith.
For example, building a new 10,000 sq ft office in Central London could cost approximately £4 million to £6 million before professional fees, VAT and other additional costs.
How Much an Office Build and Renovation Costs Based on Square Feet
| Type of project | Cost per sq ft | 1,000 sq ft | 3,000 sq ft | 5,000 sq ft | 10,000 sq ft |
|---|---|---|---|---|---|
| Light office renovation | £40–£95 | £40k–£95k | £120k–£285k | £200k–£475k | £400k–£950k |
| Major office refurbishment | £175–£300+ | £175k–£300k+ | £525k–£900k+ | £875k–£1.5m+ | £1.75m–£3m+ |
| Office fit out | £148–£359 | £148k–£359k | £444k–£1.077m | £740k–£1.795m | £1.48m–£3.59m |
| Building a new office from scratch | £400–£600 | £400k–£600k | £1.2m–£1.8m | £2m–£3m | £4m–£6m |
What Are the Different Ways to Finance an Office Build or Renovation?
There are several finance options available to businesses and commercial property owners.
1. Commercial Mortgages
A commercial mortgage is a long-term loan used to purchase or refinance commercial property. It can be suitable for businesses looking to buy their own office premises rather than rent.
Depending on the lender and the circumstances, borrowing may also help fund improvements to the property. The building is normally used as security against the loan, and repayments are made over an agreed period.
2. Bridging Finance
Bridging finance is a short-term funding option that can help businesses access money quickly and can be useful when purchasing an office that needs renovation before it can be occupied or rented out. For example, a business might use bridging finance to purchase an outdated office, complete the refurbishment and then refinance onto a longer-term commercial mortgage.
However, bridging finance usually carries higher interest rates, so having a clear repayment or exit strategy is essential.
3. Unsecured Business Loans
An unsecured business loan allows a company to borrow money without putting a specific property or asset forward as security.
This can be useful for smaller office renovations, including new furniture, meeting rooms, flooring, lighting and general improvements.
The lender will assess the company’s finances, credit history and ability to repay. Interest rates can be higher than secured borrowing, depending on the business and loan amount.
4. Secured Business Loans
A secured business loan requires an asset to be used as security. This could be a commercial property or another suitable business asset.
It can allow companies to access larger amounts of funding, potentially at more competitive interest rates than unsecured borrowing. However, the asset could be at risk if repayments are not maintained.
5. Commercial Development Finance
Commercial development finance is generally designed for larger projects, including building an office from scratch, substantial redevelopment or major structural renovations.
Funding can cover land or property acquisition and construction costs, with money often released in stages as work progresses.
Lenders will usually assess the development plans, construction budget, expected end value and the proposed exit strategy.
Compare The Rates For Office Build Finance
| Finance option | Indicative interest rate / APR | Typical borrowing amount | Typical loan duration |
|---|---|---|---|
| Commercial mortgage | 5.5%–9% p.a. | £25,000 to £25m+ | 5–25 years (some up to 30) |
| Bridging finance | 0.55%–1.25% per month (approximately 6.6%–15% p.a.) | £25,000 to £50m+ | 1–18 months (some up to 60) |
| Unsecured business loan | 8%–40% APR | £1,000–£250,000 typically | 1–5 years |
| Secured business loan | 7%–18% APR | £30,000–£875,000 typically | 1–5 years (some up to 25) |
| Commercial development finance | 8%–11% p.a. | £100,000 to £50m+ | 6–24 months typically |
What Are the Benefits of Using Finance for an Office Build?
- Spread the cost and protect cash flow
- Create a bespoke workplace to boost company brand perception and value
- Attract best staff and employees
- Return on investment
Firstly, it allows companies to spread the cost of a major project rather than paying for everything upfront. This helps protect cash flow and leaves money available for everyday business expenses, staff and future investment.
Secondly, it allows businesses to create a workspace that supports their long-term ambitions. A larger office, improved facilities and modern technology can help attract employees, encourage collaboration and create a better working environment.
Major companies recognise the value of investing in their workplaces. Google, for example, has developed its new Platform 37 headquarters at King’s Cross, covering approximately 60,400 square metres and designed to accommodate up to 4,500 people.
While this is a major corporate investment, it demonstrates how businesses can use office development to support growth, innovation and their wider operations.
Do You Get a Return on Investment From Building an Office?
An office build or renovation can deliver a return on investment (ROI), although this is not guaranteed. For businesses that own their premises, improvements may increase the property’s market value and make it more attractive to future buyers or tenants.
For businesses occupying their own offices, the return may come through improved staff retention, productivity, reduced running costs and the ability to accommodate more employees.
For landlords and commercial property investors, a modern, energy-efficient office can attract stronger tenants and potentially achieve higher rental income.
It is important to compare the expected financial benefits against the cost of borrowing, interest payments and ongoing maintenance.
Do You Need Landlord’s Permission or Planning Permission?
If you rent your office, you will usually need to check your lease and obtain the landlord’s written consent before carrying out significant alterations. This may include structural changes, new partitions, changes to services or alterations to the building’s appearance.
Planning permission depends on the work involved. Simple internal alterations will not normally require planning permission, but structural changes, extensions and certain changes to the building’s use may need approval.
You may also need building regulations approval for certain alterations, including electrical, heating, ventilation and structural work.
It is always worth speaking to the local planning authority, landlord and relevant professionals before starting work.
Finding the Right Finance for Your Office Project
Whether you are renovating an existing office, fitting out a new commercial space or building something from scratch, choosing the right finance is an important part of the process.
Compare the available funding options, consider the total cost of borrowing and make sure repayments are affordable. With the right finance in place, businesses can create a workspace that supports their future growth without putting unnecessary pressure on their cash flow.
