Commercial Property Glossary: 60 Terms Every Tenant and Investor Should Know

Commercial property transactions involve a specialist vocabulary. Misunderstanding a clause before signing a lease or completing a purchase can have significant financial consequences. This glossary defines 60 of the most commonly encountered terms in UK commercial property, covering leases, investment, planning, surveying, and finance.

A–D

Alienation clause — A lease provision governing whether and how a tenant can assign the lease to another party, sublet part or all of the premises, or share occupation with a third party. Most commercial leases permit alienation with the landlord's consent, which cannot be unreasonably withheld.

Asset management — The active management of a property or portfolio with the aim of maximising its value and income. This includes negotiating lease renewals, re-letting vacant units, undertaking refurbishment, repositioning assets, and managing disposals.

Assured shorthold tenancy (AST) — A residential tenancy type governed by the Housing Act 1988. Not applicable to commercial property. Included here because it is sometimes confused with commercial licence agreements by occupiers unfamiliar with the distinction.

Break clause — A provision in a commercial lease allowing either the landlord, the tenant, or both parties to terminate the lease before its contractual expiry date at a specified break date or dates, subject to giving the required advance notice and (usually) complying with all lease obligations. Missing the break notice deadline by even one day means the right is lost.

BREEAM — Building Research Establishment Environmental Assessment Method. The UK's leading sustainability rating system for new and existing buildings. Ratings run from Pass, Good, and Very Good, through to Excellent and Outstanding.

Business rates — A property tax levied on non-domestic properties in England, Wales, and Scotland, based on each property's rateable value as assessed by the Valuation Office Agency (VOA) in England and Wales. Small businesses may qualify for small business rates relief or other reliefs that reduce the liability.

Capital allowances — Tax relief available to businesses on qualifying capital expenditure, including certain commercial property fit-out and improvement costs. The specific items that qualify are defined by HMRC and should be confirmed by a specialist adviser.

Covenant strength — A measure of the financial standing of a tenant or landlord, used to assess the risk that they will be unable to meet their obligations under the lease. Assessed by reference to filed accounts, credit ratings, and the nature of the business.

Demise — The specific area of a property that a tenant occupies and is responsible for under the terms of a lease. The demise is defined precisely in the lease — including whether it includes external walls, the floor slab, and the ceiling — and determines the extent of the tenant's repairing obligations.

Dilapidations — A claim by a landlord against a tenant for the cost of repairing, reinstating, or decorating a property that has not been maintained to the standard required by the lease. Dilapidations are assessed at or near the end of the lease and can be a source of significant dispute.

Drone survey — An aerial survey using an unmanned aerial vehicle (UAV) to inspect and document roofs, façades, and large or complex sites. Increasingly used in commercial property due diligence as an efficient alternative to scaffold or rope access inspections.

E–J

EPC (Energy Performance Certificate) — A certificate rating a property's energy efficiency on a scale from A (most efficient) to G (least efficient). Under Minimum Energy Efficiency Standards (MEES) regulations, landlords in England and Wales cannot let commercial properties with a rating below E. The minimum threshold is expected to increase in the coming years.

Equivalent yield — A single yield figure, calculated by a valuer, that blends the passing rent, the estimated rental value (ERV), and the timing of all future lease events (rent reviews, breaks, and expiry) to express the overall return from a property investment.

FRI lease (Full Repairing and Insuring) — A lease in which the tenant is responsible for all repairs and maintenance of the property — internal and external — and for insuring the building. The most common form of commercial lease in the UK. Under an FRI lease, the landlord receives a "clear" rent with minimal management obligations.

Floor area (GIA / NIA) — Gross Internal Area (GIA) is the total floor area measured within the external walls, including internal partitions and columns. Net Internal Area (NIA) is the usable space available to the occupier, excluding structural elements, toilets, stairwells, and circulation areas. Office space is typically quoted in NIA; industrial space in GIA.

Force majeure — A clause in a commercial lease or contract excusing a party from performing their obligations in circumstances wholly beyond their reasonable control, such as natural disasters or acts of war. Force majeure clauses are interpreted strictly by UK courts and rarely apply to commercial or financial difficulties.

Gearing — The ratio of debt to equity in a property investment. A highly geared investment amplifies both returns in rising markets and losses in falling ones. Commercial mortgage lenders typically limit gearing to 60–75% LTV.

Gross development value (GDV) — The estimated total market value of a development project once it is complete and fully let or sold. Used by developers and their lenders to assess the viability and profitability of a development scheme.

Heads of Terms (HoTs) — A non-binding document — sometimes called a "term sheet" — setting out the agreed commercial terms of a proposed letting or sale before solicitors are instructed to draft the formal legal documents. Key points typically covered include rent, lease length, break clauses, repairing obligations, and any incentives.

IRI lease (Internal Repairing and Insuring) — A lease in which the tenant is responsible only for internal repairs and decoration. The landlord retains responsibility for the external structure, roof, and main services. More common in multi-let buildings where external maintenance is managed by the landlord and recovered via a service charge.

IRR (Internal Rate of Return) — A measure of investment performance expressing the discount rate at which the net present value of all future cash flows from an investment — including purchase costs, rental income, and sale proceeds — equals zero. Used alongside initial yield as a performance metric when comparing investment opportunities.

K–P

Landlord and Tenant Act 1954 — The principal UK legislation governing the rights of commercial tenants at the end of a lease. The Act gives qualifying tenants the right to renew their lease on broadly the same terms unless the landlord can establish statutory grounds for possession. Landlords and tenants can agree to exclude ("contract out of") the Act's protections before the lease is granted.

Lease premium — A capital payment made by a tenant to a landlord at the start of a lease, in addition to or instead of ongoing rent. Typically used to secure a longer lease term, a below-market rent, or a particularly desirable location. Also payable when a tenant assigns a lease at a value above its passing rent.

Licence — A personal permission to occupy a property granted by the owner. Unlike a lease, a licence does not create a legal interest in the property and does not attract the statutory protections of the Landlord and Tenant Act 1954. Common in serviced offices, short-term arrangements, and storage facilities.

Lot size — In the context of a property auction or portfolio sale, the lot size refers to the individual unit of sale — either the individual property within a portfolio, or the purchase price associated with it.

MEES (Minimum Energy Efficiency Standards) — Regulations in England and Wales requiring landlords of commercial properties to achieve a minimum EPC rating before letting. The current minimum is EPC rating E. The government has proposed raising this to C and ultimately B for commercial properties, though implementation timescales have been subject to change.

Net initial yield (NIY) — The annual passing rent expressed as a percentage of the total acquisition cost, including all purchaser's costs such as SDLT, agent fees, and legal fees. The net initial yield is a more accurate measure of the income return on investment than the gross yield.

Net present value (NPV) — The value today of a future stream of cash flows, discounted at a required rate of return. Used in investment appraisal to compare the value of receiving income in the future against the cost of the investment today.

Occupational lease — A lease granted to a tenant who occupies and uses the property for the purposes of their business, as opposed to a head lease or investment structure. The term distinguishes between a letting to an operational tenant and the sale of a tenanted investment to another investor.

Overriding interests — Rights or interests affecting a property that are legally binding on a new owner even though they are not registered at HM Land Registry. These can include certain easements, local land charges, and rights of persons in actual occupation. Identified through searches and enquiries during the conveyancing process.

Passing rent — The rent actually being paid by a tenant under the current terms of the lease. The passing rent may be above (over-rented) or below (reversionary) the current open market rent depending on when the lease was granted and how market rents have moved since.

Practical completion — The stage in a construction or fit-out project at which the works are substantially complete — the property can be used for its intended purpose — even if minor snagging items remain outstanding. Practical completion typically triggers the commencement of the lease term and the tenant's repairing obligations.

Q–Z

Rack-rented — A property where the passing rent is equal to or very close to the current open market rent (Estimated Rental Value). A rack-rented investment offers no "reversionary" potential from rental growth at review, but the passing rent is fully supported by current market evidence.

Rateable value (RV) — The value assigned to a non-domestic property by the Valuation Office Agency (VOA) for the purpose of calculating business rates. Based on an estimate of the annual open market rent at a fixed valuation date. Rateable values are periodically reassessed at a revaluation.

RICS (Royal Institution of Chartered Surveyors) — The professional body for surveyors in the UK and internationally. Chartered surveyors holding the MRICS (Member) or FRICS (Fellow) designations are bound by RICS professional standards and ethics. RICS membership is a recognised mark of professional competence in commercial property.

Schedule of condition — A written and photographic record of the condition of a property at the start of a lease. When incorporated into the lease by reference, it limits the tenant's repairing and reinstatement obligations at the end of the term to returning the property to no better than the condition recorded at the outset.

Service charge — A contribution by tenants in a multi-let building towards the shared costs of operating, maintaining, and managing the common parts and shared services — including lifts, common area cleaning, building insurance, and property management fees. Always request service charge accounts before signing a lease in a multi-let building.

SDLT (Stamp Duty Land Tax) — A tax on property transactions in England, levied on the purchase price of land and buildings. Different rates apply to residential and non-residential transactions. Payable within 14 days of completion. Scotland and Wales operate equivalent taxes under separate legislation.

Subletting — The grant of a lease by a tenant (as landlord) to a third party (the sub-tenant) over all or part of the premises. The original tenant remains liable to the head landlord under the terms of the head lease. Most commercial leases permit subletting subject to the landlord's consent.

Title — The legal right to own a property. Freehold title confers outright, indefinite ownership. Leasehold title confers the right to occupy for the duration of the lease term, after which ownership reverts to the freeholder.

Upward-only rent review — A provision in a commercial lease allowing the rent to be reviewed to open market rent at specified intervals, but only upwards. The rent cannot fall below the passing rent even if open market rents have declined since the last review. The standard form in most UK commercial leases.

Void period — A period during which a commercial property is unoccupied and generating no rental income. The landlord remains liable for business rates (after the initial exemption period), maintenance, and insurance costs during a void. Void periods are a primary risk factor in commercial property investment.

Yield — Annual rental income expressed as a percentage of the capital value or purchase price of a property. The primary measure of income return in commercial property investment. A lower yield indicates a higher price relative to income (and typically a more in-demand asset); a higher yield indicates a lower price relative to income (and typically higher risk).

Yield compression — A reduction in yield caused by rising capital values without a proportionate increase in passing rent. Reflects increased investor demand for a particular asset class, sector, or location. Yield compression benefits existing owners but reduces the income return available to new purchasers.

Zone A (Zoning) — A method of measuring and valuing retail shop floor space. The area immediately behind the shop frontage is designated Zone A and given the highest value per sq ft; subsequent zones of equal depth (typically 6.1m) are valued at half the rate of the zone in front. Zone A value (expressed as £ per sq ft ITZA — in terms of Zone A) is the standard basis for comparing retail rents.

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Frequently Asked Questions

What is an FRI lease in simple terms?

A Full Repairing and Insuring (FRI) lease is a commercial lease in which the tenant takes on responsibility for all repairs, maintenance, and insurance of the property. The landlord receives the rent without deduction and is not responsible for the building's upkeep during the lease term. It is the standard lease structure in the UK commercial property market.

What is the difference between a lease and a licence?

A lease creates a legal interest in a property for a defined term and gives the tenant statutory rights, including (in most cases) the right to renew at expiry under the Landlord and Tenant Act 1954. A licence is a personal permission to occupy that does not create a legal interest and can be terminated more easily. Serviced offices are typically granted by licence rather than lease.

What are dilapidations and how can I limit my exposure?

Dilapidations is the landlord's claim against a tenant at the end of a lease for the cost of repairing or reinstating the property to the condition required by the lease. The most effective way to limit exposure is to agree a Schedule of Condition at the start of the lease — a photographic and written record of the property's condition at the outset — and have it incorporated into the lease so that your repairing obligation is limited to maintaining the property in that condition, rather than returning it to a potentially higher standard.

What is the Landlord and Tenant Act 1954 and can I opt out of it?

The Landlord and Tenant Act 1954 gives most commercial tenants the statutory right to renew their lease on broadly the same terms when it expires. A landlord can only refuse renewal on specified statutory grounds, such as redevelopment or owner-occupation. Landlords and tenants can agree to exclude these protections (known as "contracting out") before the lease is granted, subject to a formal notice procedure. Contracted-out leases are common for shorter terms.

What does "upward-only rent review" mean in practice?

An upward-only rent review clause means that when the rent is reviewed at the specified intervals — typically every 3 or 5 years — the rent can be increased to reflect current open market rents, but cannot fall below the current passing rent even if market rents have declined. In a falling market, an upward-only review clause means the tenant continues to pay above-market rent until the lease expires or a break clause can be exercised.

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Understanding the language of commercial property before you sign anything is one of the most effective ways to protect your interests. If you are looking for commercial space, post your requirement on REmatch — describe what you need and let landlords and agents respond directly to your brief.