A building lease is a commercial contract that gives a tenant the right to occupy and use a building, or a portion of one, for a set period in exchange for rent. Most run three to ten years, with five years being the most common term. Unlike a residential lease, almost every meaningful term is negotiable rather than set by statute, so what you sign determines what you pay and what you are exposed to.
What a Building Lease Is Not
A building lease is commercial, not residential. Residential tenants in most jurisdictions get a thick layer of statutory protections: deposit limits, habitability standards, strict eviction procedures. Commercial tenants generally do not. The law assumes both sides can protect themselves through negotiation, which puts the weight on the lease document itself.
It is also not a ground lease. A ground lease covers the land, usually so the tenant can build on it, and runs 50 to 99 years because the tenant needs time to justify the construction. Improvements typically revert to the landowner when the lease ends.
A lease is not a license either. A license is revocable permission to use space for a specific purpose, without exclusive possession or any property interest, like a vendor booth at a conference. And a lease grants temporary use, where a purchase agreement transfers ownership outright.
Types of Building Leases
Building leases are categorized mostly by how operating expenses are split between landlord and tenant. That split drives your real cost and how predictable it will be.
Gross Lease
You pay one flat rent. The landlord covers property taxes, insurance, and building maintenance out of that figure. Those expenses are baked into the rent, so you are paying for them indirectly, but a tax spike or an expensive roof repair will not land on you mid-term. This is the most predictable structure for a tenant.
Net Leases
Net leases drop the base rent and push operating costs onto the tenant. They come in several forms:
- Single net (N): base rent plus your share of property taxes. The landlord handles insurance and maintenance.
- Double net (NN): base rent plus taxes and insurance. The landlord still covers structural maintenance and common areas.
- Triple net (NNN): base rent plus taxes, insurance, and common area maintenance. In a multi-tenant building, each tenant pays a pro-rata share, usually calculated by dividing leased square footage by total leasable area.
- Absolute net: the tenant bears every expense, including rebuilding after a catastrophe. Rare, and the riskiest for the tenant.
Triple net leases are extremely common for freestanding retail and industrial properties. They look cheaper on paper because the base rent is lower, but once the pass-through costs are added up, total occupancy cost can match or exceed a gross lease.
Modified Gross Lease
A modified gross lease splits the difference. Landlord and tenant negotiate which expenses each side covers. A typical arrangement has the landlord paying a baseline level of operating expenses, with the tenant picking up any increases above that baseline over the term. The tenant gets predictability early; the landlord gets protection against rising costs later.
Percentage Lease
Retail tenants, especially in shopping centers, sometimes see percentage leases. On top of base rent, the tenant owes the landlord a percentage of gross sales above a threshold called the breakpoint. A natural breakpoint is calculated by dividing annual base rent by the percentage rate. The structure ties the landlord’s return to tenant performance.
The Clauses That Decide Your Real Cost and Risk
Rent and Escalations
Commercial rent is typically quoted per square foot per year. A 2,000-square-foot office at $30 per square foot comes to $60,000 annually, paid monthly. Rent almost never stays flat across the term. Fixed escalations raise it by a set dollar amount or percentage each year. CPI escalations tie increases to the Consumer Price Index, so a 3% CPI year raises rent 3%. Negotiate a cap on CPI escalations, often 3% to 5%, to avoid getting hammered in high-inflation years. Watch for floors that guarantee the landlord a minimum increase even when inflation is flat.
Common Area Maintenance Charges
In a net or triple net lease, CAM charges deserve careful reading. They cover landscaping, parking lot upkeep, snow removal, elevator maintenance, lobby cleaning, security, and property management, and some landlords add an administrative fee on top. Vague CAM language is one of the most common sources of landlord-tenant disputes. Push for a cap on annual CAM increases and an audit right that lets you verify the landlord’s expense calculations.
Permitted Use and Exclusivity
The use clause defines what business activities you can conduct in the space. A narrow use clause can block you later if you want to pivot or add a product line, so negotiate the broadest language the landlord will accept.
An exclusivity clause works the other direction, protecting you from competition within the same property. An ice cream shop in a shopping center, for example, might secure one that bars the landlord from leasing to another ice cream seller on-site. Landlords typically carve out exceptions for pre-existing tenants, for incidental sales (a restaurant offering ice cream as one dessert), and for parts of the property the landlord may later sell. The clause is only as strong as those carve-outs are narrow.
Maintenance and Repair
Who fixes what is a constant source of conflict. Building leases typically assign structural repairs (roof, foundation, exterior walls) to the landlord and interior maintenance to the tenant, but this varies widely by lease type. In a triple net lease, the tenant may be responsible for everything. The lease should spell out HVAC, plumbing, electrical, and specialized equipment specifically. Ambiguous maintenance language almost always hurts the tenant.
Insurance
Tenants generally carry commercial general liability insurance and property coverage for their own contents and improvements. Landlords typically carry structural coverage on the building. In triple net leases, the tenant often reimburses the landlord’s insurance premiums as part of operating expenses. The lease usually requires the tenant to name the landlord as an additional insured.
Force Majeure
Force majeure clauses excuse performance delays caused by events outside either party’s control: natural disasters, wars, government-ordered shutdowns. The catch is that many of these clauses excuse delayed construction or delivery of possession but do not excuse the tenant from paying rent. Some leases do abate rent when the property becomes physically unusable from a force majeure event, but do not assume yours does. Check whether the clause explicitly addresses rent, not just general “performance.”
Assignment and Subletting
If your business grows, shrinks, or closes, you will want a way out of the space. An assignment transfers your entire interest to a new tenant. A sublease rents all or part of the space to a subtenant while you stay on the lease. Most commercial leases prohibit both without the landlord’s prior written consent. One detail many tenants miss: in an assignment, the original tenant usually stays liable unless the landlord agrees to a novation. In a sublease, the original tenant is always primarily liable to the landlord.
Up-Front Money and Personal Exposure
Commercial security deposits typically have no statutory cap. The standard starting point is one month’s rent, but landlords may demand more based on tenant financials, lease term, or the cost of tenant improvements the landlord is funding. Established businesses can sometimes negotiate the deposit down or substitute a letter of credit, which ties up less cash.
Personal guarantees are where exposure gets serious. If you lease through an LLC or corporation, the landlord may require one or more owners to personally guarantee the lease. A full guarantee makes you personally liable for every obligation, including rent for the entire remaining term if the business fails. On a five- or ten-year lease that number can be enormous. Tenants with leverage push for a limited or burn-off guarantee, where the guaranteed amount decreases over time and eventually expires. Some markets use a “good guy” guarantee, where personal liability ends when the tenant surrenders the space in good condition and pays all rent through the surrender date.
How the Deal Gets Built: LOI and Work Letter
Negotiations usually open with a letter of intent. The LOI is a short document outlining the fundamental business terms both sides have agreed to: the space, the rental rate, the term, tenant improvement allowance, security deposit, and any special provisions like early termination or expansion rights. Most LOIs are explicitly non-binding, so neither side can be held to the terms if full lease negotiation falls apart, though confidentiality provisions and broker disclosures within an LOI are typically binding.
Most commercial spaces need renovation before a new tenant can occupy. The work letter, attached as an exhibit to the lease, governs that process. It separates the landlord’s base building work (HVAC, electrical infrastructure, fire safety systems) from the tenant’s leasehold improvements, which are the build-out specific to your business.
The centerpiece is the tenant improvement allowance, or TIA, usually expressed as dollars per square foot. If the landlord offers $20 per square foot on a 3,000-square-foot space, that is $60,000 toward construction. Anything above comes out of your pocket. The TIA is negotiable and often depends on lease length, creditworthiness, and market conditions. Longer commitments typically unlock larger allowances because the landlord recoups the investment over more rent years. A well-drafted work letter also covers contractor selection, change order approval, a construction timeline, and a clear definition of substantial completion that triggers your rent obligation. If the landlord is managing construction and runs late, the work letter should provide rent abatement for the delay, and some tenants negotiate a termination right if the space is not delivered within a specified window.
End-of-Lease and Default Scenarios
Holdover
Staying past your lease expiration without a new agreement puts you in holdover status, and it is expensive by design. Most commercial leases set holdover rent at 120% to 200% of the rate in effect at expiration. The landlord retains the right to evict, and many leases also make the tenant liable for consequential damages, like lost rent from a replacement tenant who walked away because you did not vacate. If you think you might need extra time, negotiate a short-term extension option upfront rather than relying on holdover terms that are written to punish you.
Default and Remedies
Default clauses define what counts as a violation and what happens next. Monetary defaults such as missed rent usually come with a short cure period, often five to ten business days after written notice. Non-monetary defaults, like violating the use clause or failing to maintain insurance, typically allow around 30 days to cure, with extensions when the tenant is making good-faith efforts to fix the problem.
If a default is not cured, the landlord’s remedies usually include terminating the lease and pursuing eviction, suing for unpaid rent and damages, drawing on the security deposit, and accelerating the remaining rent due under the lease. Acceleration clauses are particularly dangerous because they can make you liable for the entire remaining rent balance in one lump sum, discounted to present value. Negotiate caps on these damages and make sure the landlord has a duty to mitigate by making reasonable efforts to re-lease the space.