What Is a Work Letter?
A work letter (also called a tenant improvement agreement, TI exhibit, or construction rider) is a lease exhibit that defines exactly who builds what, who pays for it, and what the finished space must look like. It governs the entire construction relationship between landlord and tenant before the lease term even begins.
In a typical commercial deal the lease itself establishes the rent and legal obligations; the work letter governs the physical transformation of raw shell space into an occupied suite. Without a detailed work letter you're operating on a handshake — and handshakes collapse when the contractor is two weeks over schedule and $60,000 over budget.
Key insight: A work letter is not optional in any deal where the landlord contributes money or labor. Even in "as-is" leases, a brief work letter documenting the as-is condition protects both parties from future claims.
The Two Main Work Letter Structures
Work letters generally fall into two categories, and the structure you use determines who controls the buildout — and who bears the risk:
| Structure | Who Manages Construction | Who Hires Contractors | Risk Profile | Best For |
|---|---|---|---|---|
| Landlord Work | Landlord | Landlord | Tenant bears delay risk if rent starts on "substantial completion" | First-time tenants, shell space, major buildouts |
| Tenant Work / TI Allowance | Tenant | Tenant (with landlord approval) | Tenant controls quality; landlord bears cost to the TI cap | Sophisticated tenants, custom buildouts, branded spaces |
| Combination | Split by scope | Split | Coordination risk between parallel work streams | Multi-phase projects, large blocks |
Landlord Work vs. TI Allowance: A Deep Dive
Landlord Work Approach
Under a landlord work structure, the landlord agrees to deliver the space in a defined "finished" condition described in the work letter. The tenant specifies requirements (ceiling height, power capacity, HVAC zones) and the landlord hires the contractor, manages the project, and delivers a completed space.
The tenant's leverage: You negotiate the specifications. The more precise your construction document requirements, the harder it is for the landlord to substitute cheaper materials or trim scope.
The tenant's risk: If the landlord's contractor runs late, you may still be obligated to start paying rent on the "substantial completion" date — even if the space isn't truly move-in ready. Always negotiate a punch-list period and define substantial completion narrowly.
TI Allowance Approach
Under a TI allowance structure, the landlord funds construction up to a capped dollar amount per square foot. The tenant manages the buildout — selecting architects, engineers, general contractors, and subcontractors (subject to landlord approval rights).
The TI allowance is typically expressed as a dollar figure per rentable square foot. In 2026, market TI allowances in major markets range significantly by property class:
| Market | Class A Office TI ($/RSF) | Class B Office TI ($/RSF) | Retail TI ($/RSF) | Industrial TI ($/RSF) |
|---|---|---|---|---|
| New York | $120–$200 | $70–$120 | $60–$100 | $15–$35 |
| San Francisco | $110–$180 | $60–$110 | $55–$90 | $12–$30 |
| Chicago | $80–$140 | $50–$90 | $45–$75 | $10–$25 |
| Dallas | $70–$120 | $45–$80 | $40–$70 | $8–$20 |
| Secondary Markets | $50–$90 | $30–$65 | $30–$55 | $5–$15 |
Watch out: TI allowances are frequently expressed in "per rentable square foot" terms, which includes a load factor on top of your actual usable space. A $80/RSF allowance in a space with a 15% load factor gives you effectively $68/USF of actual buildout money.
Critical Work Letter Provisions
1. The Construction Schedule & Commencement Date
One of the biggest fights in commercial tenancy happens before you even move in: When does rent start? The work letter must specify whether the commencement date is:
- Fixed date — rent starts on a specific calendar date regardless of construction status
- Substantial completion date — rent starts when construction reaches a defined completion milestone
- Occupancy date — rent starts when tenant actually takes possession
Tenants should strongly prefer substantial completion or occupancy triggers. If you must accept a fixed date, negotiate a "free rent" period that covers likely construction overruns.
2. Definition of Substantial Completion
Courts have litigated this phrase extensively. Your work letter should define substantial completion specifically — ideally requiring:
- Certificate of occupancy issued (or temporary CO for staged projects)
- Mechanical, electrical, plumbing systems operational
- Punch list items documented and no more than 5% of total work value outstanding
- Space legally occupiable and accessible
3. The Tenant Delay Clause
Watch this one carefully. Tenant delay provisions allow the landlord to move up the commencement date (and start charging rent) if the tenant causes delays. Common triggering events include:
- Late submission of construction documents or approvals
- Tenant-requested changes after construction begins
- Failure to approve contractor or materials within specified timeframes
- Tenant's contractor or consultants delaying landlord's work
Negotiate to require: (a) written notice of any alleged tenant delay within 3 business days of occurrence, (b) a minimum delay threshold before the provision triggers (e.g., delays must exceed 5 cumulative days), and (c) a cure period for the tenant to remedy the delay.
4. Scope of Work Description
The most frequent disputes arise from ambiguous scope language. A professional work letter should include:
- Approved construction documents (drawings and specifications) attached as exhibits
- List of finishes with brand, model, and grade specifications (e.g., "Shaw contract carpet, Claridge series" not just "carpet")
- HVAC system specifications including zones, airflow rates, and control systems
- Electrical capacity (amps, circuits, subpanel location)
- Plumbing rough-in locations and capacities
- Ceiling system type and height
- Partition heights and construction type (drywall vs. demountable)
5. Change Orders
Once construction is underway, changes are expensive and contentious. Your work letter should specify:
- Change order process: written request → cost estimate → written approval required before work proceeds
- Tenant-directed changes over TI allowance: who pays the overage (typically tenant, but negotiate for landlord markup caps — landlords often charge 5–15% on change order management)
- Change order timeline: landlord must provide cost estimate within 5 business days; tenant must approve within 3 business days
- Landlord markup cap: cap any landlord overhead or profit charge on change orders at 10% or less
TI Allowance Mechanics: How the Money Flows
Understanding how TI funds are actually disbursed prevents cash flow surprises during construction. Most TI allowance structures work as follows:
Typical TI Draw Process:
1. Tenant submits draw request with AIA G702/G703 forms + lien waivers
2. Landlord reviews and approves (typically 10-15 business day review period)
3. Landlord disburses funds (minus any retainage holdback)
4. Retainage (typically 10%) released upon substantial completion + final lien waivers
─────────────────────────────────────────
Example: $500,000 TI allowance on 5,000 RSF @ $100/RSF
Construction cost: $475,000 (within allowance)
Per draw: Tenant pays GC, submits for reimbursement
Final retainage holdback: $47,500 (10% of $475,000)
Timing: Expect 30–60 days total from draw submission to receipt
Cash flow reality: Under a reimbursement model, the tenant must fund construction out of pocket and get repaid. On a $500,000 buildout with 45-day reimbursement cycles, you may need $150,000–$200,000 in accessible capital during construction. Negotiate for direct payment to contractors instead of reimbursement where possible.
Allowance Expiration & Forfeiture
Most TI allowances include an expiration date — typically 12 to 18 months after the lease commencement date. Unused TI funds are forfeited, not refunded. This creates a powerful incentive for the landlord to delay your construction while the clock runs. Negotiate:
- An allowance "use-it-or-lose-it" date tied to construction completion milestones, not lease commencement
- The right to apply unused allowance to future capital improvements with landlord consent
- Or in some markets: the right to apply unused TI to free rent
Scope Disputes: How They Start & How to Win
Scope disputes are among the most expensive commercial lease litigation matters. A typical scope dispute follows a predictable pattern:
- Ambiguous specification — the work letter says "commercial-grade finishes" without defining what that means
- Contractor substitution — landlord's contractor uses a lower-grade material when original spec is unavailable or over budget
- Tenant objection — tenant discovers the substitution at or after substantial completion
- Landlord defense — landlord argues substantial compliance, or that tenant approved through inaction
- Holdover & leverage loss — tenant is stuck: move in and waive objections, or delay occupancy and face double rent
Critical: Once you accept keys and occupy the space, it becomes very difficult to later claim the buildout was deficient. Always conduct a formal pre-occupancy walk-through with written documentation of all punch-list items before taking possession.
Protecting Yourself from Scope Disputes
- Attach complete construction drawings — verbal descriptions invite substitution arguments; drawings don't
- Specify substitution approval rights — require landlord to obtain written tenant consent before substituting any specified material
- Hire your own project manager — even a part-time owner's rep ($3,000–$8,000 on a mid-size project) can catch substitutions before they're buried in walls
- Stage payments to completion milestones — if you're the one paying, don't release final payment until punch list is fully complete
- Build in inspection rights — the right to inspect work at defined construction milestones, with copies of all inspection reports
Landlord Default on Work Letter Obligations
What happens if the landlord simply doesn't complete the work? Your remedies depend on what the lease says — and many standard-form leases give tenants surprisingly few options short of termination.
Negotiate for explicit remedies including:
- Rent abatement for each day of delay beyond a specified outside date
- Self-help rights — the right to complete the work yourself and offset costs against rent if the landlord is in default for more than 30 days
- Lease termination right — if substantial completion hasn't occurred within 90–180 days of the target date, tenant may terminate without penalty
- Liquidated damages — a specified daily dollar amount for delay (rare to obtain, but worth asking)
Work Letter Pre-Signing Checklist
- Construction drawings and specifications attached as exhibits — not just described
- Finishes specified by brand, model, and grade — not generic descriptions
- Commencement date trigger defined (substantial completion preferred over fixed date)
- Substantial completion defined with specific certificate of occupancy requirement
- Tenant delay clause has minimum threshold (5+ days) and written notice requirement
- Change order process with cost estimate timeline and approval requirements defined
- Landlord markup on change orders capped at 10% or less
- TI allowance draw process specified (direct pay vs. reimbursement)
- TI allowance expiration date tied to milestones, not lease commencement
- Substitution approval rights requiring written tenant consent
- Inspection rights at defined construction milestones
- Punch-list process and period defined (typically 30–60 days post-substantial completion)
- Remedies for landlord delay (rent abatement, self-help, termination right)
- Lien waiver requirements from all contractors and subcontractors
- Insurance requirements for construction period specified
- Building permit responsibility assigned (typically landlord for core/shell, tenant for TI)
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Analyze My Lease Free →Frequently Asked Questions
A tenant improvement (TI) allowance is the dollar amount the landlord contributes to construction. A work letter is the legal document governing the entire construction process — including who manages construction, specifications, approval rights, timelines, payment mechanics, and dispute procedures. The TI allowance is typically one clause within the work letter.
Landlords can and do withhold TI draws if you haven't satisfied disbursement conditions — typically AIA billing forms, lien waivers from contractors and subcontractors, and evidence of work in place. Partial non-compliance can stall your entire draw. Work with an owner's rep or construction manager who understands the draw documentation requirements from the start.
Most commercial leases require the tenant to surrender the space in its original condition, which typically means the landlord owns all improvements made to the space. Some leases distinguish between "standard" improvements (which stay) and "specialty" improvements (which must be removed). Clarify removal obligations in the work letter before construction begins — specialty items like server rooms, vaults, or custom millwork can be expensive to remove.
Withhold the final retainage payment until all punch list items are resolved. If items remain unresolved for more than the contractually specified period (typically 30–60 days), use your self-help rights under the work letter to hire your own contractor to complete the work and deduct the cost from rent. Document everything in writing throughout this process.
Rarely. Commercial leases include integration clauses stating that the written lease and its exhibits constitute the entire agreement between the parties. Verbal promises about improvements made during negotiations are extremely difficult to enforce and are almost universally disclaimed by the integration clause. Get every improvement commitment in writing as an exhibit to the lease before signing.
An "as-is" lease means the tenant accepts the space in its current condition with no landlord obligation to improve it. This can be acceptable for second-generation spaces (previously built out for a similar use) where you need minimal work. However, even in as-is deals you should insist on a brief work letter documenting the existing condition with photos, confirming systems are operational, and defining what the landlord will and won't fix.