How to Read a Houston Commercial Lease: NNN, CAM and the Clauses That Cost Tenants Money

Start with the lease type, because it determines what the quoted rate actually includes. A gross lease bundles operating costs into one number. A modified gross lease splits them, usually with the landlord covering taxes and insurance and the tenant covering utilities and janitorial. A triple net—NNN—lease quotes base rent only, and the tenant pays a proportionate share of property taxes, building insurance and common area maintenance on top. In Houston commercial real estate, NNN is the default for retail and industrial, and increasingly common in office.

Then find the load factor, which is where quoted office rates quietly become larger bills. You lease usable square feet—the space inside your walls—but you pay on rentable square feet, which adds your share of lobbies, corridors, restrooms and mechanical rooms. A 12% load factor on 5,000 usable square feet means paying for 5,600. Two buildings quoting the same rate can differ by thousands of dollars a year purely on this. Ask for the load factor in writing and confirm the measurement standard.

CAM is the line item most worth reading slowly. Common area maintenance covers landscaping, parking lot upkeep, security, management fees and shared utilities—legitimate costs. The problems come from what gets slipped in: capital improvements amortized as operating expenses, the landlord’s own administrative overhead, and costs for parts of a portfolio your building does not use. Push for an exclusions list, an audit right, and a cap on controllable CAM increases—typically 3 to 5% annually, cumulative. Landlords resist the cap and frequently concede it.

Understand the difference between base year and expense stops in office deals. A base year sets your expense obligation at the actual operating cost in year one, with you paying increases above that. If the base year is artificially low—a building that was half empty, or one where taxes had not yet been reassessed after a sale—your increases start immediately and compound. In Harris County, where reassessment after a sale is routine, an unadjusted base year is a genuine trap.

Read the escalation clause carefully. Fixed annual increases of 2 to 3% are normal and easy to budget. CPI-indexed escalations are less predictable and should carry both a floor and a ceiling. Watch for escalations that apply to the gross rent rather than the base rent, which compounds your operating expense share as well.

Tenant improvement allowances are negotiable and frequently under-negotiated. The allowance is what the landlord contributes toward building out your space, quoted per rentable square foot. What matters as much as the number is who controls the work, who owns the improvements at the end, whether unused allowance can be applied to rent, and whether you must restore the space to its original condition on exit. That last clause—restoration—can be a five-figure surprise years later. Negotiate it at signing, when you have leverage.

Check personal guaranty and assignment language before anything else if you are a small business. A full personal guaranty puts your house behind the lease. A good-guy clause, which limits personal exposure to the period you actually occupy provided you give proper notice and leave the space clean, is a far better structure and is commonly available. On assignment and subletting, insist that landlord consent is not unreasonably withheld, otherwise selling your business later becomes the landlord’s decision.

In Kingwood and the Lake Houston corridor, the practical considerations shift. Inventory is tighter, so leverage on rate is limited, but landlords are often more flexible on term length and improvement allowance because they value a stable local tenant. Retail space along the corridor tends toward NNN with percentage rent on larger deals, while office space in Kingwood and medical office space more often run modified gross with a base year.

Medical deals carry their own layer. Beyond the standard terms, verify plumbing and electrical capacity for your equipment, confirm the building permits medical use and that parking ratios support patient volume, check ADA compliance in the common areas, and address biohazard waste handling. A medical build-out costs multiples of a general office build-out, which makes the improvement allowance and the term length far more consequential.

One honest caveat: the landlord’s leasing agent works for the landlord. They may be pleasant, responsive and genuinely helpful, and they still have a fiduciary duty pointed away from you. Tenant representation costs you nothing in most Houston deals—the commission is paid from the landlord’s budget either way—so going unrepresented does not save money, it just removes an advocate. If you also own or manage property, our commercial property management page covers the other side of the same document.