Before you can renovate a co-op or condo in New York City, you almost always need your building's approval through an alteration agreement — a contract between you, the building, and often your contractor that governs what work is allowed, who carries the liability, and how the project must be run. For a complete, professionally prepared package, approval typically takes 4 to 8 weeks. This guide explains what goes into the package, how co-op and condo approval differ, and how to get through the process without triggering a second round of review.
What Is an Alteration Agreement?
An alteration agreement (sometimes called an "alt agreement") is the building's rulebook for your renovation, made binding. It spells out permitted work hours, insurance requirements, the protection of common areas, rules about plumbing and structural changes, penalties for overruns, and the building's right to inspect. Signing it is a precondition for starting work, and violating it can halt your project. Nearly every co-op requires one; most condos do as well, especially for anything beyond paint and finishes.
Co-op vs. Condo: How Approval Differs
The ownership structure drives the difference. In a co-op, you own shares in a corporation that owns the building and hold a proprietary lease on your unit, which gives the board broad authority over what you may alter. Co-op approval is typically the more demanding of the two — more documentation, stricter rules, and sometimes a board interview or a detailed review of your contractor.
In a condo, you hold title to your individual unit, so the board's authority is narrower and approval is often faster and lighter. That said, most condos still require an alteration agreement, proof of insurance, and review of any work that touches plumbing, gas, structure, or the building's systems. The prewar co-ops of the Upper West Side and Upper East Side tend to sit at the stricter end of the spectrum — a context we cover in our prewar apartment renovation guide.
What Belongs in a Complete Board Package
The single biggest cause of delay is an incomplete package, which sends you to the back of the queue for another review cycle. A complete submission generally includes:
- The signed alteration agreement itself.
- Stamped architectural plans prepared by a licensed architect or engineer, detailed enough for the building's reviewer to evaluate.
- A detailed scope of work describing exactly what will be done.
- Contractor documentation — license, and a certificate of insurance naming the building, the managing agent, and often the board as additional insured.
- Insurance coverage — general liability and workers' compensation at the limits the building requires.
- An engineer's letter when the work is structural, or when a bathroom or kitchen ("wet" area) sits over a neighbor's living space ("dry" area).
In parallel with the board package, most full renovations require permits from the NYC Department of Buildings. We file board and DOB approvals concurrently so the timelines overlap — one of the levers that keeps the overall renovation timeline from stretching.
The Approval Timeline
For a complete package, expect roughly four to eight weeks to a decision. The variables that extend it are predictable: boards that meet only once a month, buildings that route plans through an outside architect or engineer for review, and the back-and-forth that an incomplete or ambiguous package invites. Summer and holiday periods, when board members travel, can also slow things down. Building this window into your plan from the start prevents the scramble of a renovation that is ready to begin but waiting on a signature.
Why Packages Get Delayed — and How to Avoid It
- Incomplete documentation. A missing insurance endorsement or an unsigned page restarts the clock. A thorough first submission is the best protection.
- Wet-over-dry conflicts. Moving a bathroom or kitchen over a neighbor's bedroom or living room frequently requires waterproofing details and an engineer's sign-off, and some buildings prohibit it outright.
- Insurance shortfalls. Contractors whose coverage limits or additional-insured language do not match the building's requirements are a common stumbling block.
- Plans that ignore building rules. Work hours, noise limits, and restrictions on altering structure or façade are non-negotiable; designing within them from day one avoids forced revisions.
How a Full-Service Team Handles This for You
Navigating board approval is one of the clearest advantages of working with a single team that manages design, approvals, and construction together rather than coordinating a separate architect, expediter, and contractor yourself. A firm that has worked in your building — or in similar prewar co-ops — knows the managing agent, understands the board's particular requirements, and prepares a package the reviewer recognizes as complete. That relationship and experience is a core reason the design-build approach moves through approvals faster.
At Knockout Renovation, we have shepherded renovations through co-op and condo boards across Manhattan and Brooklyn for more than 30 years. We prepare the alteration agreement package, coordinate with your managing agent and the building's engineer, file the necessary DOB permits, and carry the project all the way through final building sign-off. If you are planning a renovation and want help getting it approved cleanly the first time, we would be glad to guide you through it.
Frequently Asked Questions
Do I need board approval to renovate my NYC co-op or condo?
Almost always, yes. Nearly every NYC co-op and most condos require an approved alteration agreement before any renovation work begins — even for cosmetic projects in many buildings. The agreement governs what work is permitted, the contractor's insurance and liability, work hours, and how the project must be carried out.
How long does NYC board approval take?
Once you submit a complete alteration agreement package, most boards respond in 4 to 8 weeks. Buildings that require review by an outside architect or engineer, or that only convene monthly, can take longer. The most reliable way to keep approval on schedule is to submit a complete, professionally prepared package the first time.
What is the difference between co-op and condo renovation approval?
Co-ops generally have stricter, more involved approval because shareholders own shares in a corporation that owns the building, giving the board broad authority over alterations. Condo owners hold title to their units, so condo approval is often lighter and faster — but most condos still require an alteration agreement, insurance, and plan review, particularly for work affecting plumbing, gas, or structure.
What documents go into an alteration agreement package?
A typical package includes the signed alteration agreement, stamped architectural plans, a detailed scope of work, the contractor's license and certificate of insurance naming the building and managing agent as additional insured, workers' compensation and liability coverage, and often an engineer's letter for structural or wet-over-dry work. DOB permits are filed in parallel.
Can a co-op or condo board reject my renovation plans?
Yes. Boards can reject or require changes to plans that affect the building's structure, move 'wet' areas like bathrooms over a neighbor's 'dry' rooms, exceed noise or work-hour rules, or lack adequate insurance. A board can also simply require revisions. Designing within the building's rules from the start is the best way to secure a clean approval.