Contractor Warranty Clause: What to Include and What to Exclude (2026)

Your warranty clause is one of the most important (and most ignored) sections of a contractor proposal. Too broad and you're liable for things that aren't your fault. Too narrow and you lose bids to contractors who offer better terms. Here's the right balance.

What to cover in your warranty

• Workmanship warranty: Your work will be free from defects due to your installation. Typical: 1–2 years for most trades.
• Materials warranty: Materials you supply and install will perform as specified. Usually pass-through from manufacturer — reference the manufacturer's warranty by name.
• Response commitment: "We will respond to warranty claims within [X business days]" — this matters more to clients than the warranty length.

What to exclude (critical)

• Client-supplied materials (you install it, but their material fails — not your fault)
• Normal wear and tear
• Damage from subsequent contractors working on the same area
• Damage from client misuse, modification, or failure to maintain
• Damage from extreme weather events (acts of God)
• Pre-existing conditions discovered after work starts (document these at the start)

Typical warranty durations by trade

• New construction: 1 year workmanship (most states mandate by law)
• Roofing: 1–2 years workmanship; 20–50 years manufacturer on materials
• Painting: 1–3 years on exterior; 1–2 years interior
• Plumbing and HVAC installation: 1 year workmanship
• Foundation repair: often a transferable lifetime warranty (competitive differentiator)
• Landscaping and plants: often 1 year on plants, 90 days on hardscape

State-mandated warranties

Most states have implied warranty laws that override your contract. In many states, new residential construction has a statutory 1-year workmanship warranty, 2-year systems warranty, and 10-year structural warranty — whether you include it in your contract or not. Check your state's contractor licensing board for specifics. Your contract cannot waive a statutory warranty.

Sample warranty clause

Contractor warrants all workmanship against defects for one (1) year from the date of substantial completion. This warranty does not cover normal wear and tear, client-supplied materials, damage caused by subsequent modifications or other contractors, or damage resulting from extreme weather or client misuse. Manufacturer warranties on materials are passed through to the client and are separate from this workmanship warranty.

ConstruMate includes a warranty section in every proposal — pre-filled with standard language you can customize. Try it free.

Add a professional warranty clause to your next proposal →