8 Questions to Ask Windows, Siding & Insulation Before Hiring

Questions to Ask Windows, Siding & Insulation

Updated November 6, 2026

What Should You Ask Window, Siding, Glazing and Insulation Contractors?

Ask for the license number, insurance certificates and a written contract, then ask who runs the job, who pulls permits and what the warranty covers. For this trade, also ask: Are these full-frame or insert windows? Typical lead time is several weeks, due to custom order lead times.

Updated November 6, 2026 · Source: construction.broker planning guide (our own assumptions, not survey data); always compare written bids.

The Questions

What is your license number, and which state or city issued it?
Can you send a current certificate of liability insurance and proof of workers’ compensation?
Will the contract list the scope, materials, price, start and finish dates and payment schedule?
Who pulls the permits, and are they included in the price?
Who will run the job day to day, and will you use subcontractors?
What warranty do you give on labor, in writing?
Are these full-frame or insert windows?
What are the manufacturer and installation warranties?

Good to Know

Be wary of limited-time discounts that require signing today.
Federal cooling-off rules may cover some in-home sales; ask for the cancellation form.

Cost and Timing

As a planning figure, expect often priced per window or per square foot of wall. Typical lead time is several weeks, due to custom order lead times. These are our own assumptions, so compare written bids.

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