"Are you licensed and insured, and do you have a manufacturer certification for this product?"

Why it matters: Some siding manufacturers (James Hardie, for example) have contractor certification programs that require installation training. A certified installer can offer enhanced warranties that others cannot.

"Are you tearing off the old siding or installing over it?"

Why it matters: Installing new siding over old adds cost savings upfront but hides what is underneath. Rotted sheathing, damaged housewrap, pest damage, and moisture problems all stay hidden until they are much worse.

"What housewrap are you installing, and how do you handle laps and seams?"

Why it matters: Housewrap is the moisture barrier between your sheathing and your siding. It needs to be lapped correctly (upper layer over lower, like shingles), taped at seams, and flashed properly at penetrations.

"How do you flash windows, doors, and other penetrations?"

Why it matters: Every window, door, outlet, light fixture, and hose bib that penetrates the siding plane is a potential water entry point. Each one needs to be properly flashed and sealed.

"Will you inspect and repair the sheathing before installing new siding?"

Why it matters: After tear-off, the contractor should inspect every panel of sheathing for rot, moisture damage, or structural compromise. Any damaged panels should be replaced before new siding goes on.

"How do you handle nailing gauge and nail pattern for this product?"

Why it matters: Vinyl siding in particular must be nailed loosely to allow for expansion and contraction. Nails driven too tight prevent movement and cause buckling.

"Are J-channel, trim, and corner pieces included in the quote?"

Why it matters: J-channel (the trim that frames windows and doors), corner trim pieces, and soffit and fascia work are often quoted separately or left out entirely. These are not optional.

"How do you handle color matching between material batches?"

Why it matters: Siding panels from different production runs can have subtle color differences. If you need to do a repair in three years and the original batch is discontinued, matching becomes a problem.

"What is the ventilation plan behind the siding?"

Why it matters: Some siding products (especially fiber cement) benefit from a rainscreen gap between the siding and the housewrap that allows air circulation and moisture to drain. This is not always required, but it is a quality differentiator.

"What does the warranty cover, and for how long?"

Why it matters: Siding has two warranties: the product warranty from the manufacturer (typically 25-50 years for quality products) and the installation warranty from the contractor (typically 1-5 years). Know what each covers.

"Is a permit required for this project?"

Why it matters: Full siding replacement requires a permit in many jurisdictions. The permit triggers an inspection that catches installation problems.

"What is the payment schedule?"

Why it matters: Materials are typically ordered and paid for before installation begins. A reasonable structure: deposit at signing, materials payment on delivery, balance on completion.