Interior Material Choices Contractor: Questions to Ask

What to take away

Questions about credentials

Start here, because the answers are checkable. Ask for the business license, the insurance certificate with your project named, and any trade certification relevant to the work. For renovation that disturbs paint in pre-1978 housing, ask whether the firm is certified under EPA's Renovation, Repair and Painting (RRP) Rule as a Lead-Safe Certified Firm; a general contractor license is not a substitute.

Ask a second question that most homeowners skip: who is actually on site each day, and are they employees or subcontractors? Certification attaches to firms and to trained individuals, so a certified company sending an uncertified crew is a real risk.

Then ask what happens if testing finds a hazard. A contractor who says "we would stop and bring in an abatement firm" is describing the correct answer. One who says "we handle that ourselves" needs to prove it with paperwork.

For material credentials, ask for TSCA Title VI compliance for composite wood and Green Seal GS-11 for paint. TSCA Title VI formaldehyde limits are 0.05 ppm for hardwood plywood, 0.09 ppm for particleboard, and 0.11 ppm for MDF. For flooring, FloorScore or CRI Green Label Plus covers many resilient and carpet products.

Questions about dust, containment and lead

Lead work is the area where a bad answer is most expensive. Paint disturbed by sanding, scraping or demolition produces dust, and EPA sets the hazard standards and clearance levels for lead in paint, dust and soil that define when a surface counts as a hazard and when a cleaned area passes.

Ask specifically: how will you contain the work area, will you use HEPA vacuums, how will waste leave the house, and will a clearance test be performed at the end? CDC's summary of lead in paint and how exposure happens at home is worth reading before this conversation so you can tell a serious answer from a reassuring one.

If children under six or anyone pregnant lives in the house, say so explicitly and ask how the schedule will protect them. Relocation during dusty phases is a normal answer, not an alarmist one.

For dust control, consider prefinished engineered hardwood, porcelain tile, or sheet linoleum instead of site-finished wood. Porcelain tile typically has water absorption at or below 0.5 percent and a DCOF of 0.42 or higher for wet areas. Engineered hardwood wear layers commonly range from 2 mm to 4 mm.

Questions about products and documentation

Put the winning answers into the contract as named products. "Low VOC adhesive" in a contract means whatever is in the van on the day.

For floors, name the wear layer and the adhesive. A 2 mm to 4 mm wear layer suits most homes. For tile, specify porcelain with water absorption at or below 0.5 percent, a DCOF of 0.42 or higher in wet rooms, and epoxy grout. For cabinets, specify TSCA Title VI plywood at 0.05 ppm or particleboard at 0.09 ppm.

Questions about the finish line

Define completion before work starts. Ask what surfaces will be cleaned, whether HVAC filters will be replaced, whether ducts were sealed during the work, and what the punch list process is. Ask how long the contractor guarantees their labor as distinct from the manufacturer's material warranty, and get both in writing.

Set your shortlist against the planning steps in our pre-project guide to interior materials, and read the answers alongside the failures that recur on interior jobs. A contractor whose answers anticipate those failures is usually the one who has seen them.

For wood finishes, choose water-based polyurethane or hardwax oil. Typical VOC limits are 50 g/L for flat paint and 100 g/L for non-flat paint under Green Seal GS-11 or SCAQMD Rule 1113. For stone, use a breathable impregnating sealer and avoid solvent-based sealers in occupied rooms.

Common questions