A customer wants their hardwood floors refinished. The finish is worn, the scratches are obvious, and a few boards have dark stains. It looks like a straightforward sanding job, until you inspect how much wood is actually left.

Before you quote a full refinish, you need to answer two questions: how much usable wood remains, and how much would this job require you to remove? That assessment can help you avoid turning a worn floor into a replacement project.

Start With the Floor’s Construction

Solid and engineered hardwood require different assessments.

With tongue-and-groove solid flooring, pay attention to the wood remaining above the tongue and groove. The board’s full thickness is not all available for sanding.

Engineered flooring has a hardwood surface layer over a supporting core. A thick overall board does not necessarily have a thick hardwood wear layer. Some engineered products can be sanded; others have surface layers too thin for a full refinish.

Check the Remaining Wood, Not Just the Floor’s Age

A floor’s age or reported number of refinishes does not tell you enough to approve another sanding. Treat that history as a starting point for inspection.

Look for an accessible cross-section at a floor register, threshold, or exposed board end. For solid tongue-and-groove flooring, inspect the distance from the surface to the tongue. For engineered flooring, identify the actual hardwood layer separately from the core.

The NWFA’s Sand and Finish Guidelines advise against sanding when the remaining wear thickness is generally less than 3/32 inch. That is a screening guideline, not a guarantee that every floor above it can be sanded. The same guidance cautions that measuring down to the tongue can misrepresent the usable wear layer on engineered flooring.

Inspect several locations where access allows. Record what you can verify and identify areas where the remaining thickness is uncertain. If you cannot establish that enough usable wood remains, resolve that uncertainty before committing to a full sanding.

Flag Areas That Need a Closer Look

During your walkthrough, mark areas that could affect the scope:

• Exposed fasteners or visible tongue-and-groove components
• Cracked, splintered, or unusually fragile board edges
• Uneven surfaces, previous sanding depressions, or pronounced texture
• Deep scratches, stains, and areas of moisture damage
• Repairs or additions that may have different flooring construction

These observations warrant further assessment; no single visual clue should replace checking the floor’s construction and remaining wood. Photograph questionable areas so you can explain them clearly to the customer.

Compare What’s Left With What the Customer Wants

Ask the customer to identify their priorities before you finalize the estimate. Do they want better protection and a more consistent sheen? A different stain color? Every dark mark removed? A textured floor made smooth?

Those requests can involve very different scopes. Bona cautions that aggressive sanding on thin wear layers can remove excessive material quickly. Avoid assuming that a more powerful machine or a different abrasive will make a marginal floor suitable for sanding.

For example, if a customer wants a deep gouge completely removed, assess that specific area before promising a flawless result. Consider whether retaining the mark or replacing the affected board would be a more appropriate option.

Consider Alternatives to a Full Refinish

Selective board replacement: If damage is concentrated in a few boards, investigate replacement availability and how the repair would blend with the surrounding floor. Assess the remaining floor independently before proposing any sanding as part of the repair.

Full replacement: If you cannot establish a suitable refinishing or maintenance approach, explain replacement options rather than promise an outcome you cannot support.

Put the Assessment in the Estimate

Include the floor type, inspection locations, measurements, questionable areas, and the result the customer has agreed to. Specify whether the proposal is for recoating, sanding and refinishing, repair, or replacement.

Where inspection access is limited, explain what additional assessment is needed and how unexpected findings will be handled before work proceeds.

Need help choosing abrasives, equipment, or a finish system for your next project? Contact City Floor Supply to discuss your options. Bring your flooring details and jobsite findings so our team can help you select products for the scope you have assessed.