Flooring is the finish. The subfloor is the structure, and in Seattle houses built across a century of methods, it is rarely ready for a floating floor without work.
What comes out and how
Carpet and pad. Cut into strips, rolled, pad pulled, tack strip pried, thousands of staples removed. The fastest removal and the most common.
Sheet vinyl and glued vinyl plank. Scraped and the adhesive residue addressed. Older sheet vinyl and its adhesive, in houses built before the 1980s, can contain asbestos; if the age and type suggest it, the installer will tell you and recommend testing before it is disturbed, because that removal is specialized work.
Ceramic and stone tile. Broken out with dust control, thinset ground off, backer board removed. Heavy, loud and the most expensive removal per square foot.
Old laminate and floating floors. Unclicked and carried out quickly if floating; scraped if glued.
Hardwood. Usually left and floated over or refinished unless it is failing. Removal of nailed hardwood is priced after it is seen.
Removal is quoted per square foot by type, and the old floor is hauled away the same day.
Seattle subfloors
Plank subfloors in houses built before about 1950: individual boards that cup, gap and move. Usually overlaid with a thin plywood underlayment layer to create a flat, continuous surface.
Plywood and OSB in post-war and newer houses: generally good, but seams swell with past moisture and panels loosen from the joists over decades. Screwed down, seams sanded, swollen areas replaced.
Concrete slabs in basements, daylight lower levels, garages converted to rooms, and many condos: rarely flat, often damp. Ground and leveled, and moisture-tested before a floor goes down. A vapor barrier is always used.
Particle board underlayment in some 1960s to 1980s houses: swells and crumbles when wet and does not hold fasteners. Replaced where it is damaged.
Flattening
High spots are sanded or ground. Low spots and dips are filled with self-leveling or patching compound feathered to flat. Transitions between rooms where floor heights differ are corrected so the new floor runs continuous. The flatness standard is the flooring manufacturer's, because it is the warranty's condition.
Moisture
Most Seattle houses sit over crawl spaces that run damp from October to May, and the subfloor above them carries that moisture. Slabs wick ground moisture year round. Installers meter the subfloor at the measure and again after tear-out, and on slabs run the test the product requires. High readings mean the floor waits until the cause is handled: a wet crawl space needs drying and a vapor barrier below; a damp slab may need a mitigation coating. Installing over moisture is how floating floors cup, swell and smell within a year, and nobody wants to do the job twice.
Squeaks, soft spots and gaps
With the old floor up, loose panels are screwed to the joists, seams that rub are shimmed or filled, soft spots are cut out and replaced, and gaps around plumbing penetrations that let crawl space air into the house are sealed. This is the moment to fix these things; after the new floor is down, it is too late.
On the quote
Removal by type and square foot, disposal, flattening as identified at the measure, and an allowance or a clear note for what the tear-out might reveal. Anything found beyond the quote is shown to you and priced before it is done.
