Floor, stair and tile repair in Los Angeles

Around half the housing in the City of LA was built before 1960, and the county’s median home dates to the mid-sixties. Floors from each era fail in their own way.

Raised floors over a crawlspace

Bungalows from the twenties sit on a stem wall with interior posts on separate piers that settle at their own pace. The subfloor is usually 1x6 or 1x8 boards laid diagonally over joists at sixteen inches, and board subfloor flexes far more than plywood. Two board ends rubbing at a butt joint is the most common squeak in this housing. The other is the subfloor nail moving in the joist, where the shank has worn its hole oversize. That one ticks once per step and travels with you across the room. The two get fixed from opposite sides, a subfloor nail shimmed or screwed off from below and finish flooring moving on the subfloor handled from above.

Post-war slab houses

Slab took over the tract housing from about the mid-fifties on. A 1948 or 1952 house in Van Nuys or Lakewood is as likely to be raised as slab, so look for a crawlspace hatch before you assume. On a slab there are no joists to squeak. A noise there is a floating floor over an uneven slab, loose underlayment, or adhesive that has let go. Those slabs predate vapor retarders, so moisture pushes up through them all winter. Original tile here is often mudset over wire lath, which doesn’t fail on its own, so a cracked tile is usually a slab crack telegraphing through.

Apartments and condos with a concrete topping

Seventies and eighties buildings across Palms, Koreatown and North Hollywood usually have plywood over the joists and an inch of soft, chalky gypsum concrete on top for sound. Drive a squeak screw through gypcrete and you blow a crater around the head instead of pulling anything tight. The noise is the plywood underneath, and reaching it means cutting out topping that forms part of a rated assembly between two units.

On a raised house the crawlspace answers more than an hour upstairs does. Joist size and spacing, damp ground, split joists, and whether the squeak can be reached from below at all. One person walking while another listens from underneath answers in five minutes what an hour upstairs won’t. It takes two people, and it is easy to skip. On slab, a square of clear plastic taped down and read two days later says whether moisture will kill a glue-down repair.

Squeaks are also directional, so the floor gets walked both ways with blue tape on every noise. A straightedge over the tape separates a squeak from a dip, and three-eighths of an inch of dip in six feet is a joist problem wearing flooring.

Floating floors have to float

Laminate and most vinyl plank are laid loose with a gap around the perimeter so the field can move. When a plank lifts at the wall, or the floor peaks in a ridge across a room, that gap has been caulked solid or the baseboard nailed through the plank. Reopening it means shoe molding off around the whole room. Locking profiles are proprietary too, so a spare plank from the install often decides whether a repair is possible.

What Santa Anas and the rainy season do

Santa Ana events in the fall drop indoor humidity into the teens for days. Strip flooring shrinks, seams open, and squeaks that were silent all summer turn up in October sounding sudden. December rain swells the boards back, so filling a gap at either extreme earns a callback four months later. Wait until February and the gap you were going to fill has often closed on its own. Squeaks move with the seasons too, since the nail hole opens up as the boards shrink around the shank, so a floor or a tread silenced in October is worth walking again after the rain.

Cracked and hollow tile

A crack running in a line across several tiles is the substrate moving. One tile with a spider pattern took an impact. Tap the field before anything else. A tile that answers hollow has let go of the bed underneath even if it looks fine, and the tiles around a crack usually answer hollow too, which is what decides whether you’re replacing one tile or six. Mudset tile has to be chiseled out, which is why a single tile in a 1950s bathroom costs what it does. Grout on a repair comes out close and never perfect.

Start where the tread meets the riser. That joint is where most stair squeaks live, and the stringer end gets blamed for it. Old LA stairs were built with triangular glue blocks in that corner, and after ninety years the glue has failed and the blocks are in the dust below. Where the underside is open, new blocks go in from beneath and nothing shows on top. Closed in with plaster, everything happens from above and every fastener has to be hidden.

In hillside houses, when the same three treads squeak every winter and go quiet by summer, the stair is reporting on the foundation under it.

Why a tread swap isn’t a cosmetic job

California caps riser height at 7-3/4 inches and sets tread depth at 10 inches minimum, and inside one flight the tallest riser can’t exceed the shortest by more than three-eighths of an inch. Which is why the retro-tread overlay kits sold as a weekend project are awkward. Half an inch on every tread leaves the landing where it was, so the end risers change height and a long flight can fall out of tolerance.

Kitchens and baths in old LA houses have been re-floored three or four times and the layers are still down there. Fir, a quarter inch of ply, fifties vinyl tile, sheet goods, then whatever you stand on now. Nine-by-nine tile is close to a guarantee of pre-1980, and the black brittle adhesive under it often holds chrysotile when the tile doesn’t.

Cutting, grinding and dry-scraping are what put fiber in the air. Leaving intact material alone and floating a new floor over the top is often the right answer, and it costs less. South Coast AQMD Rule 1403 requires an asbestos survey before renovation or demolition anywhere in the basin, single-family houses included, and unlike the federal rule there is no residential exemption. Above 100 square feet of asbestos-containing material the notification and abatement requirements come in as well. That 100 square foot figure is also the Cal/OSHA registration trigger under Labor Code 6501.5. The license side is separate. Asbestos work goes to a contractor carrying the CSLB asbestos certification, and to a C-22 where the abatement is the job itself. Lifting tile in a pre-1980 house means lab sampling first.

Lead is the other one. The federal RRP rule covers pre-1978 housing and trips at six square feet of painted surface disturbed indoors, which is nothing. Resetting painted baseboard along one room passes it, and so does sanding painted risers. EPA runs that program directly in California, so the firm doing it has to be certified.

California has a narrow exemption that lets some minor work be done without a CSLB contractor license. It is Business and Professions Code section 7048, and every part of it has to hold. The work has to be casual, minor or inconsequential. Labor, materials and everything else added together have to come to less than $1,000. No building permit can be required. And the job can’t be one piece of a larger project, or a bigger job split into smaller contracts to stay under the number. The exemption also drops away for anyone who employs another person to do the work or help with it, or who advertises in a way that might suggest to the public they’re a contractor.

Most squeak fixes, a few replacement planks, a handful of tiles, a threshold or a stair tread land under $1,000. Price is one condition out of several though, so it doesn’t settle the question alone. A subfloor patch is the one to watch, since materials push it toward four figures fast. Past the line sit joist work, leveling a room, cutting into a condo topping, and asbestos removal over 100 square feet. LADBS treats new floor covering as needing no permit while modifying subfloor does, and those jobs get matched with a licensed contractor.

Year built and neighborhood, and whether it is a house, a condo, or an apartment with a unit below. Slab or raised, or if you don’t know, whether there is a crawlspace hatch in a closet floor. What the floor is and roughly when it went in. Whether you still have leftover planks or tiles from the install, since that detail decides more repairs than anything else here.

Put blue tape on every spot and send one wide photo showing all of it. A short video with the sound on, walking the squeak, tells a tradesperson more than a paragraph will. Say when it started, whether it moves with the weather, and whether there has ever been a leak nearby. Send that and you’ll have a firm price before a visit gets scheduled.