Front-load washers spin a heavy, wet load fast, and the floor under them becomes part of the machine. A floor that's level and stiff absorbs the motion. A floor that tilts or flexes gives some of it back, and the result is the familiar thumping, buzzing or "walking" washer. In a city where laundry ends up on wood-framed upper floors, in basement corners and inside stacked closets, the floor deserves as much attention as the hookups.
What manufacturers ask for
Whirlpool (commercial front-load washer)
The installation instructions for Whirlpool's CHW9160GW front-load washer call for a level floor with no more than 1 inch of slope under the entire washer, and a sturdy, solid floor that can carry a total weight of 400 pounds with water and laundry. Installing on soft floor surfaces such as carpet is not recommended. That's a commercial model, and residential models list their own weight figures, so check your guide. The principles are the same.
Maytag
Maytag's leveling page explains the reasoning: these high-spin speed washers require sturdy floors, and flooring that flexes or is uneven can add to noise and vibration. It offers a useful test (vibration you can feel in the floor from across the room can be a sign of a flexing floor) and a common remedy: securing a 3/4-inch piece of plywood to the floor under the washer and dryer may reduce noise and vibration. Whirlpool's own leveling page says the same.
LG
LG's vibration troubleshooting page says the washer must be level and installed on level, solid flooring with properly adjusted feet. All four leveling feet should be firmly and evenly in contact with the floor, and the lock nuts on all four should be tight after any adjustment.
Why the floor matters so much
- •Spin forces add up. No load is perfectly balanced. At high spin speeds, a small imbalance becomes a strong, rapid push against the floor.
- •Flex amplifies motion. A springy floor moves with the washer, and the two can reinforce each other. That's why the shaking can seem far worse than the load explains.
- •Slope loads the feet unevenly. On a tilted floor, the drum's motion isn't centered and one or two feet carry more of the weight.
- •Soft surfaces shift. Carpet and foam-backed flooring let the feet sink and move, so the washer never stays level.
DC floors and where laundry ends up
- •Upper-floor closets in rowhouses. Renovations often move laundry upstairs, near the bedrooms. Those floors are wood joists, and a washer near the middle of a long span will feel more flex than one near a bearing wall.
- •Basements. A concrete slab is stiff, which is good for vibration. But older basement floors can slope toward a drain, which may push past the 1-inch limit across the washer's footprint.
- •Stacked units in condos. Compact stacked sets in closets are common in DC apartments. Stacking puts the dryer's weight and the combined height on the same small footprint, which makes level and stable feet even more important. See washer and dryer stacking kit requirements.
- •Neighbors below. In a condo or a converted rowhouse with units stacked on top of each other, vibration that's merely annoying to you can be loud in the unit below. Building rules sometimes address washer installation, so check them.
How to check a floor
- Lay a level across the spot where the washer will sit, side to side and then front to back. Measure any gap under the low end to estimate the slope across the footprint.
- Figure out what's underneath. A slab is very stiff. A wood floor over a basement, crawlspace or another room flexes more, especially mid-span.
- Stand where the washer will go and bounce gently on your heels. If you feel the floor give or hear something rattle, it's flexible.
- After installation, rock the washer diagonally, corner to corner, as Maytag and LG describe. Any teetering means a foot isn't carrying its share.
- Confirm the lock nuts on all four feet are tightened against the cabinet.
- During a high-speed spin, stand across the room. If you can feel the floor vibrate there, Maytag treats that as a sign the floor is flexing.
What an inadequate floor causes
- •Loud thumping or a buzzing floor during spins.
- •A washer that walks out of position and stretches its hoses or power cord.
- •Repeated pauses or slow spins as the washer detects imbalance and tries to correct it.
- •Faster wear on the shock absorbers, springs and drum bearings.
Fixes, from simple to structural
- •Level and lock. Adjust the feet so all four touch firmly, then tighten the lock nuts. It's the first thing to try, and often the only fix needed.
- •Remove the soft layer. If the washer is on carpet or a foam-backed floor, move it to a hard surface.
- •Add plywood. Maytag and Whirlpool both suggest securing 3/4-inch plywood under the washer and dryer to reduce vibration on a floor that flexes.
- •Reinforce the framing. If the floor still moves noticeably, a contractor or structural engineer can assess the joists and whether blocking or added framing would help. Don't cut or notch joists yourself.
- •Move the laundry. Relocating to a stiffer spot means new water lines, a drain and possibly a new circuit, which are jobs for a licensed plumber and electrician. In DC, those trade permits are obtained by master-licensed professionals, per the Department of Buildings Instant Permits page.
Drainage matters as much as the floor. See washer standpipe height for those specs.
When the floor isn't the problem
If the washer is level, all four feet are locked, the floor is solid and it still shakes, the cause is likely inside the machine: worn shock absorbers or suspension springs, a failing bearing, or shipping bolts that were never removed from a new unit. Our washer repair technicians can check the suspension and drum, and if the dryer stacked on top is part of the noise, our dryer repair service covers that too.
Sources
- •Whirlpool: CHW9160GW commercial front-load washer installation instructions (1-inch maximum slope; 400-pound sturdy floor; no soft surfaces)
- •Maytag: Leveling a Front Load Washer (sturdy floors; flex test; 3/4-inch plywood; corner rocking; lock nuts)
- •Whirlpool: Leveling a Front Load Washer (sturdy floors; 3/4-inch plywood)
- •LG: Washer troubleshooting vibration issues (level, solid flooring; feet and lock nuts; corner test)