If you’ve ever placed a ball on your floor and watched it roll to one corner, you know the frustration of uneven floors. But beyond the annoyance, an uneven subfloor can cause serious problems for any new flooring installation — from gaps and creaking in hardwood to cracking in tile.
At Skyline Flooring, floor leveling is one of our core specialties. We’ve leveled hundreds of subfloors across Sherman Oaks, the San Fernando Valley, and greater Los Angeles. Here’s everything you need to know about when leveling is necessary, what methods we use, and what it costs.
Signs Your Floor Needs Leveling
Not every uneven floor needs professional leveling. Here’s how to tell when it does:
Visible Signs
- Gaps between baseboards and floor — indicates the floor has settled or shifted
- Doors that stick or won’t close properly — the frame has shifted with the floor
- Visible slopes — you can feel the floor tilting when you walk
- Cracks in tile or grout — the subfloor underneath is uneven
- Bouncy or soft spots — subfloor material has deteriorated
- New flooring won’t lay flat — planks rock or have gaps underneath
The Ball Test
Place a tennis ball or marble in the center of the room. If it rolls consistently to one direction, your floor has a slope. A slope greater than 3/16 inch per 10 feet typically requires leveling before new flooring can be installed.
Why LA Homes Are Prone to Uneven Floors
Los Angeles homes face specific conditions that cause subfloor problems:
- Concrete slab foundations (common in post-1950 LA homes) can develop low spots over time due to soil settlement, especially in areas with clay soils like parts of Sherman Oaks and Encino
- Earthquake activity — even minor seismic events cause gradual shifting
- Soil expansion and contraction — LA’s wet/dry cycles cause the soil under slab foundations to move
- Age — homes built in the 1950s-1970s throughout the San Fernando Valley often have subfloors that have settled over 50-70 years
- Water damage — plumbing leaks under slabs can erode supporting soil
- Plywood subfloor deterioration — in raised foundation homes, old plywood can warp, delaminate, or develop soft spots from moisture exposure
Floor Leveling Methods We Use
1. Self-Leveling Compound (Most Common)
Self-leveling compound is a cement-based mixture that we pour over the existing subfloor. It flows into low spots and settles to create a perfectly flat surface using gravity. This is our most commonly used method for concrete slab foundations.
Best for: Concrete slabs with minor to moderate unevenness (up to 1.5 inches), kitchens, living rooms, and open-concept spaces
Process:
- Clean and prime the existing concrete surface
- Mix the self-leveling compound to exact specifications
- Pour and spread evenly across the floor
- The compound flows into low areas and levels itself
- Allow 24-48 hours to cure
- Sand any high spots for a perfectly smooth finish
Cost: $4 – $8 per square foot (depends on depth needed)
2. Plywood Underlayment
For raised foundation homes with wood subfloors, we often install new plywood over the existing subfloor to create a flat, stable surface. This is also used when the existing plywood is warped, soft, or damaged.
Best for: Raised foundation homes, areas with damaged plywood subfloors, rooms where height isn’t a concern
Process:
- Inspect and repair any structural joists
- Remove damaged sections of existing subfloor
- Install new 3/4″ or 1/2″ plywood, shimming as needed to level
- Screw down securely to prevent squeaking
- Sand seams for a smooth transition
Cost: $3 – $6 per square foot
3. Grinding and Patching
For concrete floors with isolated high spots, we use concrete grinders to shave down raised areas and fill low spots with patching compound. This is less invasive than a full self-leveling pour.
Best for: Concrete slabs with minor imperfections, isolated humps or ridges, preparation for thin flooring materials like LVP
Cost: $2 – $4 per square foot
4. Mud Jacking / Slab Jacking (Structural)
For severe settlement issues where the entire slab has dropped, mud jacking involves pumping a grout mixture under the slab to lift it back to level. This is a structural repair that we coordinate with foundation specialists when needed.
Best for: Major slab settlement (2+ inches), structural issues, entire rooms or sections that have sunk
Cost: $5 – $15 per square foot (varies significantly)
What to Expect During the Leveling Process
Timeline
| Project Type | Duration |
|---|---|
| Single room, self-leveling | 1-2 days (including cure time) |
| Multiple rooms, self-leveling | 2-4 days |
| Plywood subfloor installation | 1-3 days |
| Grinding and patching | 1 day |
| Major structural leveling | 3-7 days |
Preparation
- Remove all furniture from the room
- We’ll protect adjacent rooms with dust barriers
- Ensure power outlets are accessible (we need electricity for mixers and grinders)
- Plan for the room to be off-limits during curing (24-48 hours for self-leveling compound)
Dust and Noise
Grinding concrete is dusty and loud. We use industrial dust collection systems and HEPA vacuums to minimize dust spread, but some dust is inevitable. Self-leveling compound is much cleaner and quieter — just the sound of mixing and pouring.
After Leveling
Once the leveled surface has cured, it’s ready for your new flooring installation. The leveling creates the perfect foundation for hardwood flooring installation, tile, LVP, or any other flooring material.
Floor Leveling + New Flooring: The Smart Combo
Most of our leveling projects are done as part of a larger flooring installation. When you combine leveling with new floor installation, you save money because:
- One crew handles both tasks (no scheduling two separate contractors)
- We know exactly what the new flooring requires for subfloor flatness
- Mobilization costs are combined
- The timeline is compressed
Example Combo Project
A recent Sherman Oaks project included:
- Demolition of old tile (400 sq ft)
- Self-leveling compound over the concrete slab
- Engineered white oak installation
- New baseboards
Total timeline: 5 days from demo to walking on new floors.
When Leveling Isn’t Enough
Sometimes what appears to be a leveling issue is actually a structural problem. Signs that you may need more than leveling:
- Cracks wider than 1/4 inch in the concrete slab
- Visible cracks in exterior walls or foundation
- Doors and windows throughout the home are sticking
- The slope is greater than 2 inches across a room
- Water is pooling under or around the foundation
In these cases, we recommend a structural engineer assessment before any flooring work. We can coordinate with trusted local engineers and foundation repair specialists.
DIY vs Professional Floor Leveling
While you can buy self-leveling compound at hardware stores, professional leveling is strongly recommended because:
- Mixing ratios are critical — too thin and it won’t set properly, too thick and it won’t flow into low spots
- Surface preparation matters — the primer and cleaning process determines whether the compound bonds or cracks
- Timing is unforgiving — self-leveling compound begins setting in 15-20 minutes. Large rooms require fast, coordinated pouring
- Thickness limitations — compound can only be poured to specific depths in a single pour. Multiple layers require proper timing
- Moisture testing — concrete slabs often have moisture issues that must be addressed before leveling, or the compound can fail
One bad pour means chipping it all out and starting over — doubling your cost.
Related: Floor Demolition and Replacement Guide
Explore our services: Floor Leveling Services | Floor Demolition And Replacement
Get a Free Floor Assessment
Not sure if your floors need leveling? We offer free in-home assessments. We’ll check your subfloor condition, measure the variance, test for moisture, and tell you exactly what’s needed — whether that’s minor patching, full leveling, or nothing at all.
Schedule your free floor assessment or call (818) 300-2205. We serve Sherman Oaks, Encino, Tarzana, Studio City, Woodland Hills, and 50+ cities across Los Angeles and Ventura counties.
If your existing floors just need cosmetic work rather than leveling, check out our floor restoration and repair services.