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Unilock Home Additions & ADU: The Sherman Oaks Owner’s Guide
We stock and install Unilock-compatible hardscape systems for home additions and ADU projects in Sherman Oaks, with typical installed pricing from $45,000 to $130,000 for additions and $90,000 to $220,000 for detached ADUs. Most homeowners who call us about a failing Unilock element notice it during the transition between the existing structure and the new build, where settling, drainage, or thermal expansion has stressed the interlocking paver system. We carry Beacon Hill Flagstone, Bristol Valley, and Copthorne series inventory on our trucks, and we can usually match your existing Unilock color and texture within a day.
The failure usually shows up as shifting at the threshold where the original foundation meets the addition slab, or as water pooling against the ADU entry after the first heavy winter rain. In Sherman Oaks, we see this most often on properties south of Ventura Boulevard where the clay-heavy soil holds moisture and the freeze-thaw cycle, mild as it is, still moves pavers a few millimeters each season. That movement compounds if the original installer skipped the open-graded base layer or used the wrong edge restraint for a load-bearing walkway.
Which Unilock Models This Applies To
Unilock organizes its residential line into Series 3000, Series 4000, and the premium U-Cara and Richcliff collections. For home additions and ADUs in Sherman Oaks, we most commonly match Beacon Hill Flagstone for its 80mm thickness and the three-size random bundle pattern that blends with 1990s-era hardscape. Bristol Valley works when the existing patio uses the 60mm Arbel or Umbriano lines, though the joint spacing differs by 3mm and that gap matters for sand-lock stability.
To identify your exact match, look for the manufacturing date stamp on the paver edge, usually a two-digit year code plus plant identifier. The color name is cast into the mold, not surface-applied, so fading won’t obscure it. OEM Unilock from the original production run guarantees color match; aftermarket equivalents from Belgard or Techo-Bloc can come within one shade but rarely closer. We stock both options because some Sherman Oaks HOAs require documented Unilock origin for hardscape repairs, while others accept equivalent ASTM C936 compliance. If your addition ties into a U-Cara fascia system, the wall units are proprietary and only Unilock manufactures the clip-and-pin connectors.
Signs Your Unilock Home Additions & ADU Is Failing

- Stepping or rocking underfoot at the addition threshold. This means the bedding sand has migrated through a failed joint, leaving a void. In Sherman Oaks, we find this where the original contractor used masonry sand instead of polymeric joint sand, which washes out in the first season of irrigation overspray.
- Water pooling against the ADU foundation after rain. The interlock has lost its pitch, usually because the open-graded base compacted unevenly or the edge restraint popped. Pooling water in our climate breeds efflorescence on the wall and can wick into the sill plate.
- Chipped corners on pavers within 18 inches of the structure. These are stress fractures from differential settlement between the existing foundation and the new addition footing. The gap is often invisible until the paver fails.
- Weeds growing through joints that were supposedly sealed. Polymeric sand breaks down when installed over damp substrate or when the joint depth is less than 1 inch. Sherman Oaks yards with heavy ficus root intrusion see this accelerated.
- White powder staining on the paver surface. Efflorescence is mineral migration from the concrete base, common in new Unilock installations but persistent in older ones only if moisture is trapped. It signals a drainage failure beneath the system.
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AfterReplacement Cost & What’s Included
| Scope | Price Range in Sherman Oaks |
|---|---|
| Home Addition (full build, Unilock hardscape included) | $45,000 - $130,000 |
| Detached ADU Construction | $90,000 - $220,000 |
| Garage Conversion to ADU | $30,000 - $80,000 |
| Paver Patio Repair/Replacement (isolated) | $3,500 - $11,000 |
| Driveway Paver Installation/Repair | $7,000 - $18,000 |
The range depends on three factors we itemize in every written quote: square footage of the affected area, whether the base needs reconstruction or just re-leveling, and whether your Unilock color is a current production run or requires special-order from the Ontario, CA distribution yard. Our price includes removal and disposal of failed material, re-compaction of the open-graded base to 98% Proctor density, new bedding sand, paver installation with Unilock-recommended joint sand, and edge restraint anchoring. Under Clause 1 of the Haven Standard, that price is fixed before we start. The 365-Day Done Right Promise covers settling, joint failure, or color mismatch we should have caught.
We also source KraftMaid cabinetry, Cambria and Silestone countertops for the interior finish of your addition or ADU, which lets us quote the full project without the markup of multiple subcontractor layers.
DIY or Call Us?

What you can safely check: lift one paver at the failure edge and measure the joint depth and base thickness. If the sand bed is less than 1 inch or the base is visibly saturated, you’ve found the problem. Document it with photos, the same way we do on every visit.
Where DIY goes wrong: re-leveling pavers without re-compacting the base guarantees recurrence within two seasons. The plate compactor rental is straightforward, but judging the moisture content of the aggregate base takes experience, and over-compaction fractures the material while under-compaction leaves voids. More critically, any work that alters drainage against your foundation or ADU slab can redirect water toward the structure, and in Sherman Oaks that risks mold remediation costs that dwarf the original paver repair. We don’t recommend homeowners operate compaction equipment within 18 inches of a stucco wall, the vibration can crack the weep screed.
Call (213) 221-0788 and we’ll schedule a free estimate. We bring paver samples, measure the base, and deliver a written price before we leave.
FAQs
Properly installed Unilock with open-graded base and polymeric joints lasts 25 to 30 years in our climate, though the surface color fades to a softer tone after 10 to 15 years of UV exposure. The freeze-thaw cycle here is mild, so spalling is rare; base failure from root intrusion or irrigation overspray is the more common limit. Call (213) 221-0788 for an exact quote on extending or repairing your system, estimates are free.
Individual pavers can be lifted and re-laid if the base is sound and the color match is acceptable, but we only recommend this for failures affecting less than 10 percent of the area. Widespread joint sand loss or base saturation means the system has failed as an assembly, and spot repairs will telegraph through within a year. We document the extent with photos before recommending either approach. Call (213) 221-0788 to schedule an evaluation.
Isolated paver repairs run 1 to 3 days; full hardscape integration with a home addition or ADU follows the construction schedule, typically 8 to 16 weeks for an addition and 12 to 24 weeks for a detached ADU. Weather delays in Sherman Oaks are minimal, though we avoid pours and compaction during Santa Ana wind events when dust control is impossible. The written schedule we provide includes these contingencies. Call (213) 221-0788 for project-specific timing.
We stock Beacon Hill Flagstone in the Sierra and Almond Grove colorways, plus Bristol Valley in New York Blend and Copthorne in Basalt, on our Sherman Oaks trucks. Other colors and the U-Cara wall system typically ship from Unilock’s Ontario distribution center within 3 to 5 business days. We don’t start removal until material is on-site, so there’s no downtime. Call (213) 221-0788 to confirm availability for your specific match.
Rowan Construction Group Sherman Oaks is an independent contractor and is not affiliated with, endorsed by, or a warranty service provider for Unilock Corporation. We install Unilock products according to manufacturer specifications and our own Haven Standard protocols.
Grant Rowan grew up in Los Angeles and has spent the better part of three decades doing construction work across the San Fernando Valley. He studied construction technology at Los Angeles Valley College in Valley Glen, where he learned to read structural drawings before he ever swung a framing hammer on a paid job. In Sherman Oaks, he’s handled projects near the Galleria corridor and the residential streets off Ventura Boulevard, and he stays hands-on enough that he can tell when a subfloor isn’t sitting right just by walking across it. Measure twice, write it down, then build it.
Written by Grant Rowan, Owner, Rowan Construction Group Sherman Oaks at Rowan Construction Group Sherman Oaks, serving Sherman Oaks and nearby areas.







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