How much does a retaining wall cost on Long Island?
Most residential retaining walls fall between $180 and $360 per linear foot installed, including drainage. A typical 50 LF wall runs $12,000 to $20,000. Tiered walls, walls over 4 feet, or walls needing geogrid and engineering run higher. Natural stone is the priciest option at roughly $300 to $500 per linear foot. Try our cost calculator for a quick estimate.
Do I need a permit for a retaining wall?
On Long Island's North Shore, retaining walls over 4 feet tall almost always require a permit, and many villages require an engineer's stamp at that height. Walls under 4 feet generally don't require a permit, but it varies by village. We file the permit as part of the job. Full permit guide here.
How long does a retaining wall last?
A properly built Cambridge or Nicolock block wall with engineered drainage and geogrid should last 40+ years on Long Island. Natural stone, set right, lasts 50+ years easily. Pressure-treated timber walls last 20 to 25 years before replacement. Walls built without proper drainage usually start failing in year 5 to 8.
How long does building a wall actually take?
Most jobs take 4 to 10 working days on site. Larger or tiered walls run longer. Permit review adds 4 to 11 weeks depending on the village or town. Natural stone walls take longer than block due to the hand-fitting.
What materials do you use?
Mostly Cambridge Pavingstones (Pyzique, MaytRx, Olde English) and Nicolock (Olde Greenwich, Stonegate). Natural stone from local Long Island suppliers when the look calls for it. We'll use pressure-treated timber for replacements where the budget requires it, but we usually recommend switching to block.
Cambridge vs Nicolock — which is better?
Both are excellent. Cambridge has slightly more color and pattern variety. Nicolock is manufactured on Long Island (Lindenhurst), so delivery is sometimes faster. Quality-wise they're essentially equal. We pick based on what looks right for the property and what's in stock. Full comparison here.
Can I build it myself?
Under 2 feet on flat ground, a careful homeowner can absolutely DIY. Over 3 feet or holding back any real slope, the engineering and drainage get harder than they look. The cost of a failed wall (your foundation, your neighbor's yard) is usually much more than what you'd save building it yourself.
Why do retaining walls fail?
Eight out of ten failures we see are drainage problems. Water builds up behind a wall that was built without geotextile fabric, clean stone backfill, or a drain pipe to a daylight outlet. Pressure builds, water freezes, the wall pushes out. The other two out of ten are bad base prep or missing geogrid on walls over 4 feet.
Do you handle the permit?
Yes. We file with the town or village, follow up on review, handle any plan revisions. Homeowners don't navigate the permit process.
What's geogrid?
A plastic mesh that extends from between courses of block back into the slope. It mechanically ties the wall to the soil. Required on most walls over 4 feet. Skipping it is the #1 reason walls fail on Long Island. More terms in the glossary.
What towns do you serve?
Long Island's North Shore: Huntington, Centerport, Northport, Cold Spring Harbor, Lloyd Harbor, Oyster Bay, Locust Valley, Glen Cove, Sands Point, Port Washington, Manhasset, Great Neck, Roslyn, Smithtown, Stony Brook, Setauket. Full service area list.
Do you provide written quotes?
Yes. Within 5 business days of a site visit, you get an itemized quote: length, height, material, drainage spec, base prep, geogrid if applicable, permit handling, cap details, warranty terms.
Are you licensed and insured?
Yes. Active home improvement contractor licenses in Suffolk and Nassau, general liability and workers' comp. COI provided before any work begins.
Do you offer a warranty?
Yes, a written workmanship warranty on every wall. We stand behind structural integrity and drainage. Terms are written into every contract.
What time of year is best to build?
April through November is the prime window on Long Island. We can build into early December if weather cooperates. Mid-December through March is too cold for proper compaction and adhesive curing. Spring is the busiest time, so book early for a summer install.
Will a retaining wall increase my home value?
A well-built wall that solves a real grade or drainage problem typically adds 100 to 150 percent of its cost in property value. A purely decorative wall is closer to 60 to 80 percent. A failing wall is a negative on the inspection report and can scare buyers off entirely.
What happens if my wall fails after the warranty?
If we built it, we'll come look at it regardless. Properly built walls don't fail in normal timeframes, so this almost never comes up on our own projects. We do a lot of replacement work for failed walls built by other contractors.
Can a wall hold back groundwater?
A retaining wall isn't a waterproofing system. It's designed to hold back soil while letting water drain through it. A true groundwater issue needs additional drainage, dry wells, or a sump system — addressed alongside the wall, not by it.
What's the smallest job you'll take?
About $8,000. Below that, our minimum mobilization costs (delivery, setup, crew time) start to dominate the price-per-linear-foot. We'll tell you on the phone if your project is too small for us to do well — usually a referral to someone who specializes in smaller residential walls.
What's the biggest job you've done?
$84,000 — a 188 LF Nicolock Olde Greenwich wall on a Matinecock estate, working under Hoffman Landscapes. We've also done $100K+ in walls on a single property when phased over a few seasons.