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Erosion control & landscape walls — free on-site estimate from Mr. Hernandez.

  • Decorative garden walls to structural grade changes
  • Natural stone, brick, block & pavers
  • Licensed & insured · local Long Island crew

Need to hold a slope, fix washout, or define the yard? JNH Masonry builds retaining walls matched to your landscape. Long Island’s North & South Shore. Call/text (631) 965-1754 or request a free estimate.

Two ways to build it

  • Segmental block wallPrefab decorative block, dry-stacked
  • Block wall + veneerConcrete block core, faced with stone or brick

Need extra strength? In a block-core wall (B), steel rebar can be set into the cores, which are then filled solid with grout. See the strength guide to find what your wall needs.

Strength guide

How strong does your wall need to be?

Three levels, based on how tall the wall is and what sits above it. Each level adds to the one before.

Level 1

Low garden wall

Up to about 3 ft tall, level ground, nothing heavy on top.

Cutaway drawing: a low block wall on a compacted gravel pad, bottom course buried, with drainage stone behind it.up to~3 ftDrain stoneGravel padBuried course
What it needs
  • Firm soil under the wall, with topsoil and roots dug out
  • Compacted gravel leveling pad, about 6 in. thick
  • Bottom course buried below ground
  • About 12 in. of clean drainage stone behind the block
  • A drain pipe too if the site drains poorly
Level 2

Mid-height wall

About 3 to 4 ft tall, level ground, nothing heavy on top.

Cutaway drawing: a mid-height block wall on a gravel pad with drainage stone and a perforated drain pipe at the base.about3–4 ftDrain stoneDrain pipeGravel pad
What it needs
  • Everything in Level 1
  • Perforated drain pipe at the base of the drainage stone, vented to daylight
  • Geogrid may be needed even at this height, depending on the block, the soil, slopes and tiered walls
  • Check your town’s permit rules before building
Level 3

Tall or loaded wall

Holds back more than 4 ft of soil, or is over 2 ft tall with a driveway, parking, fence or other load above.

Cutaway drawing: a tall wall with a driveway above, geogrid layers tied back into the soil, drainage stone and a drain pipe, designed by an engineer.over4 ftGeogridDrain pipeDriveway loadP.E.
What it needs
  • An engineered design, which New York’s residential code requires for these walls
  • Plans usually prepared by a licensed professional engineer (P.E.), plus a permit check with your town
  • Reinforcement, such as geogrid layers tied back into compacted soil or a concrete footing with steel rebar in grouted block cores
  • Drain pipe and drainage stone (required behind reinforced walls)

How height is measured: the code counts the soil a wall holds back, which is the difference in ground level from the front of the wall to the back.

General guidance from the sources below, not a wall design. Your town’s rules and site conditions vary, and Mr. Hernandez will confirm on site.

Sources: Residential Code of New York State (2025), §R404.4 · Versa-Lok installation tips · Versa-Lok DIY installation guide · Versa-Lok geogrid · Allan Block basic installation · CMHA (formerly NCMA) TEK 15-07B, Concrete Masonry Cantilever Retaining Walls

Materials & methods guide

Retaining walls, explained

The main wall systems, how a wall is built from the footing up, and why drainage matters most.

Wall typesSegmental block, geogrid, stone, concrete, timber

Segmental block (SRW)

Interlocking concrete units, dry-stacked without mortar. Gravity walls rely on the block’s weight and setback (batter) to hold soil.

Geogrid-reinforced

For taller walls or extra loads (a driveway or slope above), layers of geogrid run back into compacted soil to tie the wall in.

Natural stone

Dry-laid stone is stacked without mortar, flexes and drains freely. Mortared stone needs a concrete footing and weep holes.

Concrete with veneer

A poured concrete or block core faced with stone or brick: structural strength with a finished look.

Timber

Landscape timbers cost less up front but are shorter-lived. Wood eventually rots and typically needs replacing.

Footing & baseHow a wall is built from the ground up

Excavation

Dig down to firm, undisturbed soil and remove topsoil and organic material from under the wall.

Compacted gravel base

Block walls typically sit on a leveling pad of compacted crushed stone, commonly about 6" deep or more and wider than the block.

Buried first course

The first course is set below grade. A common rule is at least 6", or about 1" per 8" of wall height.

Concrete footings

Mortared and rigid walls need a concrete footing below the frost line, typically about 3 ft deep on Long Island, per local code.

Video by Unilock, shown for general education.

DrainageThe #1 thing that keeps a wall standing

Drainage aggregate

Clean crushed stone behind the wall (commonly about 12") lets water drain instead of building pressure.

Perforated drain pipe

Runs along the base behind the wall and carries water out to daylight or a drain.

Filter fabric

Geotextile keeps soil from clogging the drainage stone.

Weep holes & grading

Mortared walls get weep holes. Grade and cap the top so surface water flows away from the wall.

Video by Western Interlock, shown for general education.

Height, permits & engineeringCheck with your town first

Taller walls

Walls over about 4 ft usually need an engineered design and a permit. Check your town or village.

Extra loads

Walls holding up a driveway, structure or steep slope may need engineering even when shorter.

Local rules

Long Island towns and villages set their own rules. Waterfront and wetland properties may need extra approvals.

Popular brands we can work with — ask Mr. Hernandez what’s best for your project.

Wall block
  • Unilock
  • Cambridge
  • Techo-Bloc
  • Belgard
  • Versa-Lok
  • Allan Block
  • Nicolock (Long Island based)

General guidance only. Typical figures vary by product, soil, and site — final specs follow the manufacturer’s instructions and your town’s code.

Not sure what’s right? Text a photo to (631) 965-1754Free Estimate
Before & After

Retaining Walls transformations

Before / After photos added as jobs finish.

Coming soon

Retaining Walls

Before / After photos added as jobs finish

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