permeable surfaces

Project SOUND 2015 (c)

Out of the Wilds and Into Your Garden

Gardening with California Native Plants in Western L.A. County Project SOUND – 2015 (our 11th year)

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Let the Rain Sink In: Permeable Pavements, Patios, etc. to Make Your Garden More Sustainable

Kelley Dawdy & C.M. Vadheim

CSUDH/Madrona Marsh Preserve/Gardena Willows Wetland

Madrona Marsh Preserve June 6 & 11, 2015

Hard vs Softscape

Hardscape

• Inorganic things

• Walls

• Benches

• Sidewalks

• Patio

• Driveway

Softscape

• Organic stuff

• Plants

• Trees

• Groundcovers

• Vines

Project SOUND 2015 (c) 3

Hardscape


Hardscape Surfaces

Permeable aka porous or pervious

• Planting Beds (softscape)

• Mulched Beds (softscape)

• Gravel

• Permeable Pavers

• Stepping Stones

• Turf

Impermeable

• Asphalt

• Concrete

• Concreted brick or stone

• Concrete pavers


Hardscape Surfaces

Permeable aka porous or pervious

• Definition: surface that allows water to infiltrate underlying soil

• “Waters” your garden

• Filters pollutants

• Recharges water table

Impermeable

• Definition: surface that facilitates 100% runoff

• Cheaper

• Less maintenance (?)


Stream Health vs Impervious Surfaces


Rainwater Run-off

Groundwater (well water) Los Angeles River

Ballona Creek Gardena Willows


Stormdrain System


Santa Monica SMURRF The SMURRF cleans & diverts 500,000 gallons of “nuisance water” to local parks, cemeteries and CalTrans, DAILY!


The Life of City Water


Types of Permeable Surfaces

• Gravel



• River Rock or Mexican Beach Pebbles



• Rock Gardens



• Stepping Stones or flagstone



• Concrete steppers



• Loose lay brick



• Loose lay stone



• Mixed Materials


Design

• Eclectic is very hard to do well.

• What style is your house?

• Does your neighborhood have a style?

• What color is your house?

• What style are you drawn to: – English garden

– French country

– Formal

– Modern


Design = Less is More

How does this make you feel?


English Cottage Garden


French Country


Formal


Modern


Asian Gardens


Sub-base? • In my opinion, a sub-base is unnecessary,

unless you have expansive soil

– Palos Verdes & the “soils area” in Torrance

– Or you are installing a driveway

– Follow the directions for specific products

– Ask the seller of the product


Levelling/Subbase materials

• DG (decomposed granite). Levelling. Bulk only. Compacts better than sand.

• Sand, plaster. Levelling. Comes in bags or bulk.

• “Pre-mix” is a mixture of sand and gravel. Subbase. Bulk, only. Use as the subbase for expansive soil. Can be rolled or vibrated.

• ¾” crushed gravel. Subbase. Bags & bulk. Needed for driveways. Excellent drainage. Needs to be vibrated.


Rolling/compacting/vibrating/jumping

• Roller, sod. Rent $10/day

• Compacter/tamper. Rent, buy or make. Rent $7/day.

• Vibratory plate compactor. Rent. $72/day.

• Jumping Jack. Rent $90/day. Only use to compact very deep loose soil. Very dangerous.


Installation

• Weed mat? No, thanks.


Drainage

• Make sure that you have “positive drainage” away from your foundation.

• Code: 1” of fall (rise) over 4’ around the foundation. That’s 2% (1:48)≈(1:50)=(2:100).

48” Masonry level ≈ $50-75


Drainage

• Finished concrete 1 – 2% (1 – 2:48)

• Permeable surfaces 3 – 4% (3 – 4:48)

• ADA ramp 8% (1:12)

• Don’t forget the side to side drainage


Prepping the area

• At what height do you want the walkway or patio?

• An inch or 2 above the planter beds?

• A “step” down from the door? Use >1” or 4 - 7½” (code). 1-4” is a tripping hazard.

• Make sure that you are not covering a drip edge. As per code, grade must be at least 4” below.


Prepping the area for gravel

• Gravel and Mexican Beach pebbles are easy

– You’ll want 3-4” of depth

– Do you need to dig out (lower) the native soil?

– Does it need to be compacted? (Probably not.)

– Is there sufficient drainage/fall of the native soil?

– Buy gravel or beach pebbles.

– Dump them. Rake. Done!


Size of Beach Pebbles

Coverage (square feet/ 75 lbs. bag)

½” – 1” 12

1” – 2” 7

2” – 3” 4

3” – 5” 3

The problem

• After several years:

• Easy solution: buy more and “top dress”

• Hard solution: remove all the rock, clean & put them back.


Installing steppers

• Rectangular steppers


Installing steppers • Concrete or cut stone

– Remove enough soil to finish at the desired height

– Rake out 2” of DG (decomposed granite). Roll or vibrate.

– If using rectangular pieces, in a line, set-up masonry line (not string).


Installing steppers

• Rectangular steppers


Check square

Check the diagonals and/or check 3-4-5


Installing steppers, continued

– Calculate your spacing. Walk it to make sure it “feels right”. Approx. 30 – 36”

– Start laying out the steppers.

– Confirm that the edge is barely touching the line.

– Check side to side level (1 – 2% fall).

– Not “level”, tip it up, use a trough to add more DG.

– A tiny bit too high? Whack it with a rubber mallet or dead blow hammer.


Tools of the trade

• 48” Masonry level

• Masonry line

• Stakes

• Mallet (deadblow or rubber)

• Trowel, brick

• Sod roller

• Tamper


Excavating tools

• Mattock/pick

• Shovel

• Wheelbarrow

• Grading rake

• Push broom

• Hose with nozzle


Working with natural stone?

• Brick hammer/chisel

• 4½” angle grinder with a diamond blade

• 2x4” piece of lumber

• Sledgehammer – For very large pieces of rock that you want to break in

half, lay it over the 2x4”, approx. where you want it to break, lightly hammer it above the 2x4” until it breaks.


Back to the flagstone path

• Everything is the same, but

• Put the masonry string down the middle or off center, or

• Use a long, straight 2x4” to confirm that the tops of the flagstones are all in the same plain.

• Use your 4’ level to double check stone to stone “levelness.”


Common problems (downfalls)

• Use DG, not sand

• Check level

• No more than 2 (or 3) materials

• Use flagstone that is at least 2 square feet each

• “Work the puzzle”


Use flagstone of comparable sizes


They didn’t “work the puzzle”


Flagstone patios

Break-up the “grout” lines. Make “T”s.


Brick/paver walkways and patios

• Decide on a pattern

• Decide the type of brick


Curved bricks and steppers


Steppers

Bricks need borders

• Plastic Bend-a-Board

• Plastic or metal brick edging

• Mortared brick boarder


Brick/paver walkway and patio

• Prepare the native soil to the right height

• Confirm positive drainage

• Set the borders first

• 2” DG

• Roll the DG

• Start setting bricks/pavers

• Check “level” often

• If there are gaps, fill with DG, silica sand or polymeric sand (not permeable).


Types of pavers



Grasscrete-type products BodPave

TERRUM TruckPave Grasscrete Porous Pave


Final steps Tried and True Steps – done by every professional

• Bricks and brick-sized pavers can be vibrated.

• Water, water, water.

• Sit back and admire your work.

• Next day: check for “dancing flagstone.” Tilt up and add more DG.

• More water.

• Ice tea or beer.

• Sit back and admire your work some more.


South Bay Suppliers

• Thompson Building Materials. www.thompsonbldg.com 2400 Pacific Coast Hwy, Lomita, CA. (310) 326-5160

– Bulk: sand, DG, gravel, pre-mix, tools (all). Bagged concrete.

– Pavers, brick, grasscrete-type pavers, concrete steppers, used brick

• Thompson Building Materials – Rock Yard 1350 W Pacific Coast Hwy, Wilmington, CA. (310) 830-5584

– Bulk: Sand, DG. Bagged concrete. – LARGE flagstone, decretive gravel, & Mex beach pebble

selection


http://www.thompsonbldg.com/

South Bay Suppliers • Westwood Building Materials

www.westwoodbm.com 15708 Inglewood Ave, Lawndale, CA 90260 (310) 643-9158

– Bulk: sand, pre-mix, ¾” crushed gravel. Bagged concrete. Tools.

– Will deliver. ½ cubic yard minimum.

• Sepulveda Building Materials www.sepulveda.com 359 E Gardena Blvd, Gardena, CA 90248 (310) 436-1400

– Bulk: sand, gravel. Tools. Bagged concrete. – Nice selection of flagstone and boulders. – Will deliver.


http://www.westwoodbm.com/

http://www.sepulveda.com/

South Bay Suppliers • West Los Angeles Building Materials

www.flagstonespecialist.com 2431 S Sepulveda Blvd, Los Angeles, CA 90064 (310) 478-7276

– Bulk: sand, pre-mix, gravel. Tools. Bagged concrete. – Decretive gravel, flagstone, boulders, cobbles,

pebbles, used brick, used concrete

• Bourget Brothers www.bourgetbros.com Building materials: 1636 11th St., Santa Monica, CA (310) 450-6556.

– DG, decretive gravel, glass, tools Rock yard: 1810 Colorado Ave, Santa Monica, CA (310) 829-4010

– Beautiful flagstone. Huge supply. Expensive!


http://www.flagstonespecialist.com/

http://www.bourgetbros.com/

South Bay Suppliers • B.D. White

www.bdwhitetopsoil.net 19205 Prairie Ave, Torrance, CA 90503 (310) 370-5511

– Bulk: topsoil, sand, DG, pea gravel, ¾” natural gravel. – Landscape timbers & RR ties – Will deliver. Minimum = 1 cubic yard.

• Ewing Irrigation www.ewing1.com 20526 Gramercy Pl, Torrance, CA 90501 (310) 782-7821

– Bend-a-Board™, brick Snap Edge Pavers™ – Pavers


http://www.bdwhitetopsoil.net/

http://www.ewing1.com/

South Bay Suppliers • Anthony’s Ready Mix & Building Supplies

www.anthonysreadymix.com 4500 Manhattan Beach Bl., Lawndale, CA 90260 (310) 542-8585

– Brick, flagstone, bagged concrete – Concrete and mortar colors – Concrete stains

• Home Depot

– Bagged gravel and sand. – Tools. – Pavers & brick – Concrete pavers. – Pre-mixed concrete – 60 & 94 lbs bags.


http://www.anthonysreadymix.com/

• My favorite mason: Joaquin Barraza 213/453-7642 “Saturday work” Or his employer: Land Matters 310/372-7604

• My favorite place to see permeable pavement: Mother Nature’s Backyard in Gardena Willows Wetland Preserve


permeable surfaces

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