How to Install a Timber Retaining Wall

A retaining wall is the ideal way to control erosion or level a sloping yard. Composite timbers made from recycled materials are a wonderful material choice because they don’t decompose.
DIY-2491263_0038963D4_retaining-wall_cw522

DIY-2491263_0038963D4_retaining-wall_cw522

Materials and Tools:

gravel
rebar
string
composite timbers
timber spikes
drainage pipe
drainage sleeve
stakes
shovel
hand tamper
level
tape measure
circular saw
sledgehammer
drill
spade bit

Steps:

1. Use landscape marking paint to outline the area where the retaining wall will be built. Drive stakes into the ground at each end. If the distance is greater than 8’, drive additional stakes so that the gaps do not exceed 8’. Tie a string to a stake at the wall’s desired height and stretch across to opposite stake or stakes. Use a string level to ensure that all the heights remain level and constant.

2. Excavate the entire wall base to a depth of 8". Spread approximately 4" of gravel evenly in the trench and rake the gravel smooth. Use a hand or power tamper to compact and level the area. Check for level and add or remove gravel as necessary until the appropriate height is reached.

DIY-1675646_GFI111_SEG02A

DIY-1675646_GFI111_SEG02A

3. Excavate the entire wall base to a depth of 8". Spread approximately 4" of gravel evenly in the trench and rake the gravel smooth. Use a hand or power tamper to compact and level the area. Check for level and add or remove gravel as necessary until the appropriate height is reached.

4. Install corrugated drainage pipe behind the first course of timbers and run the pipe to where the water can exit the area. Slip a drain sleeve over the drainage pipe to screen out sediment and prevent the pipe from clogging.

DIY-1675647_GFI111_SEG02B

DIY-1675647_GFI111_SEG02B

5. In similar fashion, cut timbers to appropriate length, lay in place, and level. Shims can be inserted where needed to make timbers level. To secure timbers, drill holes every two feet and drive 12' galvanized spikes into previous course. For top course, use spikes with a finished head for a more attractive look.

Tip: For added stability, it is wise to insert a few timbers perpendicular to the wall. Called "deadmen,” the timbers extend from the retaining wall deep into the ground behind the wall. Drive 2' lengths of rebar through the ends of the deadmen and into the ground.

6. Backfill the area behind the retaining wall with gravel to cover the drainage pipe. Continue backfilling with soil until the desired height is reached.

Keep Reading

Next Up

How to Repair a Walkway

Put an end to the cracking and crumbling with these step-by-step instructions.

How To: Installing a Fire Pit

A backyard gets more warm and hospitable with a stone firepit.

How to Design a Perfect Path

A good path not only tells you where to walk, it sets the mood for your landscape.

How to Build a Wood Pergola

Pergolas provide some much needed shade from the summer sun. Learn how to build a pergola with these step-by-step instructions.

How to Build a Stone Accent Wall

Learn how to build a simple dry-stacked stone wall and patio.

Build a Privacy Wall With Fence Panels

Instead of putting up an entire fence, build a barrier with wood panels.

How to Install Landscape Edging

Installing landscape edging can be easy if you follow the directions.

How to Pressure Wash Your Driveway

Erase years of wear and tear from your driveway in just a few simple steps with a pressure washer.

How to Create a Successful Hardscape

Landscape designers offer tips on creating and installing a successful hardscape design.

8 Things to Consider Before You Install a Pond

If you're picturing a sparkling pond filled with water plants, use our tips to figure out where to put it and what you'll need.

1,000+ Photos

Browse beautiful photos of our favorite outdoor spaces: decks, patios, porches and more.

On TV

Tiny House Hunters

6:30am | 5:30c

House Hunters

8:30am | 7:30c

House Hunters

9:30am | 8:30c

House Hunters

10am | 9c

House Hunters

10:30am | 9:30c

House Hunters

11am | 10c

House Hunters

11:30am | 10:30c

Fixer Upper

12pm | 11c

Fixer Upper

1pm | 12c

Fixer Upper

2pm | 1c

Fixer Upper

3pm | 2c

Fixer Upper

4pm | 3c

Fixer Upper

5pm | 4c

Fixer Upper

6pm | 5c

Fixer Upper

7pm | 6c
On Tonight
On Tonight

Fixer Upper

8pm | 7c

Good Bones

9pm | 8c

House Hunters

10:30pm | 9:30c

House Hunters

11pm | 10c

House Hunters

11:30pm | 10:30c

Good Bones

12am | 11c

House Hunters

1:30am | 12:30c

House Hunters

2:30am | 1:30c

Fixer Upper

3am | 2c

Follow Us Everywhere

Join the party! Don't miss HGTV in your favorite social media feeds.