Retaining Wall Construction Building A Timber Retaining Wall

1. Retaining Wall ConstructionBuilding A Timber Retaining Wall Developed by: Dr. Teri Hamlin Georgia Department of Education

2. Timber Retaining Wall • To level a steep slope • Enclose an area for a decorative garden • Elevate Beds

3. Which wood? • Treated pine and hardwoods are good choices for a timber retaining wall. • Avoid old railway timbers as these are treated with creosote, which harms some plants and heavy to work with. • Also need reinforcing rods secure the structure.

4. Steps: • Cut a beveled trench into the slope, wet the trench and tamp it well.

5. Steps • Set the first timber in place and level it. • This course will be completely buried in the ground.

6. Steps • The timbers are installed in a pattern similar to a brick wall with the butt ends of timbers in one course offset from those in the courses above and below.

7. Steps • Set a second timber on top of the first and bore a hole through the two timbers. • Use a heavy-duty drill with an extension bit. • A small bit burns out on long holes such as these. • Drive a reinforcing rod through the holes into the ground to hold the timbers firmly together.

8. Steps • In addition to the 15 degrees inward slope of the wall, vertical stability is achieved by installing tiebacks. • These are single timbers inserted perpendicularly from the face of the wall into the soil backfill to a distance equal to their height above the base of the wall.

10. Steps • Continue to lay the timbers • staggering the joints from one course to the next • Drill holes and use a reinforcing rod to pin each timber to the one below on each side of every joint. • Cut timbers with a sharp chain saw, and wear goggles to protect your eyes from flying chips.

11. Steps • Backfill where necessary. • For drainage, • Drill weep holes along the wall's length • Drill a row of holes above the ground

12. Steps • Fill the cavity. • You can top off the terraces with plantings or mulch.

13. Completed Jobs