Get matched with top retaining wall installation pros in Boulder Junction, WI

Generally speaking, a retaining wall should be between 3 and 4 feet high, depending on variables such as the wall-building material, the purpose of the retaining wall, and more. If you want your retaining wall to be taller than 4 feet, check with your local building ordinance office for the maximum allotment. You may also need a special permit for retaining walls over 4 feet tall.

Most railroad tie retaining walls have a life span of 20 to 30 years, though you may need to replace your wall sooner if it’s repeatedly exposed to heavy rain, runoff, and excess moisture. Railroad ties are typically treated with creosote, which makes them much more durable than untreated wood. Though they last longer, they don’t last forever. For the most longevity, make sure your retaining wall has a sturdy base and steel reinforcements. You should also install drainage to direct water away from the wall.

Railroad ties can be good for retaining walls, but it depends on the area. They have a desirable rustic look and are durable. The problem is they’re treated with creosote, a preservative the EPA says poses a risk to humans and wildlife. Over time, the preservative seeps out of the wood and into the ground. Many areas have banned the use of creosote-treated wood on residential properties. If your area does allow it, never use railroad ties near an edible garden or drinking water source. Instead, use wood that’s treated with an EPA-approved preservative or a wood-alternative composite material.

If you don’t backfill a retaining wall—either at all or adequately enough—the wall won’t drain well, and water will be able to pass through it. Poor drainage will lead to a warped wall or a buildup of hydrostatic pressure, which can eventually collapse your retaining wall. If you have particularly sloped land, consult a structural engineer to ensure your hardscaping is adding value to your home.