Table of Contents
What kind of wood should I use for a retaining wall?
The best kind of lumber for these walls is Douglas fir pressure treated with preservatives to discourage rot. It will be green or brown in color and rated for earth-to-wood contact. For timber walls, large timbers for can be very expensive, which is why railroad ties are a common alternative.
How do you anchor a wood retaining wall?
How to Anchor Retaining Walls Install the foundation and first three courses of the timber wall with timbers, landscaping screws and a drill. Build a deadman anchor to install every 4 feet down the length of the wall. Unroll a strip of landscape fabric and cut it with scissors to fit against the back of the wall.
Is a wood retaining wall cheaper?
The cheapest types of retaining walls are wood and concrete blocks, followed by concrete and stones or bricks. Each material has benefits and drawbacks, including strength, longevity, and attractiveness.
Does a 2 foot retaining wall need drainage?
These walls need a drainage system regardless of the wall height. If there are poor draining soils such as clay behind the wall, there needs to be drainage incorporated the wall system. Clay when wet is very weak, so it is essential to provide a way for water to escape from behind the wall.
How tall can a wood retaining wall be?
Your walls can be as long as you want, but limit the height to 4 ft. Add more terraces as needed to retain higher slopes, stepping them back about 4 ft.
How much does it cost to build a wood retaining wall?
For wood retaining walls, you can expect to pay between $16 and $28 per square foot for a professionally installed wall. Taking on the job by yourself can bring the cost down to as low as $10 per square foot. On the whole, wood retaining walls cost about $19 per square foot.
How long will a wooden retaining wall last?
A timber retaining wall can last a little over a decade, if treated properly. If not maintained, the lifespan of a timber wall is around 3 to 5 years. To keep its fresh look, timber requires serious maintenance. The material will hold up for so many years only if its pressure-treated with chemicals.
Are wood retaining walls good?
Wood retaining walls provide structure, stability, and natural beauty to gardens and landscaping projects. They continue to be a popular choice because of the natural look they provide and because of their low price point, relative to expensive masonry and concrete retaining walls.
How do you waterproof a wood retaining wall?
One way to protect wood is to use a wood preservative, which forms a tough barrier to for moisture and rot to break down over an extended period. You can apply wood preservative using a paint brush, use a solid insect repellant like creosote or weather sealer.
How deep should posts be for a retaining wall?
Retaining wall posts should be at least as deep as the amount of soil they will be holding. A good rule of thumb is to halve the height of the wall and then add 4 inches. This is how deep you should place your posts.
What is the least expensive retaining wall to build?
What is the cheapest retaining wall material? Treated pine and is the least expensive material. Hardwood is more expensive than treated pine. Railway sleepers are another – slightly more expensive – option and are built to withstand ground and water contact. Concrete sleepers are more expensive.
What is the cheapest method of building a retaining wall?
The cheapest type of retaining wall is poured concrete. Prices start at $4.30 per square foot for poured concrete, $5.65 for interlocking concrete block, $6.15 for pressure-treated pine, and about $11 for stone. Installation or supplies, such as drainage stone or filter fabric, are not included.
How many deadmans are needed for a retaining wall?
Install one dead man every 6 to 8 feet around the entire wall. Continue building up the retaining wall, using landscaping screws to secure each timber. Cover the ground in front of the retaining wall with 2 to 4 inches of bark mulch.
How long should a Deadman be on a retaining wall?
Deadmen should be at least 1 1/2 times as long as the wall is high at the level where they’re inserted. This allows them to penetrate beyond the soil that’s actually bearing on the wall.
How thick should a retaining wall be?
Retaining walls can be tricky to build as they need to be strong enough to resist horizontal soil pressure where there are differing ground levels. One of the things you must get right is the thickness of the wall. It should be at least 215mm thick and bonded or made of two separate brick skins tied together.
Do you need gravel behind retaining wall?
Second, a retaining wall must have properly compacted backfill. In order to provide proper drainage, at least 12 inches of granular backfill (gravel or a similar aggregate) should be installed directly behind the wall. Compacted native soil can be used to backfill the rest of the space behind the wall.
Is a wood retaining wall cheaper than concrete?
Concrete retaining walls are generally more expensive than timber retaining walls which is something that you will need to keep in mind when you are setting your budget but a well built concrete retaining wall will last for 60 years or more, so it should never need replacing.
WHY DO retaining walls fail?
A retaining wall will fail when it is unable to withstand the force on it created by the soil behind it. Water is heavy, and as it builds up in the soil behind the wall the force acting on the wall dramatically increases. At some point, that force may exceed the capacity of the wall and cause the wall to fail.
What is the strongest type of retaining wall?
Concrete and Masonry Retaining Walls Poured concrete is the strongest and most durable choice for retaining walls. It may also be carved and formed to look like mortared stone depending on your taste.
