How deep should you bury a retaining wall?
Gravity and Segmental Retaining Walls. Embedment depth is typically 10% of the wall height, with a minimum of 6 in (152 mm). The footing, or first row of your retaining wall, should be about 4 to 6 inches deep and about 12 inches wide, or twice the width of the block you are using. The blocks should sit about halfway into the soil.The general rule of thumb is that a retaining wall shouldn’t be more than four feet in height, especially without proper stabilization and assessment of the ground.Retaining wall foundation depth should be 300mm if the soil is firm and well-drained, or 450mm if less firm and unstable. Dig out foundation [base on which wall stands] which must be twice the width of the wall. WONKEE DONKEE says to use a 215mm Hollow Concrete Block with a 450mm width foundation.The footing should be 16in wide (or more depending on you block depth) and 6-8in of compacted crushed gravel. The depth of the trench should also include the height of one full row of blocks which will be buried below the finished grade. So if your blocks are 6in tall, your footing trench should be 12-14″ deep.
Which soil is suitable for a retaining wall?
Usually, coarse-grained soils such as gravel, provide the best working conditions because they place less load on the walls, require less soil reinforcement, are easier to compact and are less affected by water. In this circumstance, gravel is the better option, this is because gravel does not retain water, whereas sand will collect the water and become almost mud-like after a certain amount of water.
Do I need a footing for a retaining wall?
In summary, retaining walls do need a footing to ensure they are structurally sound and have proper drainage to prevent cracking or collapse. Without a footing, the ground beneath the retaining wall can shift, which can cause the wall to shift as well, leading to cracking or collapse. If there is no drainage, water will compromise the safety and structure of your retaining wall. It’s vital that the wall is repaired or replaced if measures to ensure drainage weren’t taken. This can lead to an extensive amount of damage on the property, the expense of repairs and installation of a new wall.The Importance of Waterproofing Retaining Walls Preventing Water Damage: Without proper waterproofing, water can seep through retaining walls, causing erosion, and potentially damaging nearby structures, such as homes or buildings. Waterproofing prevents this water damage and protects your property.Poor drainage: Inadequate drainage is a leading cause of retaining wall failure. When water accumulates behind a wall, it increases the pressure on the structure, leading to instability and potential collapse.Without drainage, water builds up and damages the wall. Hydrostatic pressure from water causes cracks and collapses.Applying a liquid membrane over the retaining wall will grant an excellent level of waterproofing for your retaining wall. It creates a rubberised coating over the chosen area, which prevents water penetration. Using a good quality liquid membrane can ensure protection for up to ten years, and longer in some cases.
What is the best fill for a retaining wall?
Backfill the wall with gravel or sand. If you use sand, first cover the backside of the retaining wall with landscape fabric. This will keep the sand from seeping between the blocks. If you’re backfilling with gravel, you can pour the gravel after every course you lay. This is why the drainage system and gravel backfill are crucial; they prevent water from becoming trapped and help maintain the wall’s stability. Regardless of the style or material you choose, these components are the foundation of a long-lasting retaining wall system.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.While some retaining walls only require soil, a compacted, open gravel backfill is often the best choice for many projects. Here’s why gravel backfill stands out: ✔️ Provides added structure and stability. Improves drainage, reducing water buildup.Fractured rock is often the preferred choice for the drainage layer of retaining walls. Unlike rounded pebbles, fractured rock has angular edges, which help to create a more stable structure that locks together well.Any retaining wall four feet tall or higher should have a drainage system in place to give any water absorbed into the soil behind the structure somewhere to go, though shorter walls benefit from drainage too.
How to waterproof a retaining wall?
Cementitious coatings are cement-based products that provide a waterproof barrier when applied to the wall surface. They are particularly effective for concrete retaining walls. These coatings are easy to apply and bond well with the concrete surface, creating a durable waterproof layer. Polyurethanes Waterproofing: Polyurethane is a water proof chemical often used to waterproof materials like wood and ceramic. This water proofing chemical can also be used to make the water tanks waterproof and resistant to corrosion.Polyurethane is considered one of the best waterproofing materials. It can be applied seamlessly and penetrates the surface deeply and evenly. Thus, the polyurethane membrane will fill in even the finest cracks in concrete, reducing its water absorbency capacity.