DIY Retaining wall tips
Tips and Tricks for Garden Walls and Retaining
- Start at the bottom or work your way up.
- You will need to make sure that all walls are properly locked and moved forward. Fill the space.
- Before gluing or applying caps, compact.
- Too much drainage is not possible!
- Never trim corners, use blocks only when necessary.
- In your trench, use short screed bars. This will make it quicker and easier to prepare the base course.
You should order all the items you require at once. Also, make sure you have enough money for any breakages or cutting.
Building a Fence on Top of a Segmental Block Retaining Wall
Contrary to popular belief building a fence behind or on top of a Block Retaining wall can be quite simple.
If there is only minimal retaining required (200-400mm), the fence can be built directly on the wall. The fence posts will pass through the walling blocks, and the concrete will be poured into the ground as usual. This can be used with any type of fencing: post and rails, colour bond post-and-rails, tubular panels, and pool fencing.
The fence must be placed behind the wall, not through it or on top of the wall, if the block Retaining Wall is more substantial than a metre in height. Segmental Retaining wall blocks don’t have enough space or void to allow for a fence post to be concreted directly inside. They also lack the strength and stability to support the weight of a fence.
Most walls are constructed using aggregate (Gravel), backfill, or in certain cases No Fines Concrete. This means that it is important to allow for the fence posts at the beginning of construction. For example, you could install PVC Piping to make the fence post fit in.
The Pros and Cons
Block retaining walls in wellington can be lightweight, cost-effective and simple to construct. Block retaining walls come in a greater variety of colours and styles than concrete sleepers. They can also be used to create curves or tiered walls with ease.
Block retaining walls are large in footprint, so blocks may not suit your needs if you have limited access or a small amount of space on your property.
For free advice and assistance in designing your Block Retaining Wall, call Australian Paving Centre.
Retaining walls and no fines concrete
What is No Fines Concrete?
It is concrete, without fine aggregates or any sand. It generally consists of an aggregate (gravel), cement, and water. It is coated with cement slurry to hold it together. The cement slurry dries quickly with the same strength as concrete, but without voids or air pockets. This makes NFC lightweight and allows water to flow through its honeycomb texture.
NFC can be mixed at-site in smaller areas, or bought from a reliable concrete supplier and shipped to larger commercial projects. Mixing NFC takes place at a ratio of 6 to 1 with 20mm maximum size clean aggregate and cement. The cement slurry should have a water content of around 40 litres per 100 kg. This is to ensure that the aggregate is evenly coated with cement slurry and does not run off.
NFC allows us to create Block Retaining Walls even in places and situations that would otherwise be impossible. These situations include:
- Excavation behind the wall may be restricted in areas that are near other structures or footings or borderlines.
- You can build a wall higher than the standard gravity wall construction methods.
NFC basically increases the depth of your wall. NFC can increase the depth of your solid brick masonry block by increasing its depth from 200 to 250mm (infill depth), or more depending upon how high your wall is.
It is recommended that each third and fourth block have a portion of the back edge removed. This will create a stronger structure by tying the NFC core-filled blocks and the NFC infill layer more tightly.
