Want to build a retaining wall on your own but are concerned with those hard to reach areas?
We’ve got you covered!
We’d like to introduce an easy-to-use material that you can absolutely do on your own. With No-Fines concrete, you can install a retaining wall that will have the look of a professionally handled construction.
What Is No-Fines Concrete (NFC)?
Basically, it is just what its name suggests, concrete without any fine aggregates or sand. It consists generally of aggregate (gravel), cement, and water. The aggregate is coated with the cement slurry binding it together, it dries with the strength of concrete but with voids or air pockets. This makes the NFC lightweight and allows water to easily pass through its honeycomb texture making it perfect for other projects that require permeability like driveways.
No-Fines Concrete can either be mixed on-site for smaller areas or purchased from a reputable concrete supplier and trucked in for larger commercial applications. It is mixed at a 6:1 ratio volume of 20mm maximum size clean aggregate and cement. Water content should be such that the cement slurry evenly coats the aggregate and retains a wet or glossy appearance without excess slurry running off, this is typically around 40 litres per 100kg of cement.
Most masonry blocks would have an average depth of 200-250mm but by using No-Fines Concrete, you can increase that depth from 200mm up to 500mm or more depending on the height of your wall.
Benefits Of NFC
- No-Fines Concrete allows the building of block Retaining Walls in areas and conditions where normal construction methods may not work.
- It may be applied to areas where excavation behind a wall is limited; either due to being on a boundary or close to other structures or footings.
- No-Fines Concrete can be used to construct a wall to a greater height than standard gravity wall construction methods.
- The depth of a retaining wall may also be increased with the use of No-Fines Concrete.
Applications Of NFC
No-Fines Concrete can also be applied to different projects aside from retaining walls.
Walls In Buildings
NFC can be applied to hard-to-reach areas within walls. This can apply to buildings as well.
Laying your pavers can be tricky especially when your surface requires a drainage system. You’ll need to secure the pavers beside the drainage. To ensure they fit properly and securely, we recommend using NFC.
No-Fines Concrete can also be used for levelling courses during construction. You can even use No-Fines Concrete if you need a concrete finish for your driveway or the pathway going to your garage.
Car Park Paving
Paving the area for your driveway or car park should be done with precision. The key here is to ensure that the pavers do not move or shift over the course of time from the friction brought about by your vehicle’s tires. No-Fines Concrete is a great material to use when sealing your pavers. It makes them last longer and also easier to clean.
With its insulating characteristics because of its large voids, No-Fines Concrete can be applied to tennis courts and other outdoor surfaces.
For an in-depth guide on how to install the NFC, please check this PDF link. Once you have installed the first course of blocks and have them levelled, follow these simple steps below.
- Fill all voids of the block with No-Fines Concrete. To ensure that all voids are filled completely, we recommend on rodding the NFC into the core.
- Backfill up to the specified depth with the NFC. There are different ways to get the No-Fines Concrete mix into the back of the wall. Each site may use a different option as each site will be different.
- Continue to pour the No-Fines Concrete until the two-course lift is complete. You don’t need to let the NFC cure between pours since it will start to cure soon after they have been placed.
- Additional courses of blocks can be stacked after you’ve completed the lower two-course lift.
- Let the No-Fines Concrete cure for at least 2-3 hours once you’ve reached a height of 4ft on your wall.
It is always recommended that every third or fourth block should have part of the back edge removed. This would give a far better adhesion tying the NFC infill layer and the NFC core-filled blocks creating a far stronger structure. If any No-Fines Concrete spills over on your wall block, we advise you to remove it before it cures. Using a brush and clean water will help you remove the cement quickly.
Use a low permeable file to finish off the wall. Ensure that a filter fabric has been placed on a horizontal layer above the No-Fines Concrete before placing the low permeable fill on top. If you are unsure of how you can finish the top of your wall, you can always ask for help. Contact your nearest Australian Paving Centre for your friendly free advice on how to use NFC.