Drainage Gravel..for drainage Concrete Blend..to make concrete Reinforcing Mesh..for inside your concrete

PRICE GUIDE

Drainage gravel is generally used to facilitate the movement of water around your property or more to the point away from it altogether! The most common usage is behind retaining walls where having a drainage system is extremely important but in other cases trenches can be dug under lawns or gardens and filled with drainage gravel to ensure these areas don’t become waterlogged.

Every landscape project is different and may require different amounts of drainage and to that end you can source a drainage gravel in a number of different sizes and in any quantity that you need.....be it a few shovels full, a trailer or ute load or a full truck load. The sizes available are: 5mm, 10mm, 20mm and 40mm and some helpful hints would be: As the size increases, the larger the air spaces so the greater the flow of water through the gravel. Unfortunately and importantly, as the size increases so it becomes harder to shovel! The most common sizes used are the 10mm and 20mm (a compromise between the above two points). Some sizes are now available, not only in a gravel form but also in a manufactured form ... from recycled concrete. Both are just as effective but the recycled products are generally a little cheaper and are lighter. If you need help in calculating the amount you need, just ring the office and we will confirm the quantity required.

So to confirm - How important is drainage?

The short and simple answer is …. EXTREMELY IMPORTANT! 

Whenever we build a wall, be it retaining a stable “cut” in the land or holding back fill, the effort we put into the drainage behind the wall is crucial to the success of the wall itself. By erecting a vertical or near vertical structure at a point where the land changes in height, there is the potential for it to become a “Dam Wall”. If this occurs, water will be trapped behind the wall where it builds up pressure and in some cases result in the wall failing and falling over.

In any DIY video produced, there will always be a strong emphasis on the drainage material used behind the wall being built. The whole reason for the drainage is so that during heavy rain or extended wet periods, that water does NOT collect behind the wall and has a way to “escape” This is done by placing an Ag Pipe at the base of the wall (behind it) and then covering this with Drainage Gravel. The quantity of gravel used will vary depending on the height of the wall and the amount of water runoff expected but as a general rule, the more gravel used the better.

One thing to avoid at all costs, is lining the back of the retaining wall with plastic as this will indeed result in water being held behind the wall. If you are concerned about dirt seeping through the joints in the wall, then you can line the wall with a filter cloth called Geofabric (Bidim) as this will let the clean water drain through and hold back the dirt.

When designing your wall, check the manufacturers’ brochures or the DIY videos on our website to get the full story on the importance of drainage and how to do it.

Concrete Blend (a blend of sand and gravel ready to add cement and water to make concrete) 

If concrete is needed for a project and using a truck full of premixed concrete is not an option, then it will have to be blended on site…so what does that entail? Well the good news is that at Centenary Landscaping Supplies, we have Concrete Blend already mixed in our Darra yard where the sand and gravel is blended in the correct ratios ready for you to use … so you don’t have to buy the gravel and the sand separately and mix them. Some important points to note: As with all materials, if you need a hand in working out the volume required, then give us a call at the office remembering that you can buy the Concrete Blend in any amount you like …from as small as a shovel full, to a trailer or ute load or even a full truck load There are two blends available, one with a 10mm stone and one with a 20mm stone and both are more than capable of performing most tasks around the home and garden be it a concrete slab for a garden shed, footings for a retaining wall, garden edging, etc. The larger stone will make a slightly stronger mix but is not as versatile as the 10mm and for that reason about 90% of all the blend we sell is mixed with the 10mm stone. If working out the volume of concrete blend required for a slab or path always allow for a little bit of shrinkage, as when water is added and all the voids are filled the total volume of the mix is slightly less.  For examples, if the exact mathematical volume needed is 2.3m, then closer to 2.5m would be needed.

Reinforcing Mesh 

If you are laying a concrete slab or a footing for a retaining wall then there will be a requirement to use some reinforcing. Most sheets of mesh are quite large which is why we have available smaller ones measuring in at 3m x 2.4m which are much more manageable for transporting and handling on site.