When it comes to retaining walls, Brisbane has its share like many other cities. Anywhere there is a slope can certainly be in need of such a wall to prevent the garden from washing away in heavy rain. And heavy rain is one thing that Brisbane is likely to get a lot of, being in a sub tropical location. Even moderately heavy falls will saturate the ground and if it has been dug up for a garden it is quite likely to go sliding down the hill into your neighbour's block.
The thing is that you cannot just put an edging around a garden and call it a retaining wall. If the wall is going to keep lots of heavy soil in one place it needs to have strong foundations that are set into the ground deeply enough to keep it in place. Otherwise it will just get pushed down hill along with the soil it is supposed to retain.
Unless you have experience in this area, you will not be able to put up such a wall yourself. The gradient must be measured to see how deep the footings need to go. The steeper the slope, the deeper the foundations of the wall should be. This is a job for an experience professional. Often we don't realise just what weight wet soil has.
Generally speaking, soil that has never been disturbed and is covered in lawn will not move. However, it does move sometimes because in a new residential area has often been built up or levelled in places to facilitate building the homes. This means the soil may have been moved recently even if it is now covered in lawn and looks like it has been there for years undisturbed. If you then decide to dig part of it up to make a garden, all the rest is also compromised and can easily become a landslide if you get rain at the wrong time.
So if you have a home on a slope and want to create a beautiful garden, think about also making a retaining wall to keep it in place. Retaining walls are not ugly; they can really enhance the area and can be made from several different materials that are both attractive and strong. But don't just dig a shallow trench, fill it will brick or stone and call it a retaining walls. It will not do the work of such a wall, no matter how attractive it looks.
The thing is that you cannot just put an edging around a garden and call it a retaining wall. If the wall is going to keep lots of heavy soil in one place it needs to have strong foundations that are set into the ground deeply enough to keep it in place. Otherwise it will just get pushed down hill along with the soil it is supposed to retain.
Unless you have experience in this area, you will not be able to put up such a wall yourself. The gradient must be measured to see how deep the footings need to go. The steeper the slope, the deeper the foundations of the wall should be. This is a job for an experience professional. Often we don't realise just what weight wet soil has.
Generally speaking, soil that has never been disturbed and is covered in lawn will not move. However, it does move sometimes because in a new residential area has often been built up or levelled in places to facilitate building the homes. This means the soil may have been moved recently even if it is now covered in lawn and looks like it has been there for years undisturbed. If you then decide to dig part of it up to make a garden, all the rest is also compromised and can easily become a landslide if you get rain at the wrong time.
So if you have a home on a slope and want to create a beautiful garden, think about also making a retaining wall to keep it in place. Retaining walls are not ugly; they can really enhance the area and can be made from several different materials that are both attractive and strong. But don't just dig a shallow trench, fill it will brick or stone and call it a retaining walls. It will not do the work of such a wall, no matter how attractive it looks.
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