Browse Forums General Discussion 1 Aug 15, 2011 3:59 pm Hi, we have plans for our renovation that include an extensive core filled bessa block retaining wall, as we have to cut into our block a fair bit. We're on a slope, so the wall is pretty small at the front of the house, but by the time it reaches the back will be up to about 1.5 metres - not including footings. I'm getting quotes for the footings and blockwork as per the plans, but have come across a number of places that build walls from natural stone - sandstone being the most popular from the looks of things. I would imagine natural stone would be more attractive than bessa blocks, but firstly, would it still comply with engineering? If it says bessa blocks on my plans - can I use something else?? Would a sawn block wall be about the same size in depth as a bessa block one? What about strength, and durability? Do they need to be waterproofed? I'm sure I could call my engineer before I go ahead with anything, but would like to be a bit better informed beforehand - and as you can tell, I have no idea about walls. Thanks for any help Re: core filled bessa blocks vs natural stone retaining wall 2Aug 15, 2011 4:24 pm I am currently looking to build a sandstone wall for our house which we get the keys for on Thursday. The info I have relates to the Brisbane City Council so you know. When I spoke to council not long ago I was told that any retaining wall over 1mtr high will require engineering etc, but a natural stone wall, being uneven rock is fairly negotiable as to where the 1mtr would be measured. For 1.5, I would be using stones up to about 800mm, backfilling and using the batter of the ground and a garden to bring the ground level up, or use another row of smaller rock to make it up. For an idea of cost, I have been quoted $1100 for 24t of rough sandstone (not cut with a rocksaw) delivered to my block. I have access to a free bobcat & excavator as well so I can't give any idea fo their costs. For me, I like the look of natural rock. There is something dated about besser blocks that have been rendered or whatever finish chosen and a 1mtr lump of sandstone will hold more than a mtre of besser block could ever hope to. I built about 50mtrs of rock wall at our old house, sat the rocks on the ground and backfilled. Nothing ever moved, even nearly 10 years on now when we drive past, everything is sitting the same as the day we made it. Re: core filled bessa blocks vs natural stone retaining wall 3Aug 15, 2011 4:26 pm Also, make sure you check the price you are being charged if you go with a rock wall. Two quotes I got today, for the same weight of the same material delivered, varied $400. Re: core filled bessa blocks vs natural stone retaining wall 4Aug 15, 2011 4:29 pm I agree with phippsy. Basically, if you want to go with sandstone rocks, stagger the retaining wall. to do that, you would build a wall of say 1000mm on the boundary, back fill it till its level with the wall, then move some distance back and erect another wall of 500-600mm. This creates a multi-tiered effect that really improves the aspect and gives you opportunities to create multilevel gardens. IMHO, engineered walls would look very industrial unless you were to fix natural stone tiles onto the face - an additional cost. Suburbia is where the developer bulldozes out the trees, then names the streets after them. Re: core filled bessa blocks vs natural stone retaining wall 5Aug 15, 2011 4:52 pm Thanks for the replies - we don't have a huge block, so I think I'd probably be looking at the sawn blocks and building them straight up - rather than staggering boulders - although I do agree they look nice. Are these kind of walls as strong? They would need concreting in between the layers I imagine, and would have to be put in place with machinery too I guess. I've got engineering already done - but would it need redoing? And then passing through council again? Or just an amendment? Re: core filled bessa blocks vs natural stone retaining wall 6Aug 15, 2011 7:45 pm Engineering etc would depend on what council area you are in. Sawn blocks will still be very strong structurally and shouldn't need cement between the layers and will stack very neatly but if space is a premium then the block wall may be better. Any small excavator worth their salt should be able to throw a rock wall together in no time flat. This pic is the wall I built at our last house probably 2 years after it was finished. The rocks at the front are roughly 300-400mm and the larger ones up beside the red commodore are closer to 750-800mm, They were dug in roughly 50-100mm, no more and back filled Like ⋅ Add a comment ⋅ Pin to Ideaboard ⋅ Re: core filled bessa blocks vs natural stone retaining wall 7Aug 15, 2011 7:47 pm I should add though, the original ground level in that yard, was all the same as the driveway on the right and sloped up to the driveway on the left, roughly 1mtr overall. There was a garden bed/hedge along the walls that took up the difference in height from the top of the rocks to the grassed area. Versaloc is a mortarless besser block system that still needs a properly engineered footing. If you just do a 400x200 footing it will fail in time. At 17m long you need it… 1 15514 Hi, planning on using the attached stone pieces in my bathroom. I want to remove stains and gloss seal. Can I get some advice on best way to remove stains and best… 0 6700 2 5482 |