Mix your own cement, part one.

WELCOME TO OUR BLOG YOU ARE INVITED , TO BROWSE AS LONG AS YOU LIKE. Anyhow, here I will publish my own diary and what I see happening in the world, and when I do not have much to say, I will write posts from my life story. 

Anyhow, you can also find this article at, http://oldman-lifeworks.blogspot.com,  

My other sites; https://sites.google.com/site/menfrancoreconciliation/  

Farming today compared to the old way, My life my struggles, 

Hub Pages, DIY brickwork. and this article at this link, Mix your own cement. 

Dear readers, this divise you see above is a concrete mixer, it is used to mix concrete and mortar on site, it is very helpful to have one, if you want to mix concrete and mortar. So, let us see how it is used on building sites to mix concrete and mortar. 

Mix your own cement

Mix your own cement.

Welcome to our article, Mix your own cement. 

Dear readers, this is going to be a long article, because we want to explain how to mix concrete, in several ways, we are also going to mix other things as well, and the name mix your own cement covers them all. In this blog, we have split the original article in half and we are making two blogs, 

We are writing this article how to mix your own cement, because we want to pass our knowledge of how these things are done. So, we are writing  this article for those people that are willing to do building work themselves, but they need a bit more knowledge to give them the courage to do it; and above all for those people that live in poor countries, where building skills and material are scarce, therefore, they need some knowledge to try building themselves, as long as they can buy Portland cement and/or lime to mix it with; so, this article can be D.I.Y article. 

This article is going to be a long and detailed way of how to make concrete from scratch, using Portland cement and other basic materials, we will also describe how to mix mortar for the bricklayer and cement plaster, just by using the most basic building materials, by mixing them with Portland cement and/or lime. We will describe how these things were/are done, because we believe that it is helpful to know that.

We must say that today building anything has become easier, because most things that we need are ready made for us to use, provided we are living in a city or large town in the western world and in many other parts of the world. In our case we are talking about how to use cement and the things that we can do with it. So, let us suppose that today we need concrete; we can order it, and have it delivered whenever we want it.

But these things were not so in the past, in the past people that were building had to have their own skills how to mix their own concrete, how to mix their own mortar and other things, and sometimes they had even to find the building materials themselves, before they could start to build anything, they were not easy times and people in the know, kept their knowledge for themselves. But today it is different, the knowledge they had and kept to themselves has become insignificant compared to the things that we know and do; so, to keep any knowledge for yourself is the wrong thing to do, because it is not going to help you, but it can help other people if it becomes common knowledge. 

Therefore, this article is being written, in the hope that our articles can help those poor people that are not aware that they can build a better place, if they learn to recognize the basic materials, they need to use for building a place for themselves. Most of the building materials that we are talking about are available anywhere in the world, because they occur in the natural state as they are part of this great planet earth, so, what are those building materials you may ask?  And how we mix them you may want to know, so, here is a link from YouTube that shows you how to mix concrete.

How to Mix Concrete by Hand - YouTube

We would like also to point out with these photos here under what is available in Brisbane Australia, and then we will talk about those building materials that occur anywhere in the world.

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What are these building materials? 

Anyhow, I know how to mix concrete, since I have mixed it by hand and with a mixer hundreds of times, so, let us see these building materials and how to use them. 

First, let us see what these materials are. Today you can buy these building materials ready to mix, and all you need to do is to add the right amount of water and mix them, but here we want to start everything from scratch:

In building anything with cement, there are five main sort of materials that we need to recognize, before we start mixing our batches of whatever we want to mix, they are; bricklayers’ loam, plaster sand, river sand, gravel, and Portland cement; with these materials you can build anything, some of these materials sometimes are called with different names, but let us describe what these material are like.

Bricklayers’ loams is a very fine sand, some of these fine sands could be a tiny bit sticky and when it is wet enough you can almost make a small ball in your hand, but it will always collapse as there is not enough sticky material in it, but if you add the right quantity of cement and water (and something else if required) it is easy to lay bricks.

Plaster sand is very fine sand but not as much as bricklayer’s loams it does not stick together by itself, therefore, it will stick together only when you add cement and water to it, this type of sand is used to plaster the walls and can be used to lay concrete blocks it is ideal to use this sand provided it is very fine, in this part of the world we call this Besser sand.

River sand, or washed river sand is a type of sand coarser and thicker than plaster sand, as the name suggests it comes from the river, in this parts of the world because Brisbane river is salty water it is washed and sieved, but it is possible to find deposit of this sand in some rivers that can be used straight away,  sometimes this sand can be used by itself to lay a top layer on a fresh laid concrete, but its use is mainly used to mix it with gravels to make concrete.

Gravel or gravels are small stones again these small stones can be found in or near the rivers; in most places if there is proper supplier, gravels are graded so one can order them as they are required, and this is what we need to make good concrete. But if you happen to be in the middle of nowhere, they don’t need to be graded properly to use for concrete and one could use a mix of different size provided you know what you are doing. But one must be careful that this ungraded building material is free from silt and organic stuff.

Today of course building people rely more from the specialized suppliers, and they order through these suppliers what they need. You can even buy bags of ready mixed materials that you can use just by adding water. These materials are good to use, if you have a small job to do, but they become expensive to use if you have a large job. 

What we have described above are the main materials required to build most cement things, of course, you must know how to use them, and that is what we are going to write next.

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Since there is not enough room to describe the cement properties, let us describe it here; cement is like the glue that when mixed with sand, gravels and other aggregates makes these materials stick together. The word “cement” can be traced back to the Romans, who called this “opus caementicum” to describe masonry that resembles concrete. We dare say that the Romans used burned limestone which when you add water turns into hydrated lime and also they used something called pumice that was collected from some part on Vesuvius it was a sort of cement that when you added water would become harder than if you just used lime, this is more or less how I have been told. As you can see there are two main bonding materials that can be used to make concrete and mortar.

Anyhow, the cheapest way is to mix your own cement, or when the job is big then the best way is to order premixed concrete. If you need mortar or plaster, you must mix your own from scratch or pay the price of the bagged premixed materials.   

Mixing your own concrete from scratch. 

Because I am an old tradesman, I have been asked a few times the following from some friends. 

We want to mix some concrete ourselves; can you please explain us how to do that? We don’t have a mixer and we want to learn how to do that using the tools that we have; we have a couple of shovels and buckets a wooden float and some other small tools. We are a couple of strong blokes and we do not mind doing hard-physical work, it will be a pleasure to do some useful exercise, so, tell us how to mix concrete?

Okay, since you do not mind working hard, I will be glad to tell you how to mix your concrete by hand. Now, let us assume that you have the material on site, and that you are ready to mix your concrete. To mix concrete by hand, you need a flat platform where you can mix your concrete, this platform does not need to be made on purpose, all it is needed is a hard surface, perhaps a slab of existing concrete can be helpful or anything at all, as long as this surface is not loose, because you don’t want to mix the soil with your concrete.

To make is easy, we must assume that the bloke that sold you the building material, has sold and delivered some concrete blend. Now what is concrete blend, you are wondering; so, let us explain, concrete blend is gravel and river sand mixed together approximately two part of gravel and one part river sand, so, you don’t have to mix them anymore, it is ready to use.

To make normal concrete you need to mix by volume six containers of concrete blend to one container of Portland cement, depending on the quality of the concrete blend this may vary, so what we do next; we know that we need a lot of concrete, so, you measure say twelve bucket of concrete blend and put that on our platform, then you measure two buckets of cement to mix with the blend. These are the quantities to keep in mind, (6 to 1) this is a small batch of concrete, and you can make it bigger or smaller, if you keep that 6 to1 ratio. Sometimes this ratio may vary. 

Now before you mix your cement with your blend; make sure that everything is ready, because once you start this process you must continue until you finish. Since everything is ready you can spread the cement on the concrete blend, after doing that you take your shovels fill them up and start turning your mixture around, by pushing the shovel under and turning it over, you need to turn your mixture a couple of time; say first from A to B and then from B to A, so, everything is in the same place, after doing that and you are satisfied that your mixture is mixed even, you can make a well in the middle of it, and add a bucket of water, if the water is absorbed quickly, then you know that you must add more water, if a fair bit of water remains in the centre then you can start folding the outside mixture in the middle, you can add some water as required, but don’t get carried away with adding too much water, because you need to add water bit by bit, you see this is one of those things that you learn as you do it and not before.

You have done all that and now you have a heap of this mixture half mixed; here again you take your shovel and turn your mixture from A to B while sprinkling some water on it, you may need to do this a few times sprinkling water and turning your concrete mixture from B to A and from A to B, you need to do this until you have an even mixture that it is well mixed. Now you have your concrete ready to place wherever you need to place it. 

This is how mixing concrete was done in the old days, it was a hard work and it was not as accurate as it is today with the ready mixed concrete truck that can deliver concrete to your job whenever you need it, and all you have to do is to lay your concrete slab, or whatever you need to do. Anyhow, the description above, can be used if you are in the middle of nowhere, and you need concrete.  

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Learn the art of mixing cement. 

Learn to recognize and use the building materials when we mix cement. 

Now, that we have written what are the building materials, and we have explained how to mix concrete by hand, this procedure can be applied to mix mortar and plaster etc. We have also explained how you can recognize the raw building materials.

You see, let us imagine that you need concrete, you live in the middle of nowhere and you have only a few tools, but you now a faraway place where you can go and buy Portland cement; you are not going to buy anything else at that place, because it is too far, it will be costly to bring it in, so, the rest of the concrete materials you are going to find near the river banks. I know it is like going back in time a hundred years ago, but there are parts of the world that are still that far back. Therefore, learning how to recognize the basic building materials for making concrete, and then mixing concrete by hand can still be useful today. So, we are writing these articles, hoping we can help any do it yourself small owner builders.

Now, we have to add that what we are writing here is how we have done these things, and we know they work, however, it is only our view, and they work well in all minor jobs, but if you have large important jobs, you must consult the local experts.

Now let us see how we mix concrete with a mixer. 

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Mixing concrete with a mixer. 

Okay, let us make this clear, there may be several ways how to mix you concrete; you can mix it on the ground, as we have described above, you can mix concrete in a wheelbarrow, if you have a wheelbarrow with a good tray, or you can mix it with a mixer which is helpful to have. But what are the different procedures when you mix, in order to achieve the best result with the least amount of time and work:

The greatest difference for mixing concrete and other cement materials is mainly this: when you mix by hand you can achieve the best result by mixing the materials with the cement before you add water, as this helps to make a more even mixture quicker: But when you use the mixer you don’t need to do that, in fact, you can have better and quicker result, by following this procedure hereunder:

Start the mixer and put in the mixer some water, approximately the proper amount to mix the whole batch, you know how much water to use once you have made a few batches.

Now before we proceed to mix, let us talk about the water amount. On building sites, it is near impossible to tell you how much water you need exactly, since the materials you are using contains an unknown quantity of water, therefore, the quantity of water varies, you see, the wetter the materials are, the less water you need and vice versa if they are dry.  

Now, let us assume that because you are new at doing this job, you are using a dry small bucket to measure the quantities of the building materials; in this case you have gravel and river sand in separate heaps, you know that this concrete is going to be mixed 6 to 1, but overall, this batch you are going to mix 8 small buckets of gravel four of river sand and two of Portland cement:

Now the quantities above are how the best and strongest cement can be achieved, with a minimum of Portland cement used; very likely these quantities are written in the specifications, if you have any specification written, and the ready mix people use those amounts and have a perfect concrete, because the concrete mixer will mix it well and as dry as possible. But by experience on building sites, we use a bit more river sand and a bit less gravel, as this makes it easier to work with overall.

Now let us go back to mix our concrete:  

So, after you have poured the water into the mixer, you put one single bucket of gravel and while the mixer turns put the two small bucket of cement into the mixer, the cement in the mixer will immediately mix in the water and the first bucket of gravel will make sure that it does not stick to the mixer, because it will cut though any lumps easily, now you add four buckets of river sand, and this again will mix very quickly and become like a thick cream, all you have to do next is to add the other seven bucket of gravel, once you have done that you only need to wait a little bit for the mixer to mix it properly and your concrete is ready. Now all you must do is to tip your concrete in a wheelbarrow and take it to the place you need to concrete.

This is the quickest and best way to mix concrete in a mixer, as I have done it for thousands of times, but I need to say that on building sites, where there is plenty of cement to mix and the workers have to try not to injury themselves, by lifting hundreds of bucket full of material all day long, they use to measure the materials by the shovelful, but you have to be an expert at doing that to get everything measured right. I hope this description of how to mix concrete is clear enough.

Before we leave these concrete discussions, we want to add more information; you see, concrete in itself is very strong in compression, but is lacks strength under tension, so, to make concrete very strong and last a very long time you need to use steel in the concrete; here is a link that will help to understand some of these issues.

 How to Make Concrete Even Stronger: 6 Steps (with Pictures)

 

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Now as we have said at the beginning, because the original article was too long, we have split this article in half. So, in our next blog, we will continue to talk about, how to mix mortar, plaster, or cement topping and other things, see you soon. 

To see more click on this link, Mix your own cement. 

Mixing mortar, plaster, or cement topping.  

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The hybrid rock wall, part theree.

WELCOME TO OUR BLOG YOU ARE INVITED , TO BROWSE AS LONG AS YOU LIKE. Anyhow, here I will publish my own diary and what I see happening in the world, and when I do not have much to say, I will write posts from my life story. 

Anyhow, you can also find this article at, http://oldman-lifeworks.blogspot.com,  

My other sites; https://sites.google.com/site/menfrancoreconciliation/  

Farming today compared to the old way, My life my struggles, 

Hub Pages, DIY brickwork. and this article at this link, DIY Retaining walls. 

Here we are trying to show you, how an hybrid rockwall can look like. Anyhow, this picture has been taken from the internet, where I could not find what I wanted, but this is how a hybrid rock wall can look like. But in the text is a differen shape.  

Welcome to our blog, DIY Retaining walls, part rhree. 

Completing the hybrid rock wall, and other things. 

So, before we build this retaining wall, we must work out how much lean against the bank we want, here we must keep in mind, how tall and how thick is the wall, we don’t want the wall to lean too much and rely only on the dirt behind it to hold it back, but at the same time we want to lean it against the bank so that the weight of the wall is used to hold the dirt back.

Here we must go back to look at what happens if you lean a monolithic object to the point it is going to fall; what happens here is that the monolithic object is going to fall, only after its centre of gravity falls outside the area of the base. Now we don’t want to go this far, and we don’t want to use the centre of gravity to decide that, but we are going to lean the wall about two third of the thickness, so that the very top layer is still vertically one third of its thickness above the base; we believe that it is very safe to go this far and the wall would stand up even if we don’t backfill it. Anyhow, in our case we are not going to backfill it, because we have cut the bank exactly as the wall is going to be, you see we are going to use the bank as a template, so, we believe that we are not going to backfill it at all.

Now that we know how much we are going to lean the wall; we are setting a leaning profile on every corner leaning approximately 10 to 12 centimetres per metre and we are ready to resume building our hybrid rock wall. But there is still another important thing to work out; we need to make sure that when it rains the water that seeps behind the wall can run out, so, we must leave a way to drain this water out and at ground level is the right place to do that, so, we choose a few spots about a meter apart and mark them, then when you lay next course of stones make sure that you leave a space between the stones that the water can run out, you must also leave the back free of abstractions for a course or two around this space, so, in this space after laying the front stone, just lay some smaller stones dry against the bank to stop the concrete blocking the drain, then you can resume to concrete the lot. Alternatively, you can lay a few short pieces of pipe across the wall for drainage, but you have still to make sure that they are clear of any obstruction at the back near the bank.  

So, now you can go back to mix some cement to lay your stones, you can mix a batch of river sand four to one that you can lay between the rocks to give them a bit of grip, you are laying the rocks in a straight line that you have tied on the profiles, when you do that make sure that this cement does not come too far forward, because you still want the rock wall to look like a rock wall, at the same time do not forget that you have to leave these spaces with no cement at all for the seepage where you have marked, after you have used the batch of river sand and cement and laid say a course of rocks, you can mix one or two batch of concrete to fill the back of the stones, then you repeat this procedure until you build the entire wall.

At the top of the wall, because the wall in not going to be level, you may have to do some adjustment to follow the height of the ground, here you have to use common sense the best way you can, if you happen to have enough wide and long rocks that can be used for a coping, use them to finish your wall, if not, just use your common sense and use anything that is available, even if it is going to be a strip of concrete in the back of the wall, so that all the wall is tied up.

I hope I have explained well enough for you to follow my way of building this hybrid rock wall. Here I want to add that this is just one way out of several other ways that can be used. A lot depends how the bank has been cut and if it follows very closely the shape of the wall, so, you can use it as if it is formwork, but if there is going to be some back filling to be done, you may have to consider some temporary formwork that can be easily removed before you backfill. All these things can vary from job to job, and if you see that it is hard to build your hybrid rock wall, then you must consider other ways to build your retaining wall.    

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Why we need these retaining walls? 

Let us explain again why we build these retaining walls. You see, when the block of land is steep, it requires a lot of work to be done, if you want a small portion of your land flat, so that you can stand and enjoy whatever is there to enjoy and do whatever you want to do in the open air.  See the photo here under, they have built a Besser block retaining wall with an indent in it, mainly to give extra strength to the block wall and to put this concrete slab and use this indent with whatever they want to do next. Note that above this block wall there is another sleeper retaining wall, these sorts of things are very costly, and we must plan it out before we start, anyhow, under below we are going to write about a Besser block retaining wall, first just a normal strong retaining wall and after that we are going to build a leaning Besser block wall, similar to the hybrid rock wall. 

There are many types of retaining walls, above is a Besser-block retaining wall, they are usually made with hollow concrete blocks, 190 x 190x 390 mm, laid with mortar 10 mm thick joint, steel reinforcement bars are placed in the hollow part of the bolock, then they are filled with concrete, once the wall is dry enough to with stand the strain. 

Building a Besser block retaining wall. 

Besser blocks retaining walls require a reinforced concrete foundation with steel starter bars placed exactly in the centre of the hollow part of the block, when you look at the wall from the front or back, and if possible, a bit close to the side where the pressure of the soil is going to be, but that can be asking too much from the concrete man and the steel fixers. So, a profile must be in place before you can even concrete the foundations, or fix the steel in the foundation, because all measurements need be known and easily measured while working on it.

This is a very demanding job and it is not a do it yourself job. So, the name that I have given this article DIY retaining wall would not apply in this case, you see I apologise because I was forced to use DIY just to overcome the problem of the title that happens when we start a new article and find that the name we have chosen has already been taken.

Anyhow, when you start laying the first Besser block in most cases, it is helpful if you can start the first course with an open block, this block looks like a square C, and you lay it with the open side facing away from the bank that it is going to hold back when everything is done, the corners are built with normal blocks and most of the walls are built with blocks that look like an H, so, it is easier to fill up with concrete, once the wall has been built. Now while the block layer is laying the blocks, he will have to lay horizontal steel bars between the courses of blocks as specified, if there is a plan and specifications, or use common sense, or copy from the specifications of a similar job he has done, the vertical steel bar will be inserted from the top before or while pouring concrete into the blocks.

Now the reason why we need to use an open C shaped block for the first course, it is because it is necessary that before we fill up the blocks we remove the mortar that has fallen down at the bottom of the blocks while we were laying them, you see, we want a solid base and we want the concrete to bind around the starter steel bars that we have laid in the foundation and this is the best way to make the retaining wall as strong as we can. Once that is done, we can fix a plank against the openings, and we are ready to pour the concrete in the wall. 

Here we must say that for this retaining wall we have not mentioned any drainage yet, so, what happen to the water that seeps behind the wall needs to be worked out, you see, sometimes when we build walls this strong, there could be a reason that we do not want any water past the wall, it can be part of a base of a house being built, so, we have not even left any weep holes in the wall, because there is going to be a drainage pipe laid behind the wall surrounded by gravel. The wall might also be treated with special paints to waterproof it.

This is one type of blocks retaining wall, and I am going to write about another type, where we lean the retaining walls towards the bank for future back fill that it is going to hold up, this is a large job that we did years ago in a yard of a new large home in Redhill a Brisbane suburb. We are going to write it here, to show you another type of retaining wall and the many ways that can be built.

 

Redhill backyard problem solved. 

Years ago, we worked on this part brick house in Redhill, we say part brick house because the top floor of the house and the interior was made of timber, so, it was a brick veneer, the base was solid bricks and blocks, it was a large house, on a large block of land had two street frontages. It was on a hill and the difference between the front and the back yard was a lot, but the two street frontages was good, because the house was being built on the higher part of the block of land, where it was nearly flat there and almost level with the road, so, there were no problem building the house; but the back yard was very steep, in some places could have been up to 45 degrees.

So, when we finished the brickwork on the house we were asked from the owner, if we could build some retaining walls, because the backyard was useless as it was. So, after discussing the financial part how he would pay us; we discussed how we could fix the back-yard building block retaining walls. So, it was agreed that we had to lay these block retaining walls leaning a few degrees towards the bank. We had to build concrete stairs on one side, so that the house could also be entered from the back street, so, working together with the owner we did the following.

Because you cannot build a very high wall on the road boundary, first a section of about 4 feet wide (1.2 m) was dug and a foundation was poured, with starter steel bars as needed and the main wall was set about a meter from the road where the first retaining wall was to be build, this was the main foundation for a start, some of the small foundations and other adjustment we had to work out as the work progressed.

The decision was that we had to build the wall leaning towards the bank for extra strength; you see, when building retaining walls the weight of the retaining wall with the weight of the foundation must be more than the weight that the backfill can move, if possible that you can build a very strong monolithic wall and foundation together this is the best solution, in this case it was not possible, because the job was too big, beside that you need to have a very wide and heavy foundation and a very strong bond between the foundation and the wall, since this bond between the foundation and the wall is the weakest point unless it is concrete and poured together, but we were using blocks to build the wall, therefore, it had this weakness at the bottom of the wall, therefore, by leaning the wall towards the bank, the weight of the wall becomes  the first point or resistance.

Now, how much we must lean the wall was left to us block layers, because for sure there will be problems, and there were several problems to overcome; the first problem is that if you have to return the corners it cannot be done, but we had corners on the boundaries of the joining block of land, so, we had to think how to overcome this drawback, for this it was decided that we would not build the corners as usual, we should treat them as separate, but we would place a corner steel rod every course, instead of every second course, as in the wall itself.

There was also the possibly that while we were building the wall, if we lean it too much it could fall on the inside, while we were building it, so, we had to strike a balance. Knowing that this first wall was going to be no more than 3 meters high, we worked out that if we lean the wall 5 centimetre per meter, the top of the wall was going to be about 15 centimetre back from the perpendicular, the blocks were 19 centimetre wide and it would be okay, as once the wall was built it could stay up on its own without falling inside, but while we were building we should be very careful not to apply any extra weight on the leaning wall, just for fear that this could happen we added a couple of block piers behind the wall, this would not only make the wall safe for us while we were building it, but it also would make the whole wall stronger. 

Anyhow, we built this block wall placed the reinforcing rods in place, we also built some concrete steps on one side of it, so, that if you happened to be on the back road you could walk to the house, the ready-mix truck came, and the wall was filled with concrete and that was the first stage finished. We had to wait for this wall to become strong before we could backfill it, and then we could build another retaining wall halfway the backyard to finish the job.

Dear readers, be warned that this type of work can only done from very experienced block layers, as it breaks all the rules in the building trade, but we did it and it worked. 

Anyhow, this article is becoming too long, so, see you in our next article, Mix your own cement. 

To see more or the entire article click on this link, DIY Retaining walls. 

DIY retaining walls, part two.

WELCOME TO OUR BLOG YOU ARE INVITED , TO BROWSE AS LONG AS YOU LIKE. Anyhow, here I will publish my own diary and what I see happening in the world, and when I do not have much to say, I will write posts from my life story. 

Anyhow, you can also find this article at, http://oldman-lifeworks.blogspot.com,  

My other sites; https://sites.google.com/site/menfrancoreconciliation/  

Farming today compared to the old way, My life my struggles, 

Hub Pages, DIY brickwork. and this article at this link, DIY Retaining walls. 

Today is easy to build retaining walls, there are firms that specialize and make it easy for the average bloke to build them like in this photo above. You see, some of these concrete blocks are made to be laid dry, so, the average bloke can lay them, and if it not right the first time you can relay them, since there is no mortar between the joints that sticks them together. 

Welcome to our blog, DIY Retaining walls. part two.

Link Block Mortar-less Walls

Link Block Mortar-less Retaining Wall Blocks

This is a different type of retaining walls made with dry blocks, the mortar is not required, it is a low wall easy to build, so, most people can do it themselves. Now let me tell you this, on the internet I have found this local supplier who has placed a few short videos how to build these walls; the videos are at the bottom of the page, please use the link here-under, I reckon it is worth to watch them, if you want to build any retaining walls. As I have said this is only a local supplier in Brisbane Australia, therefore, the same materials may not be available where you are living, but by watching these videos you are going to learn something useful, if the link works.   

No need for Mortar

http://centenarylandscaping.com.au/product-guides/retaining-walls/firstqualityretainingwallblocks/?gclid=CPOE9-

So, I hope you have used the link above and you have been able to see the videos. Anyhow, whatever you have learned can be helpful one day.

Now, let me describe how to build a garden rock retaining wall.

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I believe that rock retaining walls blend well in the garden, as they are natural, since rocks are found everywhere in the natural state agong trees and grass. So most times is the way to go. 

 Building a garden rock retaining wall

To build a garden rock wall as shown in the picture is a lot harder than you think, and you need to know how to go about it, you see, you need to have a good eye to see how the rocks that you have can fit together to make a wall. There are a few ways how to do this depending how tall the wall is going to be and lots of other things.

You see, if you have only a very low wall you can just lay one single rock one after another, or two rocks one on top of another making sure that you choose the best face to show at the top and at the front, the other part of the rock can be hidden in the ground, or at the back since you are backfilling behind the wall; in this case it is not necessary to use any concrete, as the stones can be laid dry, but if you want you can use concrete.

Before you start the wall, you must dig all the grass and loose soil, even if your wall is going to be low. If the wall is going to be in a place where the ground is slopping down, make sure that you dig at least a few inches into the solid natural ground, so that the wall you are building can sit on firm natural ground, so, your wall is not going to slope down the first heavy rain you have after building.

Now, in this example, we are building a low stone wall and we are not going to use anything to bind the wall together, so, there is no cement or anything else between the stones, in this case because there is nothing to stop the rainwater to run between the stones you don’t need to worry about drainage. You see, one of the greatest problems with retaining walls is the water that can build behind them, the water and wet soil puts pressure on the wall and if the water cannot get out the wall is going to fail.

Now it is helpful to have a look at some stone retaining wall, and for this reason in mind I have found this link in the Internet; so, have a look at the pictures in this link; www.australianrockwalls.com.au/  there are several types of stone walls, now you can start thinking how and why they have been built that way.

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Deciding to build your own rock wall. 

Here let us assume that you need more space, because you want to build a car port, and put a trampoline for the kids. So, you have been digging in the backyard, and finally you are satisfied that they can fit them in the space you have made. But now you have this bank that stands almost vertical in the backyard, it looks ugly, and you know that when the first heavy rain comes it is going to start washing it down, and worse still it may collapse. So, you think of building a retaining wall to hold the soil up. 

For this reason, you have had a couple of quotes and had a good talk to the contractors as you did not want to spend more money that was strictly necessary, they did their best but still you cannot afford to pay the full price, beside that you found that if you lay a dry stone wall, ether you have to use stones that have been cut at the quarry and they cost a lot, or you have to have a rock wall with a wider base and this is going to take away some of the space you created when you dug, so really you need to think about it.

So, you have decided to build the stone retaining wall yourself, what you have decided is that you are going to build an hybrid stone wall, which you believe can do the job without costing too much; therefore, you have looked for a rock supplier and ask for prices of the different materials you may need, because you think that you can afford it, if you do the job yourself.

By pure chance you have learned from the blokes that have given you the prices, how many cubic meters of rocks you need and other things that you were not sure before; well done sometimes in the building game things work out this way, you learn a bit from here a bit from there and then you can decide what to do with the information you have collected. There is nothing wrong for doing this, unless you do it purposely to learn something, but if it does not work out, then it is okay to use what you have learned from them.

I have to say that it has been done to me many times and that I have done this myself; not only on quoting but also in buying something new, if I have to buy something that I have never used before, I go to at least three places and inquiry about it, by asking the right questions not only I learn how much it is going to cost me, but I have learned how to use whatever I was going to buy in the first place, of course, I end up buying from one of them what I wanted to buy in the first place; sometimes I call this let me go first to spy and then to buy, I know that some of these people are going to feel a bit hurt, for using their time for nothing, but so what, sometimes you win and sometimes you lose, as I have said it has been done to me as well and I have felt a bit hurt, when I had to spend some time working out a price to build something, and at the end I did not get the job, so, I spent all that time for nothing, but that is life and we should accept the outcome whichever way it goes. Anyhow, now let us go back to building the rock wall.

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Start building the hybrid rock wall. 

This hybrid wall that we are going to build is a big job, it starts at the same level, as we have dug the ground approximately level, but because we are building the wall only to the height of the natural ground level, it is going to start from almost nothing and at the highest point will be 1.8 meter, it is really two walls that meet and forms a square at the highest point.

Here we must say that today some people think that this should not be done, as this is neither a rock wall nor a concrete masonry wall, as it mixes about everything, but so what, if it is convenient, why not do it? I must say that in my life time I have built walls like this with whatever was available on the site; and I mean everything in fact I was using stones that were laying in this small creek bed, and pieces of concrete that we had broken to do some alterations and old bricks, some concrete and some mortar, this has happened a few year ago and last time I have seen the owner he said that the wall is still there. So, most things can be done if you know that it has got a good chance to last a long time.

Let us go back to build our hybrid rock wall. Now, to build this wall you need a few cubic meter of rocks, because you want the wall to look as a rock wall, you don’t need very big rocks or special size rocks, because you can use the cement wherever necessary to fill the gaps and this is good, since the cement is less costly, you need a mixer, you need some gravel, sand and cement; and of course, you must have the tools to do the job.

You got all this on site, and you can start to build. First of all, drive a couple of pegs in the ground, exactly where you want the face of the wall to be, tie and stretch a line on these pegs and see any adjustment that you need to do before you start laying the first stone. What you are looking for here is that the bank you are going to build the wall against has been dug straight, it is almost vertical or a few degrees sloping, you have dug a shallow foundation, because you want the wall to be strong and last for a long time, so, you are satisfied that the foundation is going to be solid enough, since it is well below the original natural ground, therefore, it can hold a lot of weight and pressure, because the ground is very compact. 

You have done all this, you have set the pegs again so that your wall is set to be at least 10” thick overall, you have chosen this thickness because most of the large rocks seem to be that thick, so now you are ready to lay the first course of stones, mix a few batches of concrete and lay it in the foundation and then before this concrete sets lay the first course of stones on this concrete making sure that the bottom of the stones are below ground level, so that the entire stone wall seems to start from below the ground; once you have done that you can fill the back of the stone with concrete a bit above ground level but below the full height of the stones, because you want to leave enough room to lay next course of stone easily. Now the wall is all set to go, but we need to reset how we must continue and complete the hybrid rock wall, the right way with the right lean against the bank. You need to lean the wall against the bank, so that the weight of your wall by itself adds strength to the wall. 

This blog is becoming too long, so, we will complete to build the hybrid rock wall, in part three. See you soon. 

To see more, or the entire article click on this link, DIY Retaining walls. 

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