Here's an excerpt from Polished Concrete Secrets, that we hope you find interesting and informative:
Introduction
We commenced building our home in January 2008, and completed most of the finish off work of our home in October of the same year. This story of constructing the floor for our new home commences with our research and design in later half of 2007, and concluded in early February 2008 – just before the frame for our new home was erected. The finished flooring system was impressive and had our concreter and the concrete grinders taking photos for their portfolios. It’s incredibly hard wearing, easy to keep clean, looks beautiful and was cost effective to create.
I think this is an important story to tell because all too often, builders (whether registered or owner builders) only think of traditional subfloor and floor covering options. I wanted to highlight that there are other options too, where the floor and all of components that make it up are considered as a whole system – a system that provides an easy surface to live on and clean, gentle penetrating heat during winter, and thermal mass that keeps the inside temperature to a very comfortable temperature during summer (and providing more natural cooling at no cost and far better than an air-conditioner could provide). The flooring system we used draws from a combination of what we are starting to see more commonly in new commercial premises, using construction techniques used in northern Australia, and considering heating systems commonly seen in Europe. I also think that a floor should provide a wonderfully large canvas to add some individual creative flair.
Planning
In the initial stages of planning our new home, we researched a range of flooring systems. Concrete slabs and what I would call stump and bearer floors seemed to be the most common and straight forward. We found that in most cases, the subfloor was laid (whether concrete or stump and bearer), and a new home would be constructed to lockup on top of this. Floor coverings would be laid in the later stages of finish off.
Leanne and I talked at length about what we wanted out of our new floor. It had to be hardwearing and durable floor as our new home was to be on a farm. A floor that looked clean and was easy to clean was also very important. We didn’t want to connect to the power grid, and opted for sustainable power options, so providing means of efficient heating and cooling that required little power to run was also really important. Using concrete as a flooring material was starting to look like a more viable option in that we could utilise the thermal mass of the floor to make heating and cooling more efficient. The inherent and stable temperature of the ground would also help towards our heating and cooling needs. A suspended stump and bearer floor would need to be insulated, would provide less thermal mass and could not make benefit of the inherent ground temperature.
Spend the time to get the location of your new home right. Consider aesthetics and cost.
The aspect and look of our new home also had a bearing on the type of floor we would choose. Sitting essentially in the middle of a 70 acre grass paddock, our home needed to sit close to the land and sprawl across it. The roof of our home was reasonably high given it was only of a single storey, and a sprawling veranda would skirt all four sides. With 40 squares of roof area in total, we felt our home would look more attractive sitting on the ground. I wanted traditional looking red pavers to dress the floor of the veranda too, and I hoped these would be cheaper buy and lay than extending a stump and bearer floor to the outer edges of the veranda. Everything seemed to be pointing to us to a concrete slab floor.
Then one day, Leanne mentioned that she had seen a creative surface that could be applied to concrete floors. It was an epoxy resin compound that contained coloured chips. The effect it produced was much like terrazzo flooring. This sparked our interest and started a journey of researching similar concrete floor finishing systems. Isn’t it amazing what comes into your attention and experience once you are on a course of thinking? We began to notice the flooring used in our workplaces, and in new shops we walked through. Concrete polishing was just starting out and we really liked its natural appearance. We did also notice some examples of concrete polishing that we didn’t want. In these examples we found heavy scratching made in the final sealer that looked like general wear and tear. We also found some grinds not being done completely up to the wall edge. Internal corners were also left unground. This, we believed was due to the grind being done after the frame was erected. Concrete polishing seemed like the effect we wanted but we definitely needed to do more research.
Roughing out
We found roughing out the site of our new home a little tricky, and I know this sounds strange, but I’d never had to measure out something so big before that needed to stay as a rectangular shape. We chose the aspect we wanted to see out of the windows we would look most out of and drove a peg into the first corner. What I didn’t bank upon was that although the ground looked reasonably flat to the eye at a distance, it really was quite uneven. The next problem to overcome was a barbed wire fence that extended right across the middle of where our home was going to be – cutting right though it lengthways. So Leanne and I hopped over the fence a few times to readjust the pegs when we came to measuring diagonal corners and making the site relatively square.
The orientation of our home, and the floor system we had chosen were to be significant factors in determining the energy rating of our home. I’ve provided more details on this later in this book.
Our soil
Variable moisture content in your subsoil may mean that a sturdier slab is required.
Our next job was to organise for a soil foundation assessment to determine the stability of the layers of subsoil that would be under our slab. Essentially, this assessment would determine if a standard M class slab would be sufficient, or whether a sturdier H class slab was required (that of course would cost more too). At this stage we had what looked like a level(ish) spot of grassy paddock for our home and were reasonably clear where the outer corners of our home would be. With no driveway in yet, the soil tester rolled up at my in-laws place in the adjacent paddock and was escorted by my father in-law in his old red Massey Ferguson tractor down to our home site.
We told the soil tester that we had chosen a nice level site, and he didn’t really believe us. He pulled a theodolite out of his ute, checked a few levels and announced that we would need to cut into the paddock to create a level site and the deepest point of this will be at least 500 mm. My first thought was maybe I should have used a level to rough out the best site? My second thought was that such a significant cut would equate to a lot of soil to needing to be removed, considering our home with veranda was around 400 square metres and we wanted a flat area of at least 10 metres bordering each side.
The soil tester bored two test holes just in from opposing corners of where the slab was to go. The first was taken to 500 mm and found only red loam soil with some moisture found at the base of the hole. The second borehole was dug to two metres, where the first 700 mm was dry and of red loam soil, the next 300 mm was again red loam soil but had some moisture and then after that was red brown soil with some clay and was relatively moist (ie could be kneaded between the fingers). This meant that as we would need to cut across this to level our home site, we would be pouring our slab not only over changing soil types but also over changing moisture content. This last aspect of changing moisture content alone meant that the risk of failure in an M class slab would be high and that an H class slab was recommended.
Reflecting on the process of soil testing, and talking to tradespeople after, I think that some soil testers are quite pragmatic, while others are risk averse. Our soil tester was definitely from the latter ilk, but I think we have a more stable slab because of this. I believe what we have now is less prone to cracking than what we may have seen from an M class slab.
Preparation
After designing our slab, we next needed to select contractors for the work and make sure any material not supplied by these contractors was purchased and ready for use.
Selecting a concreter
If you are an owner builder, get the concreter to ‘own’ your slab. Get them to mark out, add the colour and to float in the seeds you want.
Selecting a good concreter was difficult for us, although persistence did pay off. I remember working through the telephone directory firstly ringing and then sending them a copy of the floor plan if they were able and had the inclination to quote. We are about 30 minutes away from a few regional centres, all with substantial residential developments underway. I think many of the concreters were over-quoting simply because our slab was different and out of town and that they were likely to make better money pouring similar slabs in town. But it was difficult to see this when we were receiving quote after quote that were at almost 50 percent higher than our original estimate[1]. We persisted and ultimately found a concreter through a mutual friend that quoted a reasonable price and was interested in taking on the challenge of pouring our slab.
You can also save $1000’s in concrete colour by only using coloured concrete in the top surface of the slab.
We talked through what we wanted on a few occasions and our concreter came up with a few ideas of his own that helped produce a better result at less cost. One of these ideas was to only use coloured concrete in the top layer of the slab. Clever coordination would be needed on the day of the pour, but with around 40 cubic metres of concrete needed for our slab and one bag needed per cubic metre, this was likely to save us at least $1000 in concrete colour. This may not seem a lot, but we were looking for every opportunity to save money.
Given that we were owner builders, we wanted to make sure that one person was completely responsible for each important stage of the build. This meant that if anything was not done in accordance with the plans then we would have only one person responsible for correcting an issue that may arise. Applying this strategy to the pouring of our slab, we asked the concreter to quote on all tasks related to the slab including marking out, adding colour, and seeding. I figured making someone completely responsible for the slab was far better than having to rely on owner builder insurance if things went wrong.
[1] See Attachment A in Concrete Flooring Secrets for more details on our original estimates.
Buy your copy now for only $19.50 by clicking the Buy Now button below, and going through to our secure download site:
Introduction
We commenced building our home in January 2008, and completed most of the finish off work of our home in October of the same year. This story of constructing the floor for our new home commences with our research and design in later half of 2007, and concluded in early February 2008 – just before the frame for our new home was erected. The finished flooring system was impressive and had our concreter and the concrete grinders taking photos for their portfolios. It’s incredibly hard wearing, easy to keep clean, looks beautiful and was cost effective to create.
I think this is an important story to tell because all too often, builders (whether registered or owner builders) only think of traditional subfloor and floor covering options. I wanted to highlight that there are other options too, where the floor and all of components that make it up are considered as a whole system – a system that provides an easy surface to live on and clean, gentle penetrating heat during winter, and thermal mass that keeps the inside temperature to a very comfortable temperature during summer (and providing more natural cooling at no cost and far better than an air-conditioner could provide). The flooring system we used draws from a combination of what we are starting to see more commonly in new commercial premises, using construction techniques used in northern Australia, and considering heating systems commonly seen in Europe. I also think that a floor should provide a wonderfully large canvas to add some individual creative flair.
Planning
In the initial stages of planning our new home, we researched a range of flooring systems. Concrete slabs and what I would call stump and bearer floors seemed to be the most common and straight forward. We found that in most cases, the subfloor was laid (whether concrete or stump and bearer), and a new home would be constructed to lockup on top of this. Floor coverings would be laid in the later stages of finish off.
Leanne and I talked at length about what we wanted out of our new floor. It had to be hardwearing and durable floor as our new home was to be on a farm. A floor that looked clean and was easy to clean was also very important. We didn’t want to connect to the power grid, and opted for sustainable power options, so providing means of efficient heating and cooling that required little power to run was also really important. Using concrete as a flooring material was starting to look like a more viable option in that we could utilise the thermal mass of the floor to make heating and cooling more efficient. The inherent and stable temperature of the ground would also help towards our heating and cooling needs. A suspended stump and bearer floor would need to be insulated, would provide less thermal mass and could not make benefit of the inherent ground temperature.
Spend the time to get the location of your new home right. Consider aesthetics and cost.
The aspect and look of our new home also had a bearing on the type of floor we would choose. Sitting essentially in the middle of a 70 acre grass paddock, our home needed to sit close to the land and sprawl across it. The roof of our home was reasonably high given it was only of a single storey, and a sprawling veranda would skirt all four sides. With 40 squares of roof area in total, we felt our home would look more attractive sitting on the ground. I wanted traditional looking red pavers to dress the floor of the veranda too, and I hoped these would be cheaper buy and lay than extending a stump and bearer floor to the outer edges of the veranda. Everything seemed to be pointing to us to a concrete slab floor.
Then one day, Leanne mentioned that she had seen a creative surface that could be applied to concrete floors. It was an epoxy resin compound that contained coloured chips. The effect it produced was much like terrazzo flooring. This sparked our interest and started a journey of researching similar concrete floor finishing systems. Isn’t it amazing what comes into your attention and experience once you are on a course of thinking? We began to notice the flooring used in our workplaces, and in new shops we walked through. Concrete polishing was just starting out and we really liked its natural appearance. We did also notice some examples of concrete polishing that we didn’t want. In these examples we found heavy scratching made in the final sealer that looked like general wear and tear. We also found some grinds not being done completely up to the wall edge. Internal corners were also left unground. This, we believed was due to the grind being done after the frame was erected. Concrete polishing seemed like the effect we wanted but we definitely needed to do more research.
Roughing out
We found roughing out the site of our new home a little tricky, and I know this sounds strange, but I’d never had to measure out something so big before that needed to stay as a rectangular shape. We chose the aspect we wanted to see out of the windows we would look most out of and drove a peg into the first corner. What I didn’t bank upon was that although the ground looked reasonably flat to the eye at a distance, it really was quite uneven. The next problem to overcome was a barbed wire fence that extended right across the middle of where our home was going to be – cutting right though it lengthways. So Leanne and I hopped over the fence a few times to readjust the pegs when we came to measuring diagonal corners and making the site relatively square.
The orientation of our home, and the floor system we had chosen were to be significant factors in determining the energy rating of our home. I’ve provided more details on this later in this book.
Our soil
Variable moisture content in your subsoil may mean that a sturdier slab is required.
Our next job was to organise for a soil foundation assessment to determine the stability of the layers of subsoil that would be under our slab. Essentially, this assessment would determine if a standard M class slab would be sufficient, or whether a sturdier H class slab was required (that of course would cost more too). At this stage we had what looked like a level(ish) spot of grassy paddock for our home and were reasonably clear where the outer corners of our home would be. With no driveway in yet, the soil tester rolled up at my in-laws place in the adjacent paddock and was escorted by my father in-law in his old red Massey Ferguson tractor down to our home site.
We told the soil tester that we had chosen a nice level site, and he didn’t really believe us. He pulled a theodolite out of his ute, checked a few levels and announced that we would need to cut into the paddock to create a level site and the deepest point of this will be at least 500 mm. My first thought was maybe I should have used a level to rough out the best site? My second thought was that such a significant cut would equate to a lot of soil to needing to be removed, considering our home with veranda was around 400 square metres and we wanted a flat area of at least 10 metres bordering each side.
The soil tester bored two test holes just in from opposing corners of where the slab was to go. The first was taken to 500 mm and found only red loam soil with some moisture found at the base of the hole. The second borehole was dug to two metres, where the first 700 mm was dry and of red loam soil, the next 300 mm was again red loam soil but had some moisture and then after that was red brown soil with some clay and was relatively moist (ie could be kneaded between the fingers). This meant that as we would need to cut across this to level our home site, we would be pouring our slab not only over changing soil types but also over changing moisture content. This last aspect of changing moisture content alone meant that the risk of failure in an M class slab would be high and that an H class slab was recommended.
Reflecting on the process of soil testing, and talking to tradespeople after, I think that some soil testers are quite pragmatic, while others are risk averse. Our soil tester was definitely from the latter ilk, but I think we have a more stable slab because of this. I believe what we have now is less prone to cracking than what we may have seen from an M class slab.
Preparation
After designing our slab, we next needed to select contractors for the work and make sure any material not supplied by these contractors was purchased and ready for use.
Selecting a concreter
If you are an owner builder, get the concreter to ‘own’ your slab. Get them to mark out, add the colour and to float in the seeds you want.
Selecting a good concreter was difficult for us, although persistence did pay off. I remember working through the telephone directory firstly ringing and then sending them a copy of the floor plan if they were able and had the inclination to quote. We are about 30 minutes away from a few regional centres, all with substantial residential developments underway. I think many of the concreters were over-quoting simply because our slab was different and out of town and that they were likely to make better money pouring similar slabs in town. But it was difficult to see this when we were receiving quote after quote that were at almost 50 percent higher than our original estimate[1]. We persisted and ultimately found a concreter through a mutual friend that quoted a reasonable price and was interested in taking on the challenge of pouring our slab.
You can also save $1000’s in concrete colour by only using coloured concrete in the top surface of the slab.
We talked through what we wanted on a few occasions and our concreter came up with a few ideas of his own that helped produce a better result at less cost. One of these ideas was to only use coloured concrete in the top layer of the slab. Clever coordination would be needed on the day of the pour, but with around 40 cubic metres of concrete needed for our slab and one bag needed per cubic metre, this was likely to save us at least $1000 in concrete colour. This may not seem a lot, but we were looking for every opportunity to save money.
Given that we were owner builders, we wanted to make sure that one person was completely responsible for each important stage of the build. This meant that if anything was not done in accordance with the plans then we would have only one person responsible for correcting an issue that may arise. Applying this strategy to the pouring of our slab, we asked the concreter to quote on all tasks related to the slab including marking out, adding colour, and seeding. I figured making someone completely responsible for the slab was far better than having to rely on owner builder insurance if things went wrong.
[1] See Attachment A in Concrete Flooring Secrets for more details on our original estimates.
Buy your copy now for only $19.50 by clicking the Buy Now button below, and going through to our secure download site:
