About 20 minutes east of Denver, alright maybe 15 min east of Denver is Aurora. We are talking about east central Aurora here. Kind of hidden and forgotten, this area of town has a new neighborhood. This neighborhood, formally referred to as Sable Altura Chambers is situated blocks from Sable Elementary school.
Our customer most recently purchased the home and has plans of changing the original landscape that came with the home to include a new stamped concrete patio. Now keep in mind that it is January of 2021, most concrete contractors in Denver are not pouring concrete this time of year. As a matter of fact, many contractors have shut down their practice until warmer weather peaks it’s head out. Regardless, for this customer, they would like to enjoy their new patio at the start of spring 2021. So, it is important to time the pour so that we can avoid freezing temperatures. Additionally, we do end up using blankets on this pour as we did encounter freezing temperatures after the patio was poured. Playing it safe, we decided to use blankets to insure the concrete a successful completion of the hydration process.
The Mission: Look and Feel
This is the reference that the customer had originally sent to our crew. This is the look and feel that he was looking to achieve with his new concrete patio.
Our customer in this case knew exactly the look that he wanted for his new free-standing patio. When the homeowner purchased the home six months ago, it did come with this new concrete patio. The existing concrete patio does not have the design or look that the homeowner really wanted. Originally, he had wanted for our crew to pour a free-standing back patio, it would be colored and stamped to match the reference image to the best of our ability. When it came to selecting color for this project, the customer requested that the crew select the colors to match the picture as best as possible.
Of course, the crew cannot guarantee a match, and this was explained to the customer. Regardless, his preference was to have the crew select colors. This since the crew works with these colors on a regular basis and he felt more comfortable turning this over to these concrete experts. After reviewing the referenced picture sent by the homeowner, the crew decided that a lightened recipe of “Slate” from Brickform Integral line of Colors. They decided they would go with 1/3 of the color called for by the manufacturer.
For the border, the choice was easy, the crew chose to use a color hardener, Dark Gray from Brickform / Solomon. The color hardener is applied to the border after the concrete has been poured. This hardener will give the patio the two tone look that the homeowner is looking to achieve.
Design and Size New Stamped Concrete Patio
As for the design of the new concrete patio, the homeowner was simply looking for a useable patio as the existing back patio gave room only enough for a BBQ or for a seating area but not for both. With the new stamped concrete patio, our customer will now have the room for both. Additionally the covered patio will best be used for grilling and the new back patio will serve as the seating/eating area.
The customer wanted to “round” out the corners of the back patio so as to not end up with a “square” or rectangle patio. They were looking for a little more shape than a basic square pad.
This video walks through the start, preparation and concrete pour.
The preparation for this patio is a different than a tear out and replace. This is mainly since our crew needed to excavate around irrigation, expose and address irrigation. This is typically not a factor with patio replacement.
After our crew excavates the area for the new concrete patio (sod removal and some light excavation to achieve the final elevation that we are looking for), they go to work preparing the new base of the patio. This is done by installing road base over the newly excavated area. As a rule of thumb our crew will typically install 4” of compacted road base for a new concrete patio. Situations or conditions that would change this might be a hot tub pad or extended driveway where the concrete would hold significant weight. In those cases, a thicker base and reinforcement bar would be installed.
However, in this case, for this patio a seating and eating area, wire mesh reinforcement will work. During preparation, our crew will go to work placing wire mesh. This is pulled into the middle of the pad as the crew pours the new concrete patio.
The crew for this project will form for a consistent 4” thick concrete pour. There will be thickened edge around and exposed faces, this will ensure that our new base is held under the new patio and will not be exposed to the elements. It is during forming that the crew will slope the new concrete patio. Our crew manually checks all forms for slope as well as pad thickness. Once the forms are set our crew went to the homeowner for final approval. Once the homeowner approved the forms, color and project site preparation the crew scheduled the project for the concrete pour.
Above, the video shows the site completely prepared and ready to pour. The base has been installed and compacted, thickened edges alongside the forms nearest to the fence and wire mesh reinforcement set throughout.
In Colorado, and especially in and around Denver, shifting soils are definitely a thing. Every day our team sees potential projects and a great deal of them are replacement projects. Many of these projects that we look at for replacement seem like they could have had better outcomes with proper base preparation and compaction. It is not common for our crew to tear out existing, failing concrete that is well prepared. In many cases the concrete has the reinforcement that is advisable for the particular project. It is more a consistent lack of base preparation that our crew sees time and again.
Below is an image of this project site ready to pour. The compacted base, wire mesh reinforcement is all in place and nothing has been skipped or looked past. Our crew prefers to pump most concrete patios as it gives the surrounding landscape a break and does not create more work in the end.
Above, wire mesh has been placed into the forms, this will be pulled up after the concrete has been placed so as to place the wire mesh reinforcement grid in the middle of the new pad. It is important that the wire mesh is set before the crew allows for the concrete to set. If this is not completed then the mesh can wind up at the bottom of the pad where it will offer no real reinforcement to the patio. In addition to the wire mesh, the form can be seen as well. This patio has a higher elevation than the surrounding landscape. This has created a "thickened edge" for the entire perimeter of the patio. This will require the crew to strip the forms and finish all facing for the patio. Faces are the sides of the patio that are exposed and are visible for the most part.
In the image below, a closer look at the preparation and wire mesh reinforcement that have been installed in the forms. The thickened edge referred to previously can be viewed in the close up of the newly formed out back patio. This thickened edge, it is the area between the main portion of the back patio and the forms. There, the base dips down to "zero".
We don't want to get too far off of topic here, but this is definitely a good time to explain what a thickened edge is if you have never heard the term before. What better to explain the term but a diagram... right?!? Below, a diagram of a thickened edge. If a thickened edge is not formed and the crew were to have formed a base all the way to the forms, this would leave the base exposed. This is definitely not desireable as it will allow the base of the patio to just drift out from underneath the new concrete slab! Voids under concrete creates opportunity for the slab to break or crack.
So, okay, now you know what a thickened edge is. With this in mind, in the image of the patio above, you can see that there is a space where the base drops down to zero or a little below "zero grade" and then the form. The crew will be stripping all of these forms as they stamp and finish the faces of the patio.
The Concrete Pour
Now that the crew has completely prepared the new concrete patio, it is standard practice that they obtain approval from the homeowner, General Contractor or individual that is overseeing the project. In this case, the crew reviewed the preparation, the base of the new patio and the reinforcement design with the homeowner before scheduling the concrete pour.
Below (in the video), the concrete crew places the concrete into the forms using our own ground line pump. The advantage to using the pump for a project like this is several fold.
- Number one, it alleviates the back breaking work the crew would have to do traditionally by using a wheel barrow to transport concrete. We need these guys to use that energy finishing this patio! Not transporting concrete.
- Secondly, the pump will allow for the crew to focus on placement of the concrete and more importantly they will be able to take the time to really work on the finish of the patio.
This is exactly where we want them to be focused. Diverting the crew away from placement and or finish is a move in the wrong direction. With as limited time as the crew has to complete the project it is important to save time where possible. For this particular project, the crew was able to pump a total of 7 yards in a matter of 30 minutes. If the crew were to manually place this concrete with wheelbarrows it would take closer to 1.5 hours. This is not fast enough and allows the concrete to get hot. We want the concrete placed as quickly and efficiently as possible.
After the crew has finished placing the concrete, they will go to work screeding the concrete into place and then finally bull floating the surface. After this process has been completed, this patio will have a border and it will be colored different than the main portion of the concrete patio. The border will be cut into the new concrete patio at width of around 12". Below we can see what the patio looked like after it had been poured. This is before the control joint was cut for the border. This color, is Slate. It has been selected by the customer from the Brickform / Solomon Color Line of Integral Concrete Colors. The color was applied or mixed in the barrel truck when the crew set up the ground line pump.
Before the concrete sets, the crew will apply a second color. A hardener is applied to the border. In the image below the "dark gray" border can be seen. There is significant contrast between the inner main patio and the border. Now, with this two tone colored patio we are starting to take on the look and feel of the referenced patio above.
In the photo below, the crew has started to smooth trowel the border. The crew will be smooth troweling the border as well as the main patio (once the concrete is set).
One the concrete is set, the crew will go to work smooth troweling the entire patio. After the patio has been smooth troweled, the crew will use a liquid release. They apply the liquid release with a sprayer. This release is used in conjunction with the stamp. The release allows for the stamp to imprint the concrete without picking up the concrete into the stamp. When stamping, the crew does not want for there to be irregularities with the stamp finish. Although, it is entirely normal to see some chips or areas where the stamp did not take, it is undesirable to have this be a common occurrence throughout the patio. Once the stamping has been completed, because this is a winter pour, the crew will use blankets in this instance.
It is not typical that Denver Concrete Inc uses blankets. In most cases we attempt to pour concrete where blankets are not required. In this instance, with it being a stamped concrete patio, it will only add more irrgularity in color which will lend to a more "organic" look and feel at the end of the day. So in this case, we went ahead and used blankets on this patio.
After The Concrete Patio Has Been Stamped
The day after the crew has completed the patio, it is important that they return and cut release cuts in to the new stamped concrete patio. Cutting control joints into a stamped concrete patio is irregular and this patio is no different. The only control joint cut into this patio is in the border. In our concrete patios it is uncommon to see a fracture crack the day after a pour, but without release cuts or control joints it is altogether possible to see cracking right away. Even as early as the following day.
In the images below, the crew cuts release cuts into the main patio. The finish of the stamped patio can be seen. The main patio has been stamped using the small ashlar slate stamp from Brickform / Solomon. The border has been colored "dark gray" using Brickform/Solomon's Hardener. The border has also been stamped, this was completed with a skin stamp.
A seamed stamp, like the small ashlar stamp cannot be used on vertical faces and for a border the stamps are just too large to maneuver in such a small border. Also, using the same stamp throughout would definitely have a beautiful finish, this contrast really offers an upscale finish without having to significantly increase the budget for this project.
The finish of this stamped concrete patio will be a little delayed. During the winter months, it is very difficult to find the right weather for applying the final color (Antique It) and then the final sealant. So at the time that this post is being written and published (February 2021), the patio is not finished. There has been some additional work completed at the project site. The homeowner in this case was very pleased with the patio, but did not necessarily appreciate the lack of connection between the two back patios. So after pouring this patio, the customer requested that we pour a similar border for his already existing concrete patio. Also, the homeowner wanted to connect the two patios with a walk/sidewalk between the two patios. We have completed this project and will be updating with final photos as soon as our crew is able to return and apply final color with sealant.