During parts 1 & 2 we prepared our site, mixed the concrete, placed the concrete in the forms and screeded the concrete. So we now have a patio, a very nice patio. As a side benefit we also have biceps of steel and have lost about 10lbs from all the manual labor we have been doing so heck, count $20 off of this project for the money you saved by not having to have a gym membership this month! Seriously though, no matter how big or small your job is congratulations on getting to this point in the project. I know that at this point I felt like “why didn’t I just pay someone to do this for me”….then I realized I saved several thousand dollars most likely so I gave myself a pat on the back and kept going.
Sealing The Concrete Blocks
Once your blocks have set up for ~24 hours (whenever you can walk on them, which will very depending on weather so this part is subjective), you should be sealing the concrete to protect all of your hard work. You should be able to tell the blocks are almost ready when the initial sheen from the fresh concrete blocks begins to fade away. The sealant will help protect the concrete surface from the elements and make your new patio blocks last longer. We chose to use the quikrete concrete sealant after reading many many reviews online about ease of application and overall results. There are many options for sealant out there with different finishes (matte, glossy, etc…). In addition to the sealant, you will need a sprayer to actually put a nice light coating on everything and a paint roller with extension handle to spread the sealer out and get it evenly distributed. We chose to use the sprayer because it was easier on us and we could use exactly how much we need, but you could probably also just use a paint tray and spread it around. Buy the cheapest paint roller, you will not be reusing it and the concrete surface does not really care if it is “Extra Smooth Finish”. I do not have any pictures of this application process, but it is very simple. Spray the sealant on and simply use the roller to push the sealant into all of the joints and cracks that you can get to. It may look slightly foamy at first, but just keep spreading it around and that will go away. Be sure to apply the the sealant thinly at first, you are just applying enough to let it soak in and create a slight surface film as you don’t want too much on the surface that it does not soak in completely. As a side note for this process, you will want to do this sealant process after every work session. Our patio project took many many many different work sessions over the entire summer when we had free time on weekends so we repeated the process for every set of new blocks. It literally only takes about 10 minutes to “paint” the sealant on. Remember to clean the nozzles off the sprayer each time or you will be taking time at the start of each session pealing out little strings of hardened sealant before starting.
What To Do With The Space Between The Blocks
So by now we are on the home stretch, it even looks like a whole patio now that you could actually use. The last step in the process, the joints and spaces between the little blocks in each form. At this point we had several options and sometimes it depends on the particular pattern that you chose at the beginning of the project. You could leave the patio the way it is if you really wanted to, but you should expect weeds and on things to eventually grow up between them. We saw some people with similar systems on the internet who actually just filled in all of the joints and patterns with dirt and planted grass seed, moss or over low growing greenery for a more mixed nature look. We saw some people actually just poured straight cement between the joints to fill the major joints between blocks (we worried that this might cause issues with freeze thaw in the winter so we skipped that idea). We also saw that some people filled in the joints with sand to make everything somewhat level. In the end we were having a very difficult time trying to decided what to put in. We personally felt the gaps in between the joints were too wide to leave nothing in them, but we didn’t want the maintenance of grass or sand with ants crawling everywhere. Then we found a different idea via the vast wonderful internet….polymeric sand.
Oh the wonder of internet research. Gone are days when you only had the 1 guy at your local hardware store to ask advice, now the internet connects you to millions of people who are willing to show you different ideas. Polymeric sand is essentially sand that had an extra polymer chemical in it that allows it to remain like regular sand until you activate it by applying water. Once it is soaked with water the first time it hardens and creates a semi hard layer that makes it harder for weeds, ants and other pests to break through. It also is much much better at holding up to rain storms. One of the main reasons we did not like just sand was that we had heard horror stories of it washing out of the joints after big rain storms. After all of the work doing this patio we did not want to have to reapply sand every time we had rain. After having this polymeric sand down for awhile now, we can say that it is far better than regular sand, but just don’t expect it to be rainbows and butterflies as it still has a few draw backs.
Applying the polymeric sand (PM) is straight forward, but you do have to be careful. Essentially the steps are 1) spread sand into all gaps with broom. 2) use a leaf blower on low and almost parallel to the patio surface to blow off excess sand. 3) apply a light coating of water several times.
Sounds simple, but lets face it when is anything as easy as it sounds. First of all, you really do need to sweep it evenly into all of the surfaces. We chose to bring it to level with the top of the bricks everywhere, but you may want a different look that leaves a little more reveal on the edge. Second, it is very important to remove all of the sand from the surface of the blocks and only leave sand in the gaps. We saw complaints from some people saying that there is a haze on top of the blocks if you leave anything on top of the blocks. We painstakingly brushed off the top of each block after leaf blowing the entire thing. While leaf blowing, make sure not to point it down at the blocks too much, its sand, it WILL blow away. If it does blow out of a gap, fill it back in now, you will not be able to later easily.
Lastly the water….this is the trickiest part. Too much water and the sand washes out before setting up, too little and you only soak and activate the top portion of the sand instead of all the way through the entire amount. We used our garden hose sprayer and went for something akin to a very light rain. We simple walked all around the patio for about 5 minutes until everything was soaked pretty good. The directions say to do this 2-3 times I believe at 15 minute intervals. Once this is accomplished leave the sand to use the magic polymers and harden.
Congratulations your patio is now complete! Stand back and admire the patio, it is awesome! Of course you should level the edges and replant some grass seed around the outside, but the hard part is all done, you can break out the deck chairs and have some friends over for a party. Or if you are crazy people like us you think to yourself, gee how can I continue this awesome feeling of doing even more work on the back patio…..of did you say build a Pergola and a concrete table to go with it…..yeah that’s what we thought too! You can read about those adventures coming soon.
Follow Up And A Few Lessons Learned!
- Be careful with the concrete. Dust from mixing and concrete drying on exposed skin are not good. Wear protective gear like dust masks, gloves and eye protection to avoid problems.
- Many hands make light work does not really apply when dealing with concrete, but help is great. We had extra helpers in the form of the weekend warriors. While they were not allowed to do any heavy lifting on this job, it was a great help to have them clean tools or hold screeds when we were dealing with actually lifting heavy loads of concrete or placing the concrete.
- Cleaning tools is essential. We cleaned all of our tools at the end of the day including all hand tools, buckets and even the mixer. It is important to keep anything you plan on reselling clean and new looking, but mostly it helped keep it all in tip top shape day to day.
- Clean your screed every block you do with some water. We found that a slightly damp screed piece of wood make the screeding much easier. If the concrete ever started to dry on the screed we fund that the finish would become uneven and not look as good.
- We did the patio over the course of many weekends. Sometimes we would come back and find the form would not fit well next to a block we had previously done and this would lead to the row being slightly out of alignment. To fix this issue carefully inspect the previous blocks, more than likely there are small bits of concrete on the bottom of the block that may have squished out (technical term) from under the form. Just take a hammer and an old screw driver and carefully chip these pieces off the block to snug the form up better.
- With our particular pattern, we chose to rotate the block each time we placed it 1/4 turn to randomize the pattern. If you choose to do this as well, just make sure you check this each and every time you place the blocks down. There is 1 block, yes 1 block on our patio that we missed and it bugs the crap out of me! luckily for us, it is under our table now so no one will notice.
- Once these blocks are set in place and hardened the only realistic way to get them out is to break them up, so be careful when placing them the first time.
- If there is even a possibility of rain showers within 24 hrs of placing your bricks, cover them with tarps once they are dry enough to cover. You do not want the rain ruining all of your hard work. The first set of bricks we did got slightly damaged when a small shower passed by 12 hrs after we were done. The vast majority were fine, but the set that was directly under the roof drip line got slightly damaged as the rain off the roof was slightly more concentrated than the rest.
- Use the cooking spray liberally on the forms and repeat rinsing and reapplying cooking spray every 2-3 times they are used. It will make getting a good surface much easier.
- If you run into areas where the polymeric sand does not adhere (we are having issues with the drip line from the roof) we have heard that some people will put down a small bit of regular cement then cover it with the polymeric sand to give a uniform surface look. We are planning on trying this application this summer along the drip line that keeps washing out.
That is all for the Affordable Concrete Patio Series for now. We hope you enjoyed this adventure with us. Please join us on another adventure soon.