Whenever cement was delivered for sidewalks, or a stairway, it always seems that there was cement left over. In one case, the cement company had a full yard of extra cement that they would give me, if I could take it. Of course I would take it, I said. This meant quickly slapping together forms in a variety of places where cement would not be a regrettable addition. Consequently, I ended up with an odd extra outbuilding that had cement walls around the exterior up to approximately five foot high. The walls were ugly, as we were in a hurry to pour the cement and always had the other “original” project, which needed finishing with fresh cement, too. No problem, I thought, I’ll just cover it with rock later.
Well, later has arrived. This spring, we had MRA Construction put a roof on the building and I am very, very pleased with it. Milan, the owner, was also my drum instructor in high school, so he knew what to expect and was exceedingly patient as I explained that I wanted a special roof line. We have double glass doors that view this shed, and I did not want to be looking out at an albatross every time I passed those doors. The extra curve in the roof adds a whimsical detail that I am thrilled to see. It was definitely worth the small bit of extra labor and materials.
So, with the roof completed, it was time to address the siding. Ken suggested we try a different method of doing the rock work – namely by smoothing the joints of cement. This is unlike the finishing technique I used on the main house. On the main house, the joints are rough. It’s not that I didn’t appreciate a more “polished” finish, it was that I had my plate full learning how to do the rockwork and anyone suggesting I not only learn it, but learn to do it beautifully on the very first project, would have been limping home…smarter for the experience.
Ken, to his credit, was persistent. He really, really, really wanted it to look good. So, I opted to try smoothing the joints immediately after removal of the slip forms. This proves to those of you trying this method that adding the extra finish is not only easy, but highly worth the extra trouble, because you will not have to revisit the joints later to grout them.
So, here’s the short sheet on this process. 1) You pour the rock and cement in between the forms, with the rocks cinched up close to the leading edge, cement oozing behind and between the rocks. 2) You leave the cement to cure for 4-5 hours (depending on the weather). I’m talking about Rocky Mountain summers and falls. I’m also talking about a medium-stiff batch of cement to begin with. If you are pouring soup into the forms, it may take a little longer.
3) You remove the forms. Your result will look very rough, like shown in this photo, at right. Don’t panick. At this point, you will scrape, with the back of a hammer, or with your husband’s new iPod (just kidding) the extra cement off the rocks.
4) You will leave a smooth joint that can then be left to finish curing. You do not need to do anything else to this concrete if you are happy with the joints. If they still appear rough, you can take a paint brush (a stiff one), add some water and paint over the joints.
When you finish, you will be left with joints that look beautiful and you will exclaim, “Wow! That was easier than it looks!”
Out here, we are racing the weather. It’s cooler each day as we approach winter. I had high hopes of completing this shed before spring so that I can add a chicken pen to the north side of it and have fresh eggs soon. I’m not sure that I will hit my marks on completion time. I had counted on a teenage boy’s help. That was my first mistake! (Just kidding, again. Ben has been a fine helper. He’s just very busy in school, tennis, contemplating his navel,…you know, the hard life of being a teen.
I keep telling him, this will be a GREAT skill to carry into his adult life. He will be able to build his family a fabulous home with the knowledge he’s gained. Instead, he’s still hoping to win the lottery and hire others to do such work. Toward that end, I wish him luck. It didn’t pan out for me and I ended up doing it myself. But, if he can make it work, who am I to stop him?
Here’s a shot of Ben chipping off the unwanted cement. The extra cement, which falls into his hands, is still wet enough to shove into gaps along the seams between the rocks. The old saying, “Waste not, want not,” is true around here. If you look below Ben, you will see the older, cured cement with the finished, smooth seams.
Lastly, if you have the unfortunate experience of having any rocks pop out as you are removing the forms, don’t panick. If it is just one rock, it can be re-glued into place using a masonry glue made for the purpose. In all the rock work we have done, we have had less than three rocks pop out, and usually it was along the very top edge where I did not apply enough cement to adhere the rock into place. Use the glue, replace the rock, let it cure properly and then mortar around it as usual. *Save the rock that falls out. It will fit the hole perfectly. If you try to fit another rock, you might regret it later when the replacement sticks out of place and draws attention to your accident.
Hope this helps on your wonderful projects! I will try to post photos of the finished project once we have completed it, which does not look like it will be the fall of 2009!
To see “Slipforming, part 7 – “Murphy’s Law, a constant companion,” click here.