THE SLAB
21 July was a big day for us ... they poured the slab for the house and casita! We delayed the pour for a week in order to avoid the record temperatures of the previous week. This worked out in our favor as the temperatures on the morning of the pour were only in the high 70's F (25 C), the monsoons have kind of sort of started so the humidity was a little higher and there was a high overcast layer of clouds which kept us out of the sun until late morning. Since this was the important pour, they also started much earlier. The first truck rumbled up the hill just before 6:00 AM.
The first truck of the day!
Unlike the pour for the footers, a lot people were required for this pour as this is going to be our actual floors. So a crew of finishers were brought in to assist. The foreman for the finishing crew was Jesus (plaid shirt and straw hat). He ran a tight ship but it helped that everybody knew their part in the process.
The first pour of the day
A busy crew
A lot more concrete to pour
We ran out of parking spots up at the house site, so Nancy and I had to park down below. At least we know we have enough parking for the next Canada Day Party!
The parking lot is full!
This pour went much quicker than the footer pour last week. At one point we had truck #2 ready to pour and #3 turned around and waiting on-deck.
#2 pouring and #3 on-deck
It was fascinating to watch the finishers work the concrete. Once the concrete is poured into the forms it is spread around to roughly fill the forms. Then what looks like a long 2 x 4, but is actually a long, hollow aluminum box, is used to initially level the concrete. This is called a screed. In the below video you can see them spreading the concrete as it fills the form and then using the screed on the left side of the video.
Spreading the concrete and screeding
The next step in the process is the jitterbug. They used a 1" aggregate on this final pour and you don't want to see too much of the aggregate in the floor, so the jitterbug is used to bring the 'cream' to the top of the slab.
Doing the jitterbug
Following the jitterbug, the bull float is used to get the first rough finish on the slab. This is probably, no it is, the longest handled tool I have ever seen!
The longest handled tool ever!
While all this is going on, they were also putting a slight slope, about a 1/4 inch drop, on the outside 18" of the slab. This will ensure all the water drains off the slab and not into the house or casita.
Sloping the edges
After the bull float, they used a power trowel to refine the finisher even more. Jesus took command of this task. With the knobs on the handle he could change the pitch on the blades, thus controlling the type of finish he was putting on the slab.
Jesus working his magic
A close up of the blades
The final refining of the slab was done with hand trowels. In order to get to the parts of the slab they couldn't reach from the sides, the finishers used knee sleds to skim across the surface of the slab. These are true artisans!
Artisans at work
Throughout all this the "Boss" was doing what she does best ... documenting it all with photographs and videos. Nancy was excited to see the pour as she had to work during the footer pour last week.
Making sure the measurement for the southern
windows is correct
"We picked a good color for the floors!"
"Is that concrete thick enough?"
While the finishers were working their magic, the other members of the concrete team were busy putting in the bolts (used to hold down the wooden plank that the straw bales will sit on) and the all threads (one on each side of the bale walls) that will be used to cinch down the bales. Each of them have a 90 degree bend at one end. The bent end is inserted into the wet concrete so that when the concrete dries you can't pull it out.
Lots and lots of bolts (brown) and all threads (silver)
And just like that we had finished slabs!
The house
The casita
Since these will be exposed concrete floors, we were concerned about cracking. One way to limit the cracking is to cut joints into the concrete. This basically gives the concrete somewhere to crack so that you won't notice the cracks as much. We had to wait a couple of hours for the concrete to set up enough to safely cut the joints. Doug, head concrete guru, did the majority of the cutting with a walk behind saw. You can see the guide arm on the front of the saw. By keeping the little wheel on the front of the arm on the chalk lines they had snapped, he was able to cut a straight line. In the area he couldn't reach with the saw, like around the bolts and all thread, one of his assistants used a hand grinder to cut the joints.
Where one joint bisected another, Doug had a trick up his sleeve to prevent excess spalling (concrete chipping off the edges of the joints). He ripped off a section of a case of Coke box, folded it over and stuck it in the joint at the planned intersection point. It worked great!
The Coke box trick!
The joints area complete!
The house looking east
The casita looking east
Now the waiting begins. Before the concrete polisher can begin work on the slabs, we have to wait for the concrete to completely harden. This will take about 28 days. While we are waiting Evan will be back to excavate for and install the septic system.
Unlike the pour for the footers, a lot people were required for this pour as this is going to be our actual floors. So a crew of finishers were brought in to assist. The foreman for the finishing crew was Jesus (plaid shirt and straw hat). He ran a tight ship but it helped that everybody knew their part in the process.
The first pour of the day
We ran out of parking spots up at the house site, so Nancy and I had to park down below. At least we know we have enough parking for the next Canada Day Party!
This pour went much quicker than the footer pour last week. At one point we had truck #2 ready to pour and #3 turned around and waiting on-deck.
It was fascinating to watch the finishers work the concrete. Once the concrete is poured into the forms it is spread around to roughly fill the forms. Then what looks like a long 2 x 4, but is actually a long, hollow aluminum box, is used to initially level the concrete. This is called a screed. In the below video you can see them spreading the concrete as it fills the form and then using the screed on the left side of the video.
The next step in the process is the jitterbug. They used a 1" aggregate on this final pour and you don't want to see too much of the aggregate in the floor, so the jitterbug is used to bring the 'cream' to the top of the slab.
Following the jitterbug, the bull float is used to get the first rough finish on the slab. This is probably, no it is, the longest handled tool I have ever seen!
While all this is going on, they were also putting a slight slope, about a 1/4 inch drop, on the outside 18" of the slab. This will ensure all the water drains off the slab and not into the house or casita.
After the bull float, they used a power trowel to refine the finisher even more. Jesus took command of this task. With the knobs on the handle he could change the pitch on the blades, thus controlling the type of finish he was putting on the slab.
The final refining of the slab was done with hand trowels. In order to get to the parts of the slab they couldn't reach from the sides, the finishers used knee sleds to skim across the surface of the slab. These are true artisans!
Throughout all this the "Boss" was doing what she does best ... documenting it all with photographs and videos. Nancy was excited to see the pour as she had to work during the footer pour last week.
windows is correct
While the finishers were working their magic, the other members of the concrete team were busy putting in the bolts (used to hold down the wooden plank that the straw bales will sit on) and the all threads (one on each side of the bale walls) that will be used to cinch down the bales. Each of them have a 90 degree bend at one end. The bent end is inserted into the wet concrete so that when the concrete dries you can't pull it out.
And just like that we had finished slabs!
Since these will be exposed concrete floors, we were concerned about cracking. One way to limit the cracking is to cut joints into the concrete. This basically gives the concrete somewhere to crack so that you won't notice the cracks as much. We had to wait a couple of hours for the concrete to set up enough to safely cut the joints. Doug, head concrete guru, did the majority of the cutting with a walk behind saw. You can see the guide arm on the front of the saw. By keeping the little wheel on the front of the arm on the chalk lines they had snapped, he was able to cut a straight line. In the area he couldn't reach with the saw, like around the bolts and all thread, one of his assistants used a hand grinder to cut the joints.
Doug cutting the joints
Where one joint bisected another, Doug had a trick up his sleeve to prevent excess spalling (concrete chipping off the edges of the joints). He ripped off a section of a case of Coke box, folded it over and stuck it in the joint at the planned intersection point. It worked great!
The joints area complete!
Now the waiting begins. Before the concrete polisher can begin work on the slabs, we have to wait for the concrete to completely harden. This will take about 28 days. While we are waiting Evan will be back to excavate for and install the septic system.
So glad you're posting this blog so we can share in your excitement. It's been a long time coming, but before you know it..... it'll be home sweet home. I'm so happy for the both of you.
ReplyDeleteLet's see... the screed, jitterbug, bull float and power trowel! There's a lot more to this than I could have imagined!
ReplyDelete