Today was the first day of installing the footings on our Earth Sheltered Umbrella home. You can find the video here.
After the initial excavation, we tried to stake out the basement but the hole wasn’t big enough and we had to call back the excavators to dig a little bit wider (see the last post). When I showed up on Friday (after a nearly a week off the site), I found that it was excavated well enough most of the way around, except on the north east side. On the west side, they had to excavate past the side of where the garage footing would have gone. The plan B had been to setup the footings for the basement and garage at the same time, but the over excavation cut into dirt under the garage, so we will need to save that for after the excavation. Plan C was to just form the basement footings and consider that practice for the rest later.
The crew from Dysert Concrete arrived on site around noon. There was a range of experience from one who had worked with Doug Dysert since they were both children, to the new guy who had started that week. No one on the team had ever done curved forms before, but they were all up to the challenge.
At one point, Doug sent the new guy to get the majibulator from the front of his truck. The new guy scrambled up out of the hole and got half way to the truck before Doug called him back and told him that there was no such thing as a majibulator.
Doug had brought 12 inch lap siding for the curved portions of the form and 2x12s for the straight parts. My computer model had made it pretty easy to estimate how much of each material we needed, but due to the change of plans (not doing the garage), I ended up with some extra materials on site. The lumber yard was out of stakes Doug bought 1x4s and sharpened them on site.
The team decided that Sherri and I had done a good job on the stakes (within a quarter inch and enough extra ones to capture the shape) so they used them directly and started forming within a few minutes.
Doug had brought his copy of my plans and we referenced it regularly. It was a bit of a hassle because the plans incorrectly showed the footings as 1.5 ft wide in the main view (the more detailed views correctly showed 2 ft). This caused at least one mistake where we made one of the piers 6 inches wider than it needed to be. The plans also did not include the extra footing bits that the building inspector wanted, so we had to remember to add those.
Doug had to leave part way through the afternoon for another appointment (so his crew will have work all summer), which left me responsible for the layout. Along the way, I made several mistakes that I realized right after the boards were cut and nailed into place. Some could be easily undone (such as the east pier where I just cut a board too long for where I intended it, but it still fit perfectly in the next spot. Other mistakes were not worth fixing and just added a little volume to the piers. The other guys (Baudillio and Jose) were pretty patient with me and only chucked a little when I would say, “No, wait, thats not right.” When I slowed down I made fewer mistakes. In total, I figure my errors only added about 4 cubic feet to the 18 cubic yards needed for the footing. That is less than 1 percent. (total concrete volume of the basement footings is 18 cubic yards (486 cubic feet) or about 73000 lbs).
I was very careful to place the inside boards so that each would only have 1 side and 1 end against concrete. This will make it much easier to remove them later.
The north east side of the site (top right corner of the scene, mostly off camera) was not excavated far enough and the guys had to dig it out manually… They ended up re-digging it numerous times because they didn’t throw the dirt in the right place (twice) and because the sand wall behind kept caving in and dumping more sand in the area. In the hot sun, it became a “laugh so you don’t cry” sort of thing, but we managed to get that last footing in and everyone left by 5:00 PM.
I noticed that when the guys wanted to keep their water jugs cool, they buried it in the cool earth. They didn’t build a little wooden box around it. Just sayin’
I also noticed that a couple of the guys put oats in the bottom of their water bottles… I wasn’t sure if they were eating those as a snack while they drank or had some other reason. The “new guy” asked about it and the others laughed and asked him if he ever had oat meal. “Same thing”, they said.
The laser level Doug brought was not working, so we just put the forms in for now and will need to come back next week to level them and add the ton (literally) of rebar.
When it was done and the guys were packing up, they said, “At first we thought the curves would be harder, but it all went pretty easy.” They all took pictures. I assume they don’t think most of their jobs are photo worthy.
If I did it again, I would use a saw table to make straighter cuts for the boards. The free hand cuts were pretty sloppy and made it harder to get the 90 degree angles for the piers. I guess it was good enough for footings work, but I don’t think it would have been any harder to make the more precise cuts and may even have made it easier to assemble and level. The hardest part would have been getting the table and power down into the hole.
Monday is rebar day, and hopefully I can get the building inspector out there on Wednesday so we can still pour this week… Now I need to think of what to do with the extra concrete. Any ideas? I am thinking a bucket rocket stove could use up a little.
Saturday, our kids each had soccer games, one after the other. Each of my boys won their games (3 to 2 and 5 to 3). By the time the games were over, it was mid afternoon, we dropped them off with their grandparents and headed out to survey the basement. We were using a builders level that I rented, again. We had to do the job again because all the previous stakes were dug up during the excavation. Well, I should say most were dug up. Sherri had run some extra stakes further out so that we could re-establish the location of the center of the house. The excavators had been careful not to disturb those markers.
When we got there, it was kind of cool to be able to drive up our new driveway… Its the little things ;^)
We started with the long line that Sherri had marked out before the excavation. We tied some masons line between the stakes that she had placed 50ft on either side of the center (the excavation was about 60 ft across). We tied a plumb bob to the mason’s line at the middle point and let it hang into the excavation. The sand was also very soft and rough, so I spent some time flattening the area, especially around the hanging plumb, with my 10” tamper. I then positioned my marked concrete paver (90lbs) centered under the plumb and lined its etched angles up with the mason’s string overhead. Then we setup the builder’s transit over the paver (I finally have that setup process figured out after three rentals). Again, I used the overhead string (and the lines etched on the paver) to orient the transit. It took us about an hour of setup before we placed our first stake, but once we did, the rest went fairly straight forward. Since most of the key points for this design are positioned radially from the center, we just needed the transit for the angles and a measuring tape for the distances. This marked out the centers of the edges, then we offset these stakes by one foot (half the width of the footing) to get the true outer corners. In one corner, we use some Pythagoras (3-4-5 triangle) to square things up. We also put a lot of “extra” stakes in to make the curved shape clearer and topped it off by tying string along the perimeter of the footings. We actually had brought surveyors paint, but it didn’t work well on the sand.
The pit had not been excavated far enough and I had to do some manual digging along the way. The soft sand was easy to dig (I did all the work barefoot and pretended I was at the beach) but as I dug, the sandy wall would cave in and give me more to dig. I couldn’t throw the dirt out of the hole, so I tried tossing it “out of the way”. But I didn’t put it “out of the way enough” and I had to dig some of the same dirt again when I got to the next stake. Sherri thought that was funny. There were a few areas that had so much sand I just gave up and stuck the stakes in about where they would be. We called the excavator to come back and widen the excavation. That was a bit disappointing because it meant we would need to delay the start of the footings. Anyway, we got it all staked out by 9:20 PM (just before it got dark), but it was probably closer to 10:30 PM before we completed the long drive back and picked up our kids (an hour and a half later than planned), so we appreciate that my in-laws were merciful and hope they will still help us out next time ;^).
Hopefully the Excavator will go back and take care of the over-dig without disturbing these stakes or the centerstone marker (paver) too much and we can get to work on the footings. I found out that my footings guy uses a “Total Station” builders transit. It has a computer that does all the trig for you. We will let him stake it out next time. I just need to figure out how to transfer my drawings into the right format.
Friday, I met with the building inspector (Dale) to discuss his notes, especially about the footings and “special 3rd party inspections”. I also wanted to discuss the alternative to the step footings that my concrete footings guy wanted.
Dale started the meeting by saying that he had read my email (which included a detailed description of “frost protected shallow footings” and all the codes related to them) and that frost protected shallow footings were fine. I guess the plans simply had not been detailed enough to show that they were “frost protected”. Great. We got thru his other notes just about as quickly. I told him I would happily do the concrete encased electrodes, but since my footings should stay dry, I would also be putting in conventional grounding rods. He said, “of course.”
Then we discussed the “special 3rd party inspections”. He simply didn’t feel qualified or comfortable signing off on those parts of the construction. These included things like my precast concrete ribs, the rebar in the vaults and the shotcrete. He wants me to hire a 3rd party engineering company to certify that these are built correctly. Of course, this will be additional expense for me.
I tried to explain that I had already paid the engineer a lot of money to certify the design of the rebar and that it was normal to trust the strength of the concrete from the mixing truck. All the building inspector had to do was compare the engineers instructions with what we did. The inspector was not quite convinced, but said I could hire my previous engineer to help him with the inspection. Unfortunately, my original engineer (Ken) has closed his practice. I did try contacting Ken anyway and he told me he couldn’t do it. My inspector gave me two other large engineering companies to contact. The first, PSI USA, told me they wouldn’t work on a residential project and the other (SME USA) has simply not got back to me (it has been more than a week as of this writing). I asked my architect for suggestions and he gave me a name, but I have not managed to call that engineer yet (I have been traveling for work myself). I spoke with my shotcrete guy (Nate) to find out who he had worked with. He said that building inspectors never have trouble inspecting his pools. My inspector had already said this is different because the pool is up against earth, the water has no where to push the concrete. In my house, the earth is trying to push the concrete down onto peoples heads. Nate said that special inspections are sometimes done for large commercial jobs, but it would really cost me, both for the inspection and for his crew to make the test panels (tested destructively).
The notes Dale made on my plans also included a list of “additional” inspections. These were additional inspections that he wanted to do because my construction was so unusual. They included inspections when I set the concrete ribs, added the waterproofing umbrella, etc. I got the impression that I would not be charged for these, but maybe I am naive. I will ask directly the next time I get a chance.
Last, but not least, I asked about Doug’s plan to change the step footings into doweled footings over fill. Dale said he didn’t like footings specified by the engineer because they had a sloped bottom. He said footings should always be flat on the bottom (which does make reasonable sense even if sloped footings are actually approved by civil engineers.) He said Doug’s plan was fine, but I needed to extend the lower footing out by a foot and put a pilaster on it to better support the doweled footing. I asked about the fill and he said the footings could span a 2ft section of fill, but any more than that and I would need the fill to be “engineered”. I guess I will need to get that done, hopefully it is not to expensive. At least my sand should be easy to compact.
In the end, I updated my model to facilitate communication with my footings guy (Doug, sounds more like the name of an excavator doesn’t it?). I hope to meet with Doug tomorrow to come up with a plan of attack. I have agreed to start with just the basement footings and get the basement walls up and backfilled before working on the other footings. It changes my schedule a bit, adds an additional concrete pump rental and an additional footing inspection, but it does seem easier than trying to work around that sloped sandy excavation. Including that basement in the design really has complicated things. I will ask Doug about doing the garage footing at the same time so I can start on that Quonset hut sooner.
After the initial excavation, we tried to stake out the basement but the hole wasn’t big enough and we had to call back the excavators to dig a little bit wider (see the last post). When I showed up on Friday (after a nearly a week off the site), I found that it was excavated well enough most of the way around, except on the north east side. On the west side, they had to excavate past the side of where the garage footing would have gone. The plan B had been to setup the footings for the basement and garage at the same time, but the over excavation cut into dirt under the garage, so we will need to save that for after the excavation. Plan C was to just form the basement footings and consider that practice for the rest later.
Doug had brought 12 inch lap siding for the curved portions of the form and 2x12s for the straight parts. My computer model had made it pretty easy to estimate how much of each material we needed, but due to the change of plans (not doing the garage), I ended up with some extra materials on site. The lumber yard was out of stakes Doug bought 1x4s and sharpened them on site.
