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Sunday, June 21, 2009

How to Build a Patio in Expansive Soil: Part I

Other than getting new windows (which will happen before the end of 2010 because we can get an energy conservation refund of up to $1500), one of the things I've wanted most for our house since we bought it was a patio in our "BBQ yard." FINALLY after over 2 years of living here and countless rainy days of wiping off muddy paws that come into the house after potty time outside, we have our patio! The only remaining dirt out there will soon be landscaped or covered up with some sort of pavers for a walkway. So my dream of no more muddy paws is close!

This little triangular-shaped yard is directly outside our dining room, through a big sliding glass door. It sat unlandscaped for two years and was dry, dusty, ugly. Because there were no plants out there, the dog pee and poop stink would linger--I will never again take for granted the billions of soil microbes that eat that stuff up in lawns! As it was the only yard visible from our pretty dining room, you'd like we would have done something with this yard ages ago. But we never did, until now. It was an embarrassing site for sure.

Last weekend my dad came up to help us create the patio. He and I designed the patio using Autocad several months ago. (The good thing about waiting for so long to build the patio is that once we got around to actually doing it, we were 100% sure of the ideal design.) Because Davis has expansive, clay-rich soil, we knew that pouring a solid concrete slab would not work--it would just crack. So we decided to use concrete post bases (that will eventually hold posts for a shade structure) with pressure treated lumber running between them. Then we'd lay pavers inside the wood/concrete border. No worries about expansive soil or drainage!

My dad made the concrete forms for the pilasters in Livermore and brought them up here--they were really cool because they had notches in them to accomodate the wood and everything.'s how we built the patio, step by step:

Friday, 6/12/09: Daddy and I went to Home Depot to buy all the stuff we needed (except concrete mix) for the patio project--sacks of Portland cement (so named because the original cement mixture resembled the smooth stones found on the island of Portland near the British Isles...or something like that), treated lumber, metal form stakes, etc.

Saturday, 6/13/09: Dave and my dad cleared all the junk out of the yard while I babysat Teo. Teo and I came over before his nap to see how they were doing.
Then, using the Autocad drawing with all the specific dimensions, they hammered stakes at the appropriate places to mark where the pilaster forms would go. String was drawn between the stakes so they could measure all the diagonals and whatnot to ensure that it was all square.
My labmate dropped off our lab's motorized auger the week before, knowing that we were going to be doing this project. Although it was only a 4" diameter auger (we needed it to be about 6"-8") and the idle was scewy, it was such a help. Much better than digging the whole thing with post hole diggers--especially when you want your holes to be at least 3' deep.
Teo did not enjoy the loud motor on the auger, so he hunkered up against my dad for comfort since I was busy snapping some pictures. He's such a cutie: as my dad said, "he's terminally cute--like he stepped right out of a Norman Rockwell painting."
They used the post hole diggers to widen each hole. And then they laughed at Ruby when she dropped her ball into one while exploring.
And yes, that's our shop vac--Dave used it to get the last bits of soil out of each hole that he couldn't otherwise reach.

By the time I got home from babysitting around 4pm, they had begun to set the wooden forms over each hole.
This was a time-consuming process because not only do the forms have to sit over each hole, but they have to be exactly level in each direction and have their centers in the exact right spot relative to all the others. Metal stakes were screwed to each form to hold them firmly in place, lest they shift when shoveling the concrete inside them.
Hunger, diminishing daylight, and no concrete mix ("con mix") prevented us from pouring the concrete that night.

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