Tuesday, May 27, 2014

A Chip Off the Old Block

Since last Tuesday I've been on assignment at Sandhill, helping my old community construct a 12,000 gallon cistern. While it's gratifying to know that I can still do the physical work, lifting and setting concrete blocks for eight hours the past three days has been exhausting. I've been easing out of bed each morning, not jumping.

Still, the work is going well. After having done a few of these projects (I've previously built two septic tanks and one cistern using a poured slab floor, block walls, and a poured roof) you learn mistakes to avoid and better methods of production, and this project has gone more smoothly than any I've done before.

1. Dig a big hole. More than enough to be able to walk around the work on the outside, the excavation needs to be able to accommodate the possibility of cave-ins without disastrous delays or necessitating that work will need to be redone. In this instance, the footprint of the cistern is 27' x 8.5', so we had the backhoe dig a hole 43' x 25'. (It's a bit eerie to be working in a nine-foot hole where you can see strawberries blooming above your head on the edge of the undisturbed garden—kind of a mole's eye view.)

2. That said, you need a tight enough hole that you can get a cement truck close enough to drop the concrete for the floor (with a minimum of chasing wet concrete by hand—talk about work), yet without running the risk of the truck collapsing the soil under its approach and sliding into the pit. (I've never seen a cement truck tip over with a load on, but I'm sure it isn't pretty—most especially when it ends up in your backyard.)

3. Much of the art of construction is learning when you need to be picky and when you don't. There are certain errors, such as the levelness of the floor or the squareness of the walls, where being a half inch off over 25 feet can haunt you the remainder of the project. Others, such as a sideways curve in a slab form or a crack in a concrete block don't matter a hoot.

My crew is young and eager, yet inexperienced working with concrete and block. Thus, when they see a slightly damaged block they ask me whether it's usable or not. Experience allows me to think ahead to how the block will be stressed and what it will take to overcome the defect. If a block is chipped, can it be hidden by placing it next to a pilaster; how much surface boding will it take to smooth over the hole? I can see ahead to make these assessments, and they haven't a clue. 

It is worthwhile to be very precise about the placement of 90-degree angled rebar when the slab is being poured, such that the portion that extends vertically out of the slab will fit nicely into the cavities of the concrete block. If it hits the webbing of a block it's a bitch. Because I'm invariably too busy during a pour to attend to rebar placement (I'm usually running the screed board), I've learned that I have to set up a simple system that can be done right by someone who has never poured concrete before. I finally figured one out and all the bars were placed correctly. Hurray!

As the only experienced block layer in my crew, I insisted on placing every one of the 52 blocks used in the bottom course in a cement-rich mortar bed to correct any issues in the levelness of the slab. If there was going to be a problem with how level the walls were, I wanted it to be my fault, rather than falling on the shoulders of someone who was laying block for the first time. This care paid off in the smoothness with which we were able to lay up the succeeding courses. Sometimes you need to go slow for a time, so that you can go faster later.

After seven days on the job, I am enjoying a day off (and so is my back). In fact, that's why I have the time and energy to post this blog entry. I week from today I leave for two weeks on the East Coast and my goal is to have the walls completed and ready for backfilling before I board the eastbound Southwest Chief June 3. As of today the walls are half up (seven courses of block have been laid and grouted, with seven more to go).

If we can avoid a serious cave in for another fours days, we should be golden. Then I can form up and pour the roof when I return, when no one will be holding there breath during a heavy rain.

I enjoy projects like this:
o  Unlike most of my group dynamics work, it's clear at the end of the day that you've accomplished something. (With group work, progress can be subtle.)

o  I enjoy working with my hands and using my body. (Or at least I used to. Every year it gets harder to lift full bags of cement, or maintain a spring in my step while schlepping buckets of grout.)

o  After 40 years of homestead living, I've learned quite a bit about working with concrete, block, brick, & tile, and it's a joy to put that knowledge to use. Even though I no longer do all the heavy lifting, I can still teach the techniques and lay out the work.

o  It's satisfying to pass along practical experience to an interested younger generation. I've received a good bit of this kind of mentoring over the years and it's time to pay some of it back.

It's amusing to realize that these days I'm the oldest block, whose health is most chipped—and yet I'm the one who's relied upon to determine whether chipped blocks are still serviceable. There's a symmetry about it that's pleasing to me.

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