Kindergarten - Herding Cats - Fighting Bad Old Habits and Ignorance

 Not sure which of the three it is. Maybe all of them?

The workers here are very hard workers, and generally kind and polite people. But, they are also VERY set in their ways. Usually, it is the people that are 40 or older who are set in their way and not able to learn anything new, or grasp a new concept, idea, or approach - not for lack of ability, but for lack of interest and abundance of ignorance. Here, it seems even worse! And it sets in already at a much younger age!

Trying to get the concrete workers to adhere to better practices is a very frustrating Sisyphus torture!

For example:

When laying blocks, it is necessary to fill the vertical holes in the center of the blocks and compact the concrete in there as much as possible. The best way I know of to accomplish that is filling the whole about half way, then using a short piece of  3/8" (12mm) rebar to push the concrete to the bottom of the brick. Then fill the hole again, and use the rebar again to compact. After about three iterations of this, the hole is really filled and the concrete in there nicely compacted.

Here, the masons fill the whole all the way to the top in the first go, then use the "palaustre" (a mason's trowel) to compact a little. The problem with that approach is, that the trowel, depending on the size, only reaches somewhere between the upper 1/4 to - in the best case - the upper 1/2 of the block. The bottom of the cavity in the block then is mostly air.

(Below are pictures of how that looks from Iris’ house. Added a new outlet, noticed jackhammer hitting such an air-pocket!

Air cavity nicely visible

Added another outlet, noticed jackhammer hitting air

I’m so glad i was so vehemently insisting on the use of rebar at my house!)

The blocks themselves are not really providing much strength, but function only as handy form to make it easier to build straight walls. The real strength comes from the concrete columns inside of the block. Now, obviously, if the bottom part is mostly air, there isn't much strength there!

Over the last week I demonstrated this problem every day about 4 times. When I observe somebody using the trowel, I walk up to them ask them if the hole is full. They say "Yes, of course". I poke the rebar in it, and after getting beyond the top 1/4 of the block it basically falls into empty space. After pushing the concrete all the way to the bottom, there is usually somewhere between 1/4 to 2/3s of the hole empty on top! Still, some workers - mostly the ones who charge the most as they say they are experienced "albañils" - just don't want to understand and continue their old ways! 

To me, it is bad enough when somebody, who calls themselves "expert",  doesn't know this! But, to continue to do the wrong thing after days and days of proving the point - now that gets me really frustrated!

The other worst practice they adhere to religiously around here is to make concrete soup. According to documentation freely and widely available on trustworthy sites it is important to give the cement sufficient but not too much water. The more water is added to the mortar, the weaker the cured concrete is going to be. So, it is recommended to keep the mix as dry as possible. And later provide water on the outside to the finished product. for a concrete slab, usually, one should ensure that for a few days it does not dry out, by spraying water on top of it multiple times a day.

Well, the problem with this is, that when the concrete mix is dry it is more difficult to work with. If you have concrete soup the likelihood of it running all the way to the bottom of the hole by itself is higher, than with a dry mix. Also, laying and adjusting the blocks is much easier when the mix is more malleable. The masons here LOVE soup! Sometimes there is a centimeter or two (1/2 an inch or a full one) of water floating on top of the mix in the wheelbarrow! Such concrete you can break with hour hand when it is cured!

I had gotten a load of blocks delivered that were made with that kind of mix. If you touch them too tightly they were breaking. Sometimes they break from their own weight, when holding them on one end! 

Imagine an earthquake hits, and your wall is built with such blocks, filled with such mortar, and in that fashion! Your wall turns into a pile of gravel!

Well, for the last two weeks, as we've been working on first the foundation slab and now the walls of the house, I have been fighting every day and all day to get the mix to be dry. The more "experienced" the person is who is making the mortar, the more often I have to send the wheelbarrow back to add sand and cement.

The same goes for the filling of the blocks! I ended up asking the least experienced persons on the site to do these tasks (filling holes and mixing mortar) - because they would obey what I tell them to do. The more experienced ones would do the right thing when they see me watch them, and go back to their old habit as soon as they feel unwatched!

The lesson I learned: Try to get unexperienced helpers, and only one or two "experts". Then explain the approach to the helpers until they understand. And the experts? Well, I have to keep a constant eye on them! Like in a kindergarten! I have two eyes, so I can watch two "experts"; no more... And just keep on watching them!

Sigh...