Thursday, January 27, 2011

4. Foundations


The story of the cement work on my house should serve as a cautionary tale about choosing your contractors carefully. My first concrete crew had just done a very large commercial building, and apparently lost a lot of money on it. They saw my project as a way of getting back into the black. This was just the first example of what has become a recurring theme -  contractors assuming that someone who is attempting to build a house like this has unlimited resources. Anyway, a large crew started work, and it was only when I got the bill a month later that I found I was being charged $60 per hour for each of those guys. Now I have nothing against workers earning a decent living, but why would anyone ever become a policeman or fireman or teacher if they can earn $60 per hour carrying rebar? Our resources were being drained at an unsustainable rate.

But that's not the worst of it. The crew spent a couple of weeks building the complex forms for the foundations around the front part of the house, and it was almost time to start pouring concrete.  Luckily, my General Contractor had a soil engineer test the ground under the footings. Well, his 3-foot probe practically fell into the ground.  "You can't pour foundations on this stuff, it's all just fill and tree roots.  Your cement contractor should have known about this!"

So, all those foundation forms had to be dismantled, and the ground had to be dug down another 8 feet, to solid bedrock. The forms were then rebuilt. I suppose it could have been worse -  at least it was caught before any cement was poured. The concrete work for the rest of the basement went smoothly, but when I found that the cement contractor was unwilling to refund anything for the mistake, I fired him.  I later found out that many people in the area had similar stories about the guy.  He has since left the state.

Contractors like to work on a time-and-materials basis, but that essentially means a blank check from the homeowner. I learned my lesson -  get at least a ballpark figure for each job, and ask for references.  The second cement crew had good references and much lower prices.

The way I'd always seen foundations done before is to dig trenches, build the edges up with wood, add rebar and pour the trenches full of concrete. Not so, here - there were no trenches. Instead, large areas were scraped flat, then topped with a foot of compacted gravel. The forms for the footings were then built on top of this pad and rebar was added.

After the foundations were poured, the forms were removed and the areas in between the footings were filled with gravel, which was compacted before pouring concrete floors on top of it.
Here's the wall that was necessary to bring the foundations from the footings back up to ground level after the front of the house had to be re-excavated. Remember, the top of this wall just gets us up to the level of the basement floor. These walls are about 8 feet high, and 18" thick. It's almost like building a whole house which will be buried and never seen again. With the new cement crew, we were back to forward progress, but our finances had been severely depleted by the first crew. It was no longer assured that we'd have enough money to finish the house.

4 comments:

  1. That's amazing about the guy who had lost the use of his legs. Quite the opposite of your experience with the first cement contractor! - It's no wonder that you came to the conclusion you did about, "If there's anything you can do yourself, do it yourself."
    When I look back, there are very few occasions where I felt the benefit of letting someone else do a job for me. But when you do find someone, they usually are worth their weight in gold!
    Is all that space in the foundations sealed off and never going to be used? - If there is enough headroom couldn't you make some use of it? - Or would there be a dampness problem due to being below the damp-proof course? - If not used, will the space require ventilation in some way?

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  2. I'll try to cover all your questions in today's post - Basement Floor.

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