Thursday, September 29, 2016

The Walkout: floods and forms

This is a post about the walkout basement at our house, which has been a kind of ongoing source of drama even since I moved here. The picture below is one I found after rooting around in the Photos app for about 20 minutes. It doesn't show the full walkout, but you can see the part of the basement door, retaining wall and sunken entrance. I took this photo from the top of the five steps going down to the basement door.

The walkout basement was a pretty nice feature of the house and I kept my music stuff there - a lot of keyboards including, for a while, a beautiful Hammond B3. From the basement, you could look out the french doors to an unobstructed view of the back yard.  There was a big lilac tree growing right outside the door, which you can see in the photo, and a pear tree, and it was a really nice place to be in the summer especially.

The problem was that about once a year in the late summer we would get a really heavy rainfall, and it would rain for two or three days and things would get so waterlogged that the sunken entrance of the walkout would start to fill up with water. It never got to the point of flooding the basement, but there were at least a couple of times that the water came right up to the bottom of the door. The basement had a hardwood floor, but it was raised up on sleepers, so although I expect there was some seepage from time to time, things were mostly ok, as long as when the massive rain storms hit I had a plan and was prepared.

I knew that this could be a potential problem, so the first time we had a big rain storm I had a couple of buckets and spent a couple of hours in the middle of the night bailing water out of the walkout. The next day I went and got a submersible electric pump, and connected a garden hose to that, and it emptied out all the water in a matter of seconds. After that it was pretty easy to get water out of the walkout, but it usually meant furkelling around with a pump and hose at 2 o'clock in the morning, which for some reason is when the rain seemed to peak.

Anyway, the rainwater getting into the walkout was a pain, so one of the main objectives for renovating the house was to excavate around the whole foundation, waterproof it, install weeping tile, and build a better concrete retaining wall around the walkout so that rainwater wouldn't get into the walkout stairwell.

For quite a while during the construction we had an open pit at the back of the house where the excavator had exposed the foundation but had not backfilled it yet. More excavation was needed to finish the walkout but our first builder, Bramel Developments, had run into some issues with the excavator, Ken Brown, who had put a lien on our house after not getting paid what he thought he was owed.  If you know how construction financing works, you can't have liens on your house or the lending institution will stop lending you money for the work.  I did a little research and found out that Ken Brown has been in the business for a long time and he doesn't screw around.  A couple of the cheques he'd gotten from Bramel had bounced, and in hindsight I can see that our builder was trying to cut a lot of corners and held off on doing the full walkout excavation.  He billed us the full price for excavation, and promised that Ken Brown would be back to finish the walkout in the spring, but that never happened, and who knows where the money went.

So we had a big pit behind our house for a long time. During the summer, this was ok. But as we got toward fall, and into the rainy season, I started to get pretty apprehensive that we might get a real deluge and that without any retaining wall whatsoever, the pit could fill up with water and flood the basement, which we had just finished drywalling.

Sure enough, right near the end of August we had a rainstorm to beat all rainstorms. It poured all day and then at night it started dumping buckets, and I knew I needed to go check on the house. It was a Friday night, and our new contractor, Michanie, had finished up that afternoon and was away for the weekend.  When I got to the house it was dark and raining hard and thundering. Sure enough water was filling up the pit behind our house and rising fast.  The little pump that I had used in the past had been broken by Bramel's crew so I couldn't use that. Instead I found a bucket and started bailing.  It was a frantic effort. At first I seemed to be making some progress but as the minutes went by it started raining harder and harder. I bailed as fast as I could, almost in a panic, trying to keep the water from reaching the bottom of the basement door and flooding in, but it was no use.

I made a frantic call to Michanie and got Chantal on the line, who suggested that I could go to Home Depot and rent a pump to get the water out. She kindly phoned one of the nearby stores and confirmed they had a pump available. As we talked, rain got in my phone and it quit working.

I would have loved to get a pump from Home Depot but it was a full on state of emergency. The water kept rising and I could see it gushing and streaming from beside the house straight down into the pit.  I also noticed, for the first time, that our neighbor had the downspout of his gutters leading into a hidden drain pipe which went under a gravel path and emptied straight into our property. The water was shooting out of his gutter drains straight into our walk-out pit!

At this point I just said "&^%$ it!". I could see that my efforts were futile, I was completely soaked to the skin, and the water just kept coming. I left everything, got in the car and raced off to Home Depot, got there 5 minutes before closing, rented a big pump and hose, and raced back home.  The pit was alarmingly full of water by the time I got back, but by that point I was past the point of panicking, just sort of morbidly resigned to dealing with the mess and doing whatever damage control was needed after.

Setting up the pump was easy enough, but getting electricity was another matter. There were extension cords on site, but none of the outlets were live, except on in the basement, so to get power to the pump I needed to crack open the sliding patio door to the basement and feed the extension cord through.  The water was already above the base of the door by that time, but I had no choice, so I just opened the door and let the water pour in onto the concrete floor while I fed the extension cord out and got the pump plugged in as quickly as I could. Now, when you're dripping wet and it's raining like a typhoon and you're standing in 18 inches of water, plugging in an electrical device is a little unnerving. There wasn't much I could do about it. Fortunately I didn't electrocute myself, the pump went on, and the 4 inch hose went completely solid as water started shooting out the far end like a jet. The pump was a thing of wonder. Within just a minute or two it had completely emptied the pit and was gurgling away in the mud.

With the pit now empty of water, I disconnected power to the pump and turned my attention to the neighbors gutter system that was draining straight into the walkout.  I grabbed a bunch of rocks and an old tshirt and whatever else I could find, and tried building up a little barrier wall to divert water from beside the house and from the neighbors gutters, and channel it towards the backyard. Then I found a big sheet of plastic and tried to attach it to various points at the back of the house, where there was some scaffolding, so that it might keep out some of the rain.  Then I ran a couple of extension cords from the basement live outlet up to the main floor and out the main-floor back door, so that I could close and lock the basement patio door.  The pump I'd rented can actually be left running dry for a few hours without burning it out, but I unplugged it and went home.

It was probably close to midnight by the time I got home, but shortly after that I got a message from Chantal at Michanie that they'd been by the house to check and there didn't seem to be any damage. They'd been at a family event, but came all the way back into Ottawa after midnight to check on things. It goes to show how much they cared and were willing to go out of their way to help. The next morning when I got back to the house, I saw that they had set up two huge blowers in the basement and a commercial dehumidifier.  These machines move a massive amount of air, and are used mainly by commercial drywallers. It seemed like these machines had gotten the basement floor almost completely dry overnight.

Following this near disaster I spent most of the rest of the weekend rigging up a better tarp over the walkout, building up a better temporary retaining wall and channel to drain water away from the pit, and getting a sump pump with a flotation valve to put in the pit in case water filled it up again.

Setting up the sump pump was an adventure in itself that involved a few trips to Home Depot.  And to make matters even more interesting, through all of this battle with the rain water, my neighbor who had been secretly diverting his run-off through a hidden underground pipe onto my property for the past 15 years decided that the water infiltration he experienced through his 50-year old, non-waterproofed foundation wall, was somehow my fault, and he got very, very nasty about the whole situation. His wife said he was so infuriated that he was threatening to get a lawyer involved. So I said I'd love to show the photos of their drain shooting water into my yard and all the clean-up we had to do as a result. After that I didn't hear much more except for a couple of nasty emails, which I ignored.

Finally the excavation of the walkout got done, not by Ken Brown, but by Michanie's people. As a commercial builder, they have all the equipment and people to do this sort of thing. Here's a picture of the excavator having dug out the area for the new retaining wall. They got right down the water table so in a couple of the low spots you could see water flowing. If you look closely, you can see an orange bucket behind the excavator, down in the mud, where I put the sump pump, and a hose for the pump going up out of the pit.

The base of the footings was supposed to be insulated, so there were a couple of layers of high density foam insulation that were put down first.  Then they installed the form-work for the footings.

A lot of rebar then got put into the space.  As I watched this thing take shape and compared it to the simple stacked-block retaining wall that used to be there, this all seemed a bit over-engineered. But I'm pretty sure that Michanie was doing all this concrete work for us for practically no profit margin on this part of the job. And that's probably because they originally proposed to build the retaining wall from blocks, but got push back from the architect and engineer who said it had to be poured concrete in order to satisfy the permit requirements.

The footings for the retaining wall were incredibly wide. Evidently this is because they need to hold back quite a bit of weight of the dirt behind them. In the picture below you can see just how wide the footings are, and the rebar where the wall itself will get poured.

After the footings were set up for a couple days the formwork for the walls went up. Again there was a lot of rebar that went into the walls. This is one solid walk out retaining wall.

The wall got poured, the top looked very smooth. When I saw the concrete work that was done by Michanie compared to the concrete work that had been done by Bramel, the difference was like night and day.  Michanie's work seemed to be very solid and precise. The texture of the finish was always very clean and smooth with Michanie.

After the retaining wall was set up for a couple of days they removed the form work, then came and patched up any small pockets and air bubbles by hand.

The outside of the retaining wall also got insulated, and then back-filled with sand.

The base of the walkout got a few inches of clear aggregate. This is the view we could see looking out of the back of our kitchen, for a while.

We were already living in the house by this time, and every morning at 7 or 7:30 we would see Sylvain and often another carpenter working at the back of the house. At this point the fencing was down and most of the construction debris clean up. We had sand and dirt for our front and back yard and these tractors were parked there for a few days.  It was really a good feeling to have the signs of activity and daily progress that were evident while Michanie was completing our renovation. The neighbors who used to hesitantly comment that things seemed to be taking a long time and that our first failed builder, Bramel, was almost never on site, now commented on how nice things were looking and how impressed they were with the professionalism and dedication of the workers.

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