Wednesday, August 26, 2009

293 Lyon Street Demo

In late May, the demolition of a rear shed at 293 Lyon Street revealed the neighbouring lot's peculiar shed featured in this URBSite post. 293 Lyon is the red-brick building behind the blue and white one at the corner of Lyon and Cooper:

Since then, this Sun story from June revealed that Carmen Argentina had bought 293 Lyon Street in April and plans to replace the oft-vandalized building with a multi-unit complex on the 31-by-99-foot lot. Photo #12 on this Ottawa Sun collection shows an additional interior view with the graffiti.

Because the house is in a zone with heritage designation (it's right at the border of the zone, according to eMAP), there must be a proposal to rebuild within five years before a demolition permit is issued. One assumes plans are ready, because a demolition permit was issued and will be carried out tomorrow.

This post contains a twice the usual number of photos because it combines shots from May and from earlier this week.

Here's the front of the house. In late May, previous graffiti had been recently cleared and the front door and window were boarded off. The window above the porch dormer was open. Since then, more graffiti was added. The plywood boarding up the front door has been removed, and yet another coat of graffiti is visible on the brickwork, as well as the front sidewalk and second-storey windows. A thin line across the middle of the facade suggests there was a full-length porch at some point many years in the past:

The front of the house has a bit of character to it. The roofline looks as though it were sliced off in a haphazard renovation some decades ago. (August photo)

Along the South side of the house, incomplete eavestroughing along the steep roof has led to damage to the brickwork. There's one window on the ground floor toward the rear of the building. (May photo)

The front porch is quite crooked, though the humble little porch light remains intact. (May photo)

On the North side of the house, along the laneway, there are two windows on each level. In May (first photo), the utilities were still connected, and the wall was relatively clean. You can see the yellow rear addition, and the gravel pad (at far right) where the previous shed had been. The shed featured in the URBSite post is visible on the other side of the fence. By this week (second photo), there is much more graffiti, and three sets of services are disconnected. The mesh cover over the basement window at the front of the house is also gone.

The two windows sticking out from the roof are undamaged by vandalism, though they've taken a beating from the elements.

At the rear of the house was an interesting extension. While the exterior wall is continuous, it's clear (especially post-demolition) that only half of it was built on a foundation. The demolition appears to have been done carefully, as some re-usable lumber is stacked up at the rear of the lot. While it was still standing, some Arabic girls drew flowers on the wall, and a dashed line with scissors around the rearmost doorway:

The rear of the roof back in May had a rope ladder slung over the chimney, probably by people breaking in through the (recent looking) rear window, whose screen is sliced and hanging down.

By August, the window has been removed (probably salvaged for future use), and surprisingly, the rope ladder has not.

Here's a view of the whole building from May, showing the relative proportions of the house and rear shed. The back wall has a cute little square window with a couple of panes broken.

Looking through the hole in the window, one could see the wooden dividing wall between the two sections of the rear part of the building (the sections with and without a foundation). The rearmost section was entirely uninsulated, full of litter and covered in graffiti. On the door dividing the section is written "Mort aux capitali$tes" ("death to capitalists")

In the corner between the back of the main part of the building and the rear extension were some bricks and a little shovel with a broken handle:

I was surprised to see the shovel still there after the rear part was removed. It was joined by a kitchen sink. I guess you can find anything at a demo site.

Here's the back of the building with its rear removed. You can see the foundation that was under part of the rear extension, and its interface with the main part of the building.

Looking closer at the side edge, you can get an idea of how the building was assembled, with a layer of brick exterior over a wood-board frame. At some point, a large opening was closed off and reduced to a single doorframe. The big gap in the crawlspace beneath probably made the whole house difficult to heat. And a couple of wires are still sticking out into the pit.

But they don't go anywhere. It's the end of the line for these wires--and for this house.

A couple of people I know who had looked at buying the house when it was on the market knew that it was a "fixer-upper" at least, and more likely a "tearer-downer." One person said it was only on the market for two days until it was picked up.

Let's hope the triplex that replaces it will fit in nicely with the heritage character of the neighbourhood.

Wednesday, August 19, 2009

Essence of a bagel

This past May, I was sitting on the ledge at Kettleman's Bagel Co. in the Glebe, waiting in line to order. From where I was sitting, you could see right to the back of the oven, and watch the fire burning inside.

If you ask me, this is the essence of the bagel.

[Look for more one-photo posts under the label Singles]

Sunday, August 16, 2009

150 Slater progress: Piles of fun III

In the previous post on 150 Slater's progress, I documented the construction of retaining walls around the former Rideau Winter Club building.

I also briefly mentioned a negative space becoming a positive one. Such a transition is even more pronounced on another part of the 150 Slater site, which will be the topic of today's post.

The Premier building, whose history and final days I documented in Down, Down, Down, Update 1, was separated from the building at 235 Laurier by a small alley. Looking at the building, you barely noticed it. Being a negative space, it was defined by the absence of anything between two very definable structures.

Let's get our bearings for a moment. In the image below, we see O'Connor Street in the foreground, with 235 Laurier squarely framed. You can see how some of the original siding was not replaced when the blue and glass cladding was added earlier this decade. In the foreground are some patches in the asphalt where holes had been dug to cut off services to the now-demolished buildings on the 150 Slater site.

Here's a closeup of the former siding. It's made from that ugly reinforced institutional glass with a grid of metal wires inside. The glass is filthy with years of dirt and grime. If this part of the wall is too far out of sight to re-clad, evidently it isn't worth cleaning, either. But having them here gives insight on how the new cladding relates to the old exterior: The new cladding essentially enshrouds these concrete fins, as it comes out further and has a lip below them. though I'm sure there was much work behind the glass as well.

At the back of the building, right below the old wall, are a pair of emergency exits, a gas connection and some ventilation panels. Since the building is still in use, the emergency exits must remain usable during the construction at 150 Slater. So a little structure was built to protect the accessway during the demolition of the Premier.

When the Premier's remains were extracted in mid-May and its site became an empty hole, the former alley became an enclosed passageway. In effect, negative and positive switched places.

By mid-June, the Premier's foundation walls had been demolished and the hole was filled in. Evidently, the demolition was very thorough, as a makeshift wooden walkway needed to be built to preserve access from the fire exit.

Under the boardwalk is revealed a gaping hole leftover from the foundation wall's demolition.

And in early July, piles had been driven and a retaining wall was built (as documented in the previous two posts on 150 Slater).

The gap under the walkway is still there, but the walkway is better supported now on the piles. You can also see a yellow hose--the gas line that comes from under the street to the back of the building. A worker is measuring the distance for the final segment of four-by-eights.

The machine used to install the tiebacks set me on a bent to learn more about construction of retaining walls. It's a very curious looking machine, which looks to me like the Predator alien from various films I haven't seen. It's rather photogenic, too, since its 'head' is suspended in the air at an angle.

Zooming in on the photo, I see the brand name Interoc, which suggests it may be an Interoc AN 140 Multi-purpose hydraulic drill rig. I believe this is the manufacturer's writeup. It's used to intall tiebacks, which is one fo the three primary ways of supporting retaining walls in construction sites, as illustrated in this diagram.

This particular rig, which is identified as unit number 05-28 in large black lettering on the back, is now being used at the construction site for 120 University, just over the Rideau Canal. A photo I have of the rig there has clearly written in the back, identifying the owner as Forages M.S.E. Drilling, Inc. of Ste-Martine, Quebec.

The previously-linked California PDF manual on foundations (28MB) has a good writeup on tiebacks beginning on page 11-1 (page 193 of the PDF), and a useful cross-section diagram on the following page.

In short, a cavity is drilled at the end of an angled hole behind the wall, and a steel wire is anchored into the cavity with concrete (the weight and firmness of the soil keeps it in place). A stretch of wire between the anchor and the wall, surrounded loosely by a shroud, can be tensioned to put pressure on the wall, holding it in place. Once tightened, a cap is placed on the wire to hold its position, and your wall is retained.

And that's it for the progress updates on 150 Slater. Let me show you the exit:

For all photos of 150 Slater's development, see previous posts marked with the "150 Slater" label.

Saturday, August 15, 2009

TD Bank throwback

Back in June, MM and I were standing on Elgin Street at Somerset, remarking at the 100-year-old sidewalk.

We were looking across the street at the current TD Canada Trust bank branch and noticing that it, too, has signs of where its exterior deposit slot had been replaced and painted over on the South end of the Elgin street wall.

I stood there contemplating how best to capture this in an image, when serendipity strikes and I get one chance to capture it as this old convertible drives through the frame:

Mission accomplished!

[I'll be posting more of these one-photo posts. Look for them under the label Singles]

Wednesday, August 12, 2009

150 Slater progress: Piles of fun II

It was sheer coincidence that I got this photo at the time I did. The angle of the crane's arm perfectly matches the angle of the shadow on the side wall of 235 Laurier at O'Connor. I had been tipped off that mid-June morning that they were removing the floor of the Rideau Winter Club.

The crane was supporting a green rig, which is a vibratory driver/extractor, according to this California PDF manual on foundations (28MB), specifically pages 7-21 to 7-23.

After piles were installed and the dirt removed from between the piles and the neighbouring building's garage structure, excavation could begin on the site. In this shot, taken the same day as the tip I mentioned in the first photo, they're about halfway through extracting the soil under the former Rideau Winter Club. You can see the former cooling tubes that are still present, nearly a century after first installed, and decades after they were last used.

In this photo sent to me earlier the same morning, you can get a better idea of the layering. Above the pipes was concrete, wood, reinforced concrete and/or fill, then the asphalt of the parking surface we'd known for many years. Beneath the pipes is soil infill, likely added when the rear of the building was decommissioned. Also note the hefty foundation walls on the far side.

Here's another one of those giant concrete foundation blocks, reminiscent almost of Stonehenge. It's hard to get scale, but judging by those stacks of what I suspect are four-by-eights, it's at least a couple feet thick.

By the end of June, digging out was mostly finished. these large white blocks have been installed along the top edge of the neigbouring building's underground garage, behind the piles for 150 Slater's retaining wall.

In early July, they were removing the soil from the lower level. Presumably they had run out of room to dig away from above. Behind this digger, you can see the retaining wall had been built up more. There's also a hole in the neighbouring parking garage. Maybe that was an "oops".

Here's a similar shot showing just the wall. I really like the layers in this shot. The white blocks are acting as the footing for a wooden barrier wall. Little triangles have been installed on the piles for the installation of tiebacks (incidentally, that's the page where I found the link to the Foundation manual. A good illustration of tiebacks is on page 194 of the PDF). I guess the neighbouring garage only goes down a storey or two, otherwise there wouldn't be any space for the tiebacks.

As I was going through my old photos, I found this one I took during this year's St. Patrick's Day parade. I had never before noticed that space between the two buildings, looking all the way to the World Exchange Centre, with its rooftop ball clock. Instinctively I took this photo. At the time, I had been oblivious that the Laurier Computer building (partial view on the left) was to be demolished. I guess my instincts were correct.

Lastly, here's a more square shot of the area from July 23rd. They've added a black tarp over the white blocks. They've also filled in behind the retaining wall (whose tiebacks have now been installed), and it has become a little catwalk, the negative space becoming a positive one. The spray-painted "EXIT" sign and the ladder gives it a Donkey Kong feel.

For all photos of 150 Slater's development, see previous posts marked with the "150 Slater" label.

Saturday, August 8, 2009

150 Slater progress: Piles of fun I

It's time for some updates on the construction at 150 Slater. In previous posts with the 150 Slater label, I documented the demolition of the buildings which used to occupy what is now the 150 Slater site. In the current trio of posts, I'm documenting the installation of the retaining walls, and the removal of the fill.

For reference, here's the site, taken kitty-corner from the intersection of Slater Street and O'Connor Street in Ottawa's Cetnral Business District:

Back in May, before the wooden barriers had been set up, they started driving piles for the retaining walls. Wikipedia has a good graphic here depicting different types of retaining walls.

In the North-East part of the site (the leftmost corner in the above photo, in front of the building), they drew circles with spray-paint using an upended garbage bin for the circle, and a string for a guide:

Into these circles were pounded giant steel cylinders.

Here are some of those cylinders outside the ground, with the machine used to install them behind. The cyclinders are making googly eyes at us:

They installed them outside the former foundations of the Rideau Winter Club (more recently known as Laurier Computer), which I documented in detail in this post. You can still see the little stairs leading up the side. After driving down the cylinders, fill was added, presumably to add support.

Here's another view of that machine. The working end is covered in a tarp:

There are also I-beams on site waiting to be installed. In the foreground of this shot is an old I-beam from the former Rideau Winter Club, which had been levelled a few decades ago. The I-beams in the former building's east wall were left a few feet high to act as fenceposts.

Into the cylinders, I-beam piles were driven into the ground, and the cylinders were removed. Tieback anchors are drilled into the ground behind. (I cover both of these steps as they are performed on different parts of the site in the next two posts, respectively). Besserer Street residents know very well the importance of a well-built retaining wall. Now that the wall is built, work can begin on extracting the soil contained in the newly-formed box.

As fill removal progresses andthe hole becomes deeper, ramps must be fashioned out of the remaining fill, before it, too, is removed:

Once the topsoil is all gone and they hit rock bottom, it's time to blow this joint. As this sign warns: "CAUTION: CONTROLLED BLASTING AHEAD"

Once rock becomes rubble (with the help of explosives), it can be removed, too. In the photo below, we can see how deep the rock is, and how far below they've gone. We can also see the piles continuing below the rock surface. Since they're building a three-storey underground parking garage with 210 spaces, they'll need to blast down by a storey or so.

Stay tuned for the next two posts, including photos of the excavation of the Rideau Winter Club's former foundation.