When you sign on the dotted line and purchase a new condo home, just about the biggest question you have is whether or not the suite will be ready any time close to the date the developer has given you. It can take a while for a developer to sell the required number of suites before a bank will finance construction of the project, and early purchasers have on occasion been left hanging for a few years.

…and then there are a couple of developers in the city who don't have to wait for bank financing to go ahead: these companies have built up the necessary experience, reputation, and funds over the years to go ahead on their own, and it means that purchasers have a far better idea of when their suite will be ready, as the building is already under construction. That's the case here on Bloor across from High Park. The developer is The Daniels Corporation, and even though sales have not started yet, work is in full swing on the Diamond Schmitt Architects-designed HighPark Condominiums.

HighPark Condominiums, by Diamond Schmitt Architects for The Daniels Corporation

There was a bit of a surprise waiting me when I arrived at the site, and it may be a bit of a revelation for others too. Why? We normally see a little bit of dirt and a whole lot of rock when we arrive at an excavation: at most Toronto construction sites you will find the underlying 'Dundas' shale below a few metres of top soil and mixed gravel. Here, however, it's all sand. That's right, the High Park area's hills, it turns out, are giant sand dunes.

Drilling rigs and a cement mixer finish work on piles for the sites' shoring, image by Craig White

Looking southeast across the sandy site, image by Craig White

Some people will be surprised to hear that you can build a 14-storey building atop sand, but you can, and in fact it's no problem: the taller towers to the north of HighPark Condominiums have been standing for 40 years in the same substrate, and in fact this part of the Bloor-Danforth subway line runs through it too. It does mean that you have to build a little differently of course, and as we can see in these photos, this is how you start an excavation in sand.

Below you'll see the tops of soldier piles—those are the vertical steel I-beams sticking out of the earth—and the lagging between them. Lagging is simply milled timber which holds back the earth behind them, with more slid into place as the excavation pit deepens.

Piles and lagging line the north edge of the excavation, image by Craig White

A shovel takes a scoop out of the ground, image by Craig White

Trucks are poised to haul excavated material away, image by Craig White

Below, the metal straps on the latest delivery of lagging are snapped. Workers here await the material needed to finish this piece of wall before moving on to shore up with next pieces pictured below that.

A worker snaps the straps of the latest lagging to arrive, image by Craig White

Piles await lagging: one metre of topsoil shows behind them, image by Craig White

At an even earlier stage of construction below, here the future lagging wall appears only as a few I-beams sticking out of the earth. These are all placed into precisely placed holes which have first been drilled to a depth greater than the final depth of the pit. Circular metal liners hold open the drill hole, and then concrete is poured into the completed hole. Next, the I-beam is inserted, held firmly once the concrete has cured.

Piles have been buried in the earth here, image by Craig White

At the back of the line, a drill pulls out more earth from a deepening hole. Just spin to release the excavated material!

A drill pulls out earth, image by Craig White

A quick spin, and the drill is ready to go back for more, image by Craig White

These photos were taken the week before last, and the area around this wall will have been excavated by now, and the first level of lagging installed here now too. 

So, that's how an excavation in sand looks as it starts. Want to know more that's coming here? Check out the dataBase page linked below. Want to comment? Add your voice to the conversation in one of the associated Forum threads, or leave a comment in the space provided on this page.

Related Companies:  Diamond Schmitt Architects, Isotherm Engineering Ltd., Land Art Design, Public Studio, tcgpr (The Communications Group), The Daniels Corporation, Tomas Pearce Interior Design Consulting Inc