As this was written, on Aug. 20, Hedge Hall was something to watch as a crane swung long steel beams across the blue sky toward the building.

There’s plenty of new steel in Hedge already, says project manager Paul Farnsworth, but the creation of the building’s framework will become more of a spectator sport as it increasingly happens outside the building’s shell. That will include the skeleton for the building’s addition, adjacent to Alumni Walk — and the foundation for that addition was completed this week.

Then comes the roof structure. But before the roof work can be done, how about a place for the workers to stand?

Hedge as we know it comprises an original 19th-century portion and a 20th-century addition (the part currently lacking a roof). The older part never had a finished third floor. So to work on the roof on that end, a floor is in order. The underlying structure has “all been beefed up and now they have to put the subfloor over it,” Farnsworth says. “Once that’s in, they can shore up the roof that’s there, and then put in the steel for all of the roof at the same time.”

The original plan for the roof was to strip it all off and rebuild it completely. But general contractor Wright-Ryan Construction decided that time could be saved by retaining the remaining roof a while longer while the structure is built underneath.

In an interesting angle to the steel discussion, Farnsworth notes that after the beams are set in place, the bolts fastening them still must be tightened to an appropriate, er, tightness. Or, in the words of people like Farnsworth, who actually know what they’re talking about, torqued.

You can use a torque wrench, which shows you how tightly a bolt is turned. But later, when it’s time to inspect the steelwork, going around with a torque wrench to check the tension on every bolt would drive you nuts.

So instead the bolts are manufactured with cleverly engineered little extensions on the end. When the bolt is tightened up to spec, Farnsworth says, “the end breaks off, by design. Then, when they’re inspecting it, they don’t have to go around with a torque wrench.” The inspectors just look for the broken-off ends.

Roger Williams Hall is next in line for interior steel. You can see the smallish square holes in the roof into which columns will be lowered. A little steelwork has been done at the Bill already — perhaps you have seen the beam, set into the east wall, that will support a lintel over a passage between the new and old parts of the building.

So, much more steel is on the way. But you don’t need Campus Construction Update to tell you — although we will anyway — that with this sort of work you always have to do something else before you can do what you set out to do.

In this case, if you are going to hang a lot of steel, you need space to store it. And the Hedge-Roger Bill worksite currently doesn’t have much space because there’s so much excavation going on — digging for utilities and for foundation access.

However, says Farnsworth, “we are wrapping up site excavation, which is good because it frees up a lot of real estate when all the other trades” — i.e., workers for the next phases of construction — “and their materials start showing up. We need a place to stockpile stuff.”

He adds that no additional excavations outside the fence are expected.

The steam line installation between Hedge and Ladd Library, which required a big long trench that closed off the service road behind Ladd, is nearly done. The trench around the foundation of Roger Bill will be filled in soon, covering up the attractive Orangesicle-colored damproofing.

And what’s left for the underground work — a little more steam work near the Bill, and chilled water lines between the Bill and Hedge — will be started next week.

“Chilled water” lines? Farnsworth explains that a big water chiller in Chase Hall feeds the air conditioning in Chase, Ladd and Carnegie Science. Installing new, more-efficient air handlers into Ladd last year gave the system extra capacity. So during the Hedge-Ladd steam pipe replacement, chilled water service was extended to Hedge, whence it will connect to Roger Bill.

“It’s an efficient way to do it because it’s one central plant,” says Farnsworth. “The new projects don’t have to pick up their own cooling equipment. And you don’t have to find a place outside each building for the heat rejection portion” — that is, A/C exhaust.

Finally, Farnsworth shares a revelation that he and some colleagues had the other day while standing in a future classroom on the first floor of Hedge, at the end next to Dana Chem. They realized that this classroom will be “unique on campus because it has windows on both sides,” he says. “We have corner classrooms, but we don’t have one that has opposite windows.”

Look one way and there’s the Historic Quad; look the other, and there’s Pettengill. “It’s going to be a cool and unique place.”

Read about a and the renovation of. And here are the plans for the renovations of Hedge and Roger Williams halls.

With two louvers in place on the new Commons’ ventilation monitor, the crane has gone back for the next load. (Doug Hubley/ÀÖ²¥´«Ã½ College)

In recent weeks we’ve learned what Dining Services director Christine Schwartz likes about the new dining Commons. Now it’s the turn of Paul Farnsworth, ÀÖ²¥´«Ã½’ project manager for the building.

A mechanical engineer, Farnsworth especially appreciates the ventilation scheme. There’s no building-wide air conditioning per se. Instead, it’s essentially a natural system, he explained: the high-peaked main dining hall and an adjacent airshaft will create a chimney effect to pull fresh air in through windows that can actually be opened — an unusual feature these days in large new buildings.

The rising air will exit through the ventilation monitor, that big box on the roof. The air handling isn’t entirely natural, as the monitor contains big exhaust fans that will give nature a boost on the warmest days. Also in the monitor is a clever device that can direct rising air either straight outside or, on cold days, back down into the building so its heat won’t be wasted.

A test burn in the brick oven in the new Commons. (Doug Hubley/ÀÖ²¥´«Ã½ College)

Farnsworth also appreciates the sheer volume of the new Commons, especially that soaring dining hall and the 3,200-square-foot mezzanine that overlooks it. The building, he laughed, is “anticlaustrophobic.”

Finally, he said, “the level of finishes is special.” He pointed to the dark-gray granite that lines the main stairway and covers other walls, and to the pale maple wood throughout the interior, appearing as a veneer on the walls and as trim around doorways and on handrails.

In the realm of special finishes, we add another nominee: the tiles in the servery area. These include expanses of gleaming white wall tile and clusters of smaller glass squares in vivid splashes of mixed color.

The servery, in fact, is as much of a feast for the eyes as its cuisine will be for the palate. Snazzy ceiling fixtures, shiny stainless steel and abundant glass provide a lively play of light. Even the shapes of the food stations are attractive, especially the circular brick oven.

Sleek lighting fixtures in the new Commons. (Doug Hubley/ÀÖ²¥´«Ã½ College)

The serving stations are close to complete, with the millwork — cabinets, counters, knee walls, etc. — expected to be done this week. The pressure now is on the kitchen equipment installer, who is placing and connecting the myriad grills, broilers, ovens, burners, chillers and other gadgets that turn groceries into food.

Like much that happens in the construction biz, Farnsworth explained, that work rarely offers the gratification of orderly and straightforward progress. It’s not a march, it’s a dance: There are test-fittings, adjustments and delays if another trade needs to get at a location.

For example, Farnsworth pointed to a chrome pipe that supports a glass sneeze guard at the brick oven. The pipe attaches to a piece of wood inside a counter, close to an electrical junction box. So attaching that one piece involves the kitchen-equipment technician, carpenters and perhaps an electrician if the junction box is in the wrong place.

Meanwhile, the second story of the new dining Commons is essentially finished, aside from a lot of cleaning. The last big chore upstairs, Farnsworth reported, was the laying of carpet during the weekend of Jan. 12.

The brick oven station in the new Commons. (Doug Hubley/ÀÖ²¥´«Ã½ College)

He noted that weekend work for the carpet installers, or any of the trades, is nothing unusual. Workers have been on the job six days a week since ground was broken in autumn 2006. The project has been on the fast track since it began, and a six-day work week also affords logistical flexibility. For instance, because covering a floor pretty much precludes any other work in a given space, the carpet crew has often gone in on Saturdays, when there are fewer other trades to conflict with.

That carpet, meanwhile, has a dynamic rectilinear pattern in dark-chocolate brown and a pale tan that echoes the ubiquitous maple. The same material will appear throughout the building, and in fact the carpet people were prepping the main dining hall when Campus Construction Update passed through on Jan. 18.

With that 5,900-square-foot floor cordoned off, bare of workers and equipment, it was the first time we were really able to grasp the luxury of space that diners will enjoy in the new Commons. Anticlaustrophobic indeed.

New Commons’ west entrance. (Doug Hubley/ÀÖ²¥´«Ã½ College)

Another great leap forward in the second story was the removal of staging in the air-and-light shaft that reaches up to the ventilation monitor. That happened after workers hung the light fixtures and repainted the walls in a shade of green less violent than the previous choice.

Speaking of that monitor — and it may be the last time we do in this space — louvers were installed on its exterior during the second week of January. Also in the heavens, Farnsworth reported, roofers took advantage of warm weather that week to work on flashing and other finishing touches on the slate roof. And with the hanging of the main doors earlier in the month, major exterior work on the new Commons is done.

That same week, landscapers spread smooth blue-gray stones in the viewing garden next to the south-facing dining hall windows.

A view of the new Commons through Alumni Walk birches on a January day. (Doug Hubley/ÀÖ²¥´«Ã½ College)

Finally, Farnsworth expects to pass another milestone on Jan. 23, when the city of Lewiston issues a certificate of occupancy. This culminates a series of safety-related inspections covering everything from the elevator to fire alarms to emergency egress issues.

The Den: We received additional information about plans for the Den when Memorial Commons goes dark in less than a month. The Den’s new hours will be 8 a.m. to 2 p.m., and it will be closed in the summer.

280 College Street at dusk. (Phyllis Graber Jensen/ÀÖ²¥´«Ã½ College)

More imminently, Dining Services director Christine Schwartz announced that with old Commons closing, the Den will be used only for student dining during most of the winter recess, from Feb. 16 through 21. It’s expected that the new dining hall will serve its first meal to students Feb. 24, with a soft opening — aka “burn and learn,” in Schwartz’s words — during the days just prior.

Notes from underground: We haven’t talked about the steam heating system for a while, but one last chore was recently checked off that list. Now complete, the replacement of a connection between the steam plant and Merrill Gym was stalled some weeks ago when it was discovered that the existing steam lines were inaccessibly located beneath telecom conduits encased in concrete. Because the gym has its own boilers, it wasn’t a pressing task.

“It was easier just to find a different path for the steam, but that took several rounds of engineering because we didn’t want to reorder the piping,” which is custom-made, Farnsworth said. “We found a way around.”

Eventually those old telecom lines won’t be needed, Farnsworth noted. But they won’t be wasted. In 20 or 50 years their rediscovery will give Campus Construction Update fodder for a column.

Can we talk? What do you think about the campus improvements process? What would you like to know about it? What do you know that we don’t? We want to hear from you. Please e-mail your questions and comments to Doug Hubley, with “Construction Update” in the subject line.

Stones carpet the new viewing garden outside Commons. (Doug Hubley/ÀÖ²¥´«Ã½ College)