OPEN_1 Blog

The OPEN_1 Blog is closed. We're starting fresh on the OPEN_2 project. This page has the archive of the OPEN_1 blog, so you can see what it was like.

We at Bensonwood thought it would be interesting to provide a blog on this website, written by those of us here who are directly involved in the OPEN Prototype project. This is a space for informal notes and musings about progress on the project, difficulties we encounter, successes we achieve, and anything else that seems interesting and relevant. Our goal is to have new entries at least once a week. We are open to our partners in the OPEN Prototype project--those from MIT and those from Crotched Mountain--contributing to this blog as well.

What's happening for me today with the OPEN Prototype? I updated the folks at Crotched Mountain on the date that we propose to start our "twenty day" push on site, and the news seems to have met with a mixed response. Scheduling is one of the most challenging tasks we project managers at Bensonwood face. I am confident that we and our client on this project will be able to work through the competing needs and desires to agree on an appropriate starting date.

The bigger challenge, certainly, will be coming as close as we can to meeting the project goal of "twenty working days on site." Several consultants to the project have already expressed (off the record!) their opinion that there is no way we will complete this home in twenty days on site--"two months" was their guess. Their skepticism is helping to fuel our efforts. We are not yet ready to throw in the towel on the ambitious schedule goal.

At the desk next to mine, Tony is busy orchestrating subcontractors and suppliers, and refining the various project schedules. Next door in the Building Systems office, Eli, Hans, and others are working furiously to crank out the shop drawings necessary for production. And in the Building Systems shop itself, the sprinkler piping and lights have been preinstalled in our floor systems, the boiler and water storage tank are mounted in the prefabricated mechanical room, and the mechanical core wall is beginning to take shape. Now if Scott Harrington (the plumber) would just get back from his vacation...

Update from the Bensonwood Shop

Since we're pushing ourselves with this project, we're also doing a lot of documentation. I've been photographing the in-shop fabrication for a couple of days now, and we've got a videographer in today to capture some of the assembly on film for us. I'm impressed with how quickly things are going together in the shop.

Mechanical Room

One of the things we're doing differently on OPEN_1 is constructing a basement-level mechanical room in our shop. The room will have the major plumbing and HVAC systems pre-installed, and will be shipped and installed as a single piece. We've shipped walls with wiring installed, but we've never shipped a room, especailly one with as much stuff as this...

Where's Eli?

We just survived a week without Eli Gould, the intrepid lead designer for the OPEN Prototype project. Eli's wife Jessica gave birth to a lovely baby girl last Friday, and as if that was not enough excitement, the family moved into a new house on Saturday. We wish Eli, Jessica, son Calvin and daughter Eva all the best.

Now about that Prototype. The lights and cameras that were here last week don't usually accompany the action at Bensonwood. However, in an effort to document the OPEN Prototype project, we have hired a videographer and a still photographer. Both of them kept the Prototype team hopping for a day last week. Initial reviews of the rough-cut video shots included the comments "educational," "wicked cool," and "the workers look uncomfortable." I don't think we will be nominated for any Oscars.

Today we firmed up the schedule for Bensonwood's work on site. We plan to begin assembling the shell of the Prototype on Monday, 19Jun06. We will work for ten days, and then take a one week break to allow for the July 4th holiday, mid-progress tours and documentation of the project, and exterior work such as landscaping and paving. We will pick up ourwork again on site on Monday, 10Jul06, and--with some luck--the Prototype will be complete ten days later.

Attic Raceway

In the shop this week, they're assembling the attic raceway. This whole unit will be pre-assembled, shipped to the site, and installed with one crane pick. It holds a lot of the larger HVAC units, as well as some plumbing and electrical units. Pictures of the shop work are after the jump...

"Build It Twice"--first virtually, then in the shop

The mood at our weekly team meeting yesterday was excitement mixed with nervousness. We are not yet in panic mode, but we are ratcheting up the intensity of a process that is already causing a couple of folks here to lose sleep. We don't worry so much about Eli lying awake at night thinking about this project, because we figure he is being regularly woken up by his three week old daughter anyway.

One goal of the OPEN Prototype is to solve construction problems virtually in a computer model before we build components in our shop or assemble them on site. Modeling these elements accurately by computer requires that we nail down a huge amount of information about the component, the materials and equipment that go into it, and the other components and systems with which it interacts. For example, for us accurately to draw the interior walls, we have to know where all of the electrical, data, plumbing and HVAC components will be located in those walls, what finishes will be applied to the walls at various locations, and how these walls will interface with floors, ceilings, timbers, built-ins, fixtures, and other walls.

The "typical" construction process would involve carpenters figuring out the wall intersections on site, subcontractors boring, notching, and entangling these walls on a "first come, first served" basis (pity the sub who works on the walls last!), and drywallers and finish carpenters trying to make the best of what they are left to work with. We are trying something different here, and realizing how important the flow of information "upstream" is to the success of our work--especially for a building as complicated as this first Open Prototye.

Visualizing Component Relationships

The other day on our shop floor I had an interesting conversation with Herb Hurlburt, the Master Electrician for the OPEN Prototype. Herb was working with three of his electricians to run wires in the attic system and the mechanical core wall that had been preassembled and pre-plumbed in our shop.

While Herb appreciated the access and control that working on these components in the shop provided, he also acknowledged that it could be challenging to understand how the various individual components related to each other, from the perspective of wiring. The core wall, for example, is assembled horizontally on the shop floor, but will be installed vertically in the building. Herb has to understand these relationships, because he has to figure out the circuiting as the wires are installed.

One challenge with the electrical system has been to obtain the information necessary to draw all of the fixtures and devices accurately on our plans. Another challenge has been to communicate this information in an efficient way to the people like Herb who are working on the shop floor. We have found innovative ways to convey the information. For example, Eli generated elevation drawings of each of the walls that need to be wired, and stapled these drawings to the walls in the proper orientation. These "visual aids" have been a big help to the electricians.

"Wiring a modular home is simpler," said Herb, "because in the factory they simply set the walls up in the same relationship that they will have in the finished home. Because here we are working with assemblies of components, the relationships are not as obvious. But we are figuring it out--and the next one will be a lot easier!"

Forces Beyond Our Control

One of the objectives of the OPEN Prototype is to demonstrate the speed and efficiency of construction that are possible on site when components are preassembled and prefinished in our shop. However, we are still going to have to deal with Mother Nature during our twenty days of work on site.

We were reminded of the unique challenges of Crotched Mountain's site the other day when Tony and Hans were installing 4x8 sheets of rigid foam to insulate the concrete slab. Tony reported that while carrying a sheet of the insulation, the wind whistling across the campus nearly blew him over. And we are planning to fly 30' long wall systems?!

I suspect that we will prefer strong winds to rain, however. We have scheduled a "kickoff" event for 10 a.m. on June 19, and we do not yet have a "Plan B" if it's raining that morning. The construction team is reserving the right to hold off on work for a day or two in the unlikely event that the weather is terrible during the first week of work on site. After that first week, the shell should be be fully dried-in, and we would not expect rain or wind to significantly hamper our progress.

Truck load

This is the attic raceway, complete and loaded on a truck bed. We didn't actually ship it when I took this picture; the raceway was wrapped in plastic and stored on the flatbed for a few weeks, because we needed the room in the shop.

At the moment, the shop is full to the brim with walls. They're getting wired, plumbed (when appropriate) drywalled, housewrapped, and windowed. Then they're getting bundled and wrapped for shipping.

In the Timberframe shop, a pre-assembled section of roof is currently getting wired. I'll put pictures of both up, as soon as I've processed them.

All Hands on Deck

One of Bensonwood's greatest strengths is the broad capability of the people who work here. This wide range of skills and a culture of mutual support are our best allies during times like this.

Because the craftspeople in our four different production shops (timberframe, building systems, roof panels, and woodworking) are multi-talented, during "crunch times" we can shift people to the areas most in need. We are now officially in "crunch time" for the OPEN Prototype, and the area most in need is our building systems shop. Folks from various parts of the company have responded to the call for assistance, and we now have a number of timberframers, the team from our roof panel shop, and even the occasional architect, engineer, and project steward working to frame and finish walls in the building systems shop.

There are benefits in addition to increased production that result when folks from different sectors of the company find themselves working side-by-side toward a common goal. The work is educational for those involved, and can be an invigorating change of pace from our more usual routines. The experience also cultivates teamwork, appreciation, and mutual respect across departmental lines.

Wall building in the Bensonwood shop

I've got three new pictures from the Bensonwood shop. Most of these are pictures of wall fabrication and pre-finishing.

In the Timberframe Shop

It is getting hard to take pictures in the building systems shop. There are so many walls being worked on that it is hard to get a clear picture of any details (or of what is going on).

So, to shift gears a bit, here's a picture from the timberframe shop, of the porch roof assembly...

A Lesson Learned

We are in the final push in our shops to prepare for the start of our work on site Monday morning. The shops are filled with wall panels, preassembled floor systems, and roof panels. We are installing siding on the exterior wall panels, and have fabricated the roof panels with a ventilation channel, for a "cold roof." Our timberframe shop has been relatively quiet this week, as framers are helping to finish building components for the prototype. The yard outside the shops is filled with wrapped bundles of panels ready for delivery to the site.

The other day I started a list of "Lessons Learned from OPEN_1." As this building is the first of a series, we expect that each subsequent prototype will be an improvement on the last one. One of the big lessons we have learned so far is that it would have been better to have worked out all of the design and construction detailing prior to starting fabrication of the building components. However, we live in a real world in which other projects, the schedules of subcontractors, and the availability of human resources have all significantly affected the OPEN Prototype process. We were able to predesign and pre-engineer the "big pieces," including a dizzying array of interelated mechanical, electrical, and plumbing components. These pieces have now all come together in our shops. However, we are having to work out some of the minor details as we go. Better to be working these details out in our shops, though, than in the chaos of the typical job site. Stay tuned to find out just how chaotic this job site turns out to be...

On-site: Day One

Despite the heat and humidity, and a big thunderstorm in the afternoon, things got off to a roaring start on the 19th. By the end of the day, the walkout basement walls were all in place, and about half of the joists for the first floor were in place.

Two Days Down (Eighteen to Go?)

After two days of work on site, I have a greater appreciation for the "prototype" aspects of this project. I am also reminded of how hard our crews work when on site.

We have already achieved some notable successes on site. The prefabricated mechanical room was the first module we flew into place on Monday morning, and a couple of hours later the electrical panel in that module was fully powered and supplying juice to our tools. On Tuesday, the electricians made the connections for a number of circuits in the ground floor, and informed us that we could use the preinstalled can lights if we wanted to work after dark. They did not have any takers yesterday. Scott Harrington, the plumber, hooked up the drain pipes that had been preinstalled in the mechanical core wall to the sub-slab drain lines. Thus far, the systems that these subs preinstalled in the wall and floor systems seem to be coming together as planned on site.

We have also been pleased to see that the finishes we pre-installed on the wall panels, such as exterior siding and pre-taped, pre-painted DensArmor wall board, survived the delivery trip and the crane picks in good shape.

On every project in which we push the envelope of prefabrication, we learn lessons about tolerances: where to leave room for adjustment, and where to go for snug fits. The MacMillin Company did a fine job on the foundation, but even so, marrying our shop-built panels to the site-placed concrete involved some adjustment. Due to considerations involving the mechanical systems, and a desire to experiment with a new floor system, part of the first floor system is supported by timber joists, and part by steel bar joists. The lessons we are learning about the relative merits of these systems, and how efficiently to join them, will serve us well the next time we try something similar.

The crew is generally in good spirits despite the unsettled weather, the heat, and the "no shorts" rule. I am heading out to the site this morning to do what I can to lend a hand.

One week on-site

Five of our twenty days on site are gone. Are we nervous? Maybe a little.

On the bright side, the enclosure is almost complete. The Benson crew is working on the sunroom today, which is the last of the walls to go in place. Once that is done, all the action moves to finishing. The exterior needs trimming out, the siding needs to be finished, and doors need to be installed (windows are already in place).

On the inside, both the plumber and electrician have had crews in place for the first week. When a wall is set in place, the electricians are right there, connecting the wires, and hooking everything to the box. The plumbers have been connecting the pre-plumbed walls. If all goes well, they should be done by the end of this week, leaving the interior to the finish carpenters, who will be installing interior doors, trim, and stairs. It has been a hard push by everyone, but, when talking with the crew this morning, they're all proud of what they've done, and confident that they'll meet the twenty business day deadline.

Measuring Success

Well, it's been a quiet week on the Benson Blogosphere.

Work on the OPEN Prototype continues at a steady pace. Tony and Eli have been on site nearly every working day since we kicked off the project. Tony spends much of his time coordinating the work of subcontractors representing over twenty different trades. Eli is the Answer Man when it comes to questions about how a particular intersection or detail is to be executed. Both are handling their site management roles with their tool bags on.

By the end of the first two weeks of work, we had made tremendous progress, but were not as far along as we thought we had to be in order to hit our self-imposed "twenty day" construction goal. The frequent heavy rains during the first two weeks slowed our progress, and fitting together the large pieces of this prototype puzzle ended up taking longer than we had expected.

Halfway through our projected schedule, we were faced with two choices: we could continue to work extreme hours under sometimes-questionable conditions in an effort to hit the twenty-day goal, or we could dial back the frenetic pace by a notch or two, and focus on delivering the highest quality end product, as efficiently and safely as possible. We opted for the latter strategy.

The ambitious goals we set for this project--in particular, the twenty-day construction schedule--have served to inspire and motivate the efforts of our team. The risk of setting such ambitious goals is that if we fall short on one of them, we may feel that we have failed, when in fact by any other measure, the project would be considered a success. We are on track to complete this complex prototype home in five to six weeks of work on site, rather than four. In my experience, that's a schedule worthy of celebration.

The Home Stretch

I just spent two days working on the OPEN Prototype site. Last week, Tony and Eli had determined that taping the sheetrock with three coats of joint compound was likely to be a limiting step on the critical path to completion. This week a carpenter and I joined the two professional tapers, and by yesterday, most of the sheetrock in the Prototype was ready for paint.

The painters have already finished the walls and ceilings on the ground floor, and most of the finished flooring has been laid there. The painting crew (which is also the flooring installation crew) will be working on the second floor today and tomorrow. This weekend, they will paint and lay flooring on the first floor. Throughout the building, the cabinets and counters are installed, the demountable ceiling panels are in place, many of the plumbing fixtures are installed, as are most of the lights, outlets, and switches. Our Woodworking Team is on site in full force today, installing wainscot and interior trim. We plan to test-fire the HVAC system on Monday.

One of our strategies to condense the schedule on site was to eliminate as many "wet" trades as possible--or to do as much of the "wet" work as possible in our shop. We pre-sheetrocked, taped, and even painted many of the walls while they were in our shop. We will also be using wood trim strips to cover joints at the intersections of some walls. However, a large number of sheetrock seams still had to be taped on site. These included joints between panels that are in plane with each other, intersections with timbers, and a number of walls that, due to their location or shape, had to be built on site. In future prototypes, we will look closely at how and where we are using sheetrock, in order to determine ways to further reduce the need for time-consuming finishing on site.

OPEN_1 is done

So, as Andrew said earler, we didn't finish in 20 days. Still, the OPEN_1 prototype is now complete. Some of Crotched Mountain's staff held a meeting in the building last week. A bunch of Bensonwood staff are going over today, for our regularly-scheduled company meeting. It will include a walkthrough of the building and a "what we've learned" discussion from some of the most involved associates. Even though we didn't finish in 20 days, the finished building is quite impressive and is a real testament to the commitment and skill of the people who worked on it.

I hope to get some photos of the finished building soon, although I'd prefer to wait until it is furnished an inhabited.

Lessons Learned on OPEN_1

Now that some time has passed since the completion of our first OPEN Prototype project, we have developed some perspective on the elements of this project that worked well, and those we would like to improve in subsequent prototype projects.

Perhaps the most important lesson was more of a reminder of something that we already knew, but that we were not able fully to implement on this project. We have been saying for years that a shop is the best place to build the components of a house, and the site is most appropriate to assemble them. Those parts of OPEN_1 that we were able to preassemble and prefinish in our shop worked well and saved time on site. However, time constraints kept us from completing some of the components in our shop as we had hoped. The work that this resulted in on site was very inefficient, with subcontractors trying to work on top of and around one another in a short space of time. A good example of this lack of efficiency was in the siding. Had we been able to preinstall all of the siding in our shop, as we had planned, then we would not have had carpenters on scaffolding in the rain installing some of the siding on site. The next time around, we plan to allow more time for finishing components in the shop, and we expect this to result in additional savings of time on site.

Assembling multiple large components on site helped us to understand the tolerances needed at the intersections between components. In some cases, we cut the dimensions too close, when in fact it would have been to leave more "play." For example, we prebuilt the interior partition walls for the basement to span the entire height between the floor slab and the ceiling. When we found that the slab was not as level as we had hoped, we had to plane the bottom plates of the walls. We ended up installing trim anyway at the tops of the walls where they meet the ceiling panels, and that trim could have picked up the necessary tolerance.

Another lesson that we already knew, but did not fully execute due to the tight schedule, is that whenever possible, we should work out all of the construction details virtually, in the 3-D computer model, before starting fabrication in our shop. Those elements for which we had detailed shop drawings went together quickly in the shop and smoothly on site. When we had to stop work to figure out a particular intersection or detail in the shop or on site, our efficiency plummeted. We will certainly want to allow more time for planning the next prototype project.

The input that we had from subcontractors during the planning process was invaluable for integrating the various systems within the home-particularly the plumbing, HVAC, and electrical systems. Even so, these subs were challenged to preinstall the pipes, ducts, and wires in our shop, because it was difficult to visualize the relationship of one component to the next. For example, we built the mechanical core wall horizontally on our shop floor, but in the house it runs vertically. We found that by creating shop drawings oriented the same way that the component was sitting in our shop, the subcontractors had an easier time with their installations.

We were reminded on this project of the value of making mock-ups to prototype new components and assemblies. The mock-up that our Building Systems and Woodworking teams made for the wainscot and the valance convectors helped us to refine the details, and also made it easier for our subs to understand these prototype components.

As Tedd Benson has said since we completed this project, "we had to prototype everything!" This statement leads to several other important lessons from this project. One is that as a company, we are capable of taking on extremely complex projects and executing them successfully in a very short time frame. Another lesson is that we don't necessarily want to repeat the size or complexity of this project in the next OPEN Prototype home ("OPEN_2").

Because of the nature of this project-a two-family home that would serve people recovering from brain injuries-a certain level of complexity was inevitable. The digital direct control (DDC) system that allows the entire house to be remotely monitored and controlled is one example of such complexity. The elevator is another. The person lifts, accessibility considerations, and HVAC requirements all contributed to making this project more "involved" than Tedd Benson and Kent Larson had originally envisioned it. When we wove these client-specific requests into our own goals for the project, the resulting tapestry was impressive and, at times, mind-boggling.

Because this project involved so much R&D on our part, and we tend to execute our R&D in our production line, the project had a significant effect on other, non-prototype projects that were also in our schedule. For OPEN_2, we will limit the number of R&D fronts on which we are operating, and also find ways to ensure that the R&D does not hinder the production of other projects.

This document has tended to focus on the areas in which we hope to improve our process for OPEN_2, because we are a company that is constantly on the quest for continuous improvement. However, the successes of this project far outweigh the modest failures, and in fact most of the failures appear so only with respect to the dramatically ambitious goals with which we began.

The list of successes is long, and includes:

We are looking forward to taking the successes and lessons of OPEN_1, and applying them to OPEN_2. We are tentatively planning to be on site with OPEN_2 in October of 2007. We will be releasing more information about this next project as we firm up the details.