Special feature: a barn door for the OKC container home

One special feature of the OKC container home that I wanted from the beginning was a barn door-type mechanism that could cover the sliding patio doors. I forget where the original inspiration came from, but minimizing waste and maximizing sustainability probably played large roles.

Because the patio doors required a very large rough opening, I wanted to use the panel Cisco would remove for it in some way. Removing big panel = big waste, potentially, but if I could devise a use for that material, then we could save some waste in the process. The creation of a barn door seemed to make a lot of sense.

First, the barn door would help regulate climate control on the container’s interior. It would essential be like a big metal blind, capable of either blocking sunlight completely or being rolled back to let the sun shine in. Second, I was working in the oil fields at the time, and that job requires me to be away from home for weeks at a time. Having a barn door that could lock from the inside would help secure the patio doors from potential break in. Last, the barn door would also protect the glass in the patio doors from flying debris in the event of a tornado or other severe storm.

Plus, it just looks cool!

barn door
This is the barn door fully opened, as it appeared following completion at Cisco’s shop in Tulsa.

barn door
Here it is partially open.

barn door closed
Here is the barn door fully closed, as it appears from the exterior.

barn door from interior
Here is a view from the interior, barn door fully closed.
Despite weighing several hundred pounds, the door slides easily and can be manipulated with one finger. This is thanks to the industrial-grade hardware we chose for the track mechanism. Although the space between the inside of the barn door and the outside of the patio door was calculated to an exact tolerance in Cisco’s controlled shop environment, the door has a tendency to bang a bit as it hangs, depending on the strength of the wind on site. Cisco was able to minimize this, however, with the addition of a clasp at the back of the door’s opening path.

clasp for barn door
A simple clasp helps minimize the wind from banging the barn door against the container as it dangles from its track.

Framing and floors for the OKC container home

By this point (late 2014), I had windows and doors picked out, and I had a steel cube in which to put them. The next step was having openings cut to accommodate the various sizes of the windows and doors. They call these “rough openings”. Once the rough openings were cut, a crew at Cisco in Tulsa would fabricate and weld metal frames inside the rough openings, then install the corresponding doors and windows.

rough outs and framing
Here you can see frameworks welded into the rough openings for the kitchen window and patio doors. The steel frames that line the rough openings would eventually be painted to match the container.
In addition to THAT framing work, I was also having Cisco’s crew install a kind of skeletal frame inside the container. This framework is not so much for structural support, as is the case on a wooden-framed house with 2×4 studs, but rather as a surface framework by which the infrastructure of the house (pipes, wires and insulation) could be installed and hidden by the hanging of drywall later on.

interior framing
Here you can see the aluminum studs that form a skeletal system for hiding the container’s infrastructure and attaching drywall.
We chose aluminum studs for the framework, with the logic that since the bulk of the container was naturally metal, it would make sense to continue using metal-based materials throughout. The use of aluminum studs would also cut down on potential future issues with moisture, mold, termites, rot and warping.

Following the installation of the internal framework, I went ahead and OK’d the finishing of the floor. My approach to this project from the get-go has been to retain the industrial look and “feel” of the container as much as possible. Retaining those aspects was not just an aesthetic goal, but also a practical objective in line with using fewer materials and reducing construction waste.

floor-before
BEFORE: The natural floor of the container, as seen after installation of the windows and doors and completion of the framing work.

floor-after
AFTER: The floor as seen after sanding and sealing with epoxy.
To use the natural floors of the container, Cisco would sand them down with a floor sander and then coat them with an epoxy sealant. Container floors are treated with chemicals that guard against insect infestation. These pesticides can be potentially dangerous through a process called “off gassing,” in which pesticide fumes gradually pollute the container atmosphere over time. By sanding off the container floor’s topical layer, we removed the outer most later of pesticide protection. The application of epoxy then sealed in any residual chemicals and prevents the floor from off gassing. It’s a process that works well enough for Cisco to use containers with original floors as offices within his warehouse.

Cisco's Office
A container inside Cisco’s warehouse in Tulsa has been converted into an office.

Selecting the box for the OKC container home

(NOTE: In my eagerness to bring you up to speed with my current construction progress, I forgot to mention the impetus and logic behind choosing the container that I have chosen for this project. In the interest of providing a complete recap, I present this entry retroactively.)

As the name of this blog and company implies, I’m constructing my container home out of a high-cube shipping container. While the box still retains a 40-foot length and eight-foot width common to most shipping containers, “high cube” refers to an exterior height of 9′ 6″ and an interior height of 8′ 6″. Standard containers are a foot shorter inside and out. I chose a high-cube box to maximize the internal volume and create a sense of airiness that would likely be missing with a shorter cube.

In addition to the dimensions of the cube, its condition was also a major consideration. Although there are claims of building homes from containers that cost only $2,000 or so, they’re typically unsuitable for a serious construction venture. They may work for someone’s utilitarian cabin in the woods, but I’m trying to build a showpiece prototype that will wow future clients. Michael Cisco, my fabrication guru at Tulsa’s Cisco Containers, suggested I use a one-trip container.

One-trip containers are manufactured overseas (typically in China), loaded with goods, shipped to their destination, emptied, and then put on the secondary market. It’s too costly to ship an empty container back to China, and America’s status as a global consumer prevents us from filling a container with goods and shipping it back. So, the container enters a secondary market, in which it may be purchased by a stateside shipping company for further use as a cargo carrier or for a different purpose, i.e. construction.

The image at the top of this post is what the inside of the raw one-trip, high-cube container looked like upon arrival at Cisco’s shop. The image below gives you an idea of the exterior.

The exterior of my 40-foot high cube container as it appeared upon arrival Nov. 14, 2014, at Cisco's shop in Tulsa.
The exterior of my 40-foot high cube container as it appeared upon arrival Nov. 14, 2014, at Cisco’s shop in Tulsa.

Windows and doors for the OKC container home

Author’s note: Edited 8/10/15 to update window and patio door glazing as WITHIN 2014 Energy Star performance standards.

From the outset, developing a strong thermal envelope was foremost in my mind. In addition to increasing energy efficiency with regard to climate control, a strong thermal envelope will increase my chances of having the container home Energy Star certified. Such certification then leads to the potential for thousands in tax credits, and I believe it would bolster my credibility as a green builder from a marketing standpoint.

Besides insulation, windows and doors are the primary saviors of thermal efficiency within a home.  They’re so crucial to the performance of the thermal envelope that Energy Star has a special criteria just for them. When you buy an old home (a fixer-upper), you’re buying all the old windows and doors, too (unless they’ve been replaced, of course, but in my limited experience I find this rare). So a 40- or even 60-year-old house may have doors built with 40- and 60-year-old technologies and considerations. Add to that the shifting sands of time wearing on the foundation, and eventually the cracks literally begin to show around windows and doors in the form of lost heating, cooling, and the money that purchases each. In fact, “A typical home contains a half-mile of cracks and gaps behind walls and around windows and doors, along with dozens of holes for pipes, vents, ducts, lighting, and wiring.

windows and doors
The container home as displayed during the fabrication process at Cisco Containers in Tulsa.

These windows are cookin’ with gas

With the plans mostly finalized, it was time to actually select the windows and doors that would transform the container (at least visually) from a big metal box into a tiny metal house. My architect contacted Womble Company in OKC, and Greg took our order from there. Womble deals in Pella windows, and the models we chose for the kitchen, bath and bedroom windows all contain “Advanced Low-E Insulating Glass.”

“Low-E” refers to “low emissivity,” which means a coating has been added to the glass during manufacture that makes it better at distributing and absorbing heat and cold than an untreated window. The effectiveness of the coating is measured by what’s called a U-factor or U-value; values closer to 1.0 are inefficient, while values closer to zero are more efficient. For example, untreated glass has a U-factor of 0.84, but my kitchen, bath and bedroom windows have U-factors at or below 0.25 0.29, which is JUST within the 2014 Energy Star minimum of 0.30 for this geographic region. (Because the windows were purchased in 2014, they are beholden to the 2014 standard). You can learn more about emissivity here.

Most low-e glazing furthers efficiency with the use of argon or krypton gas filling the internal gap (or gaps, if triple glazed) between the panes. Mine have argon filling their gaps. Krypton is more expensive, but, according to Green Building Advisor, “Don’t be tempted to buy glazing without argon or krypton gas … In almost any location in the U.S., argon gas and low-e coatings will quickly yield energy savings exceeding their cost.”

A final set of three windows will be added to the natural opening of the container, but I’m waiting until being closer to completion to do that, the idea being that I may need to move large objects in or out of the cargo doors. The cargo doors, by the way, will remain functional once the windows are installed in that opening, as I wanted to retain the option to shut the doors and lock them in case of severe weather, extended absence or zombie apocalypse.

The Doors

The sliding-glass patio doors are 0.32 u-factor, which is also within the 2014 Energy Star range. I also have a barn door-type panel that I can close to reduce sunlight exposure on the patio doors.

barn door open
With the barn door open, the patio doors can receive sunlight and airflow.
barn door closed
With the barn door closed, the patio doors are completely blocked from sunlight and other weather. The barn door also features a deadbolt that can only be accessed from inside, and, if necessary, padlocked as well.

Otherwise, the doors of the container home are metal security doors from Tell. We decided to go with their Spartan series of doors for the main entry and bedroom openings. The handles for the doors are from the Cortland series in satin chrome, and the deadbolts are single cylinders in satin nickel. Both are currently primer gray, but I will likely paint them once construction has finished.