2020 20K Home

Saturated Survey

The same week we passed stress test and received formal approval to build, we were able to complete our site survey. The good news is our site is relatively flat and surrounded by a seasonal creek on two sides; the bad news is the area most appropriate to build was also quite saturated.  Weeks prior, Newbern experienced unprecedented amounts of rain which was unfortunate for other projects but allowed us to experience our site in a worse case scenario for water permeability. 

Steve helped us negotiate the area to survey along with teaching us how to properly handle the transit and adjust stakes to find square.  We then plotted the data and began laying out our home on the site.  A key factor in our design is the “L” shape porch which allows for optimal sun exposure for passive heating/cooling and outdoor connection. 

Up until now we have been designing without a site, so our plan will need to be flipped, with the expansion porch facing south and the long front porch facing west, looking towards the neighbors pastoral property and sunset. 

Stressed and Tested

February was crunch time for the design process as we geared up for our “Stress Test” presentation. We began to refine our façade concept, material choices, and detailing. Always balancing the initial condition of the home with the potential for expansion and adaptation over time.

rendered elevations, sectional perspective, and exterior view showing proposed materials

Our presentation prompted a lively discussion about the decision-making process for design. The critics urged us to continue to push our expandability concept by detailing the house to allow for the owners to easily modify in the future. We discussed how to design these details both to facilitate future construction processes and to provide clues to the owner about how to expand.

exploded axon showing sequencing

After a long day of presentations, we all gathered to hear the verdict… and we were given the green light! We were urged to consider the 1,000 foot view of the 20K and to keep in mind that our home is one point within the context of the larger research project.

The next day we were introduced to our site and our clients! (Margie and Andrew). We are beyond excited to get to know the clients and to begin surveying and preparing the site for construction.

Devin exploring the site

Pole Barn Research and Review

Hello from the 2020 20K Team!

Based on our design development thus far, we have decided to incorporate a pole barn structure into our 20K Home design this year. In order to learn more about these type of structures and who is already building them in our community, we set off to do more research.

Typically, pole barns in this area are constructed using treated 6×6 wood posts and trusses composed of metal tubes, with either wood or metal purlins. We started talking with local contractors and manufacturers to get a better sense of pricing, construction options, details, and construction timeline.

After talking with Allen (one of the local pole barn contractors) he invited us to shadow him as he put up a 40′ x 120′ pole barn with his crew. On the first day the team installed all of the posts and cast the footings. We also helped them as they prepared for truss installation by establishing a datum to measure from.

On the second day: the team chopped the tops off the posts to level them, bolted the two halves of the truss together, and then raised them up atop the posts. It was helpful for us to observe the process and ask questions of the guys who do this every day. They’ve been an invaluable resource in helping us understand the possibilities and limitations of pole barn construction.

In conjunction with our research, we are continuing to design. We’re focusing on the “L” scheme with porches on two adjacent sides. We’re now diving further into the sectional implications of putting a small house under a big roof. We’re investigating different facade and insulation strategies and diving further into the details.

Devin & Charlie displaying their drawings and truss sample at last Friday’s review

Beginning Design

In considering the programmatic layout for the 2020 20K, we started by analyzing the programmatic layouts of the existing one-bedroom 20Ks and comparing their spatial organizations with our project goals. We liked the logical flow from public to private areas of the “Long Linear” schemes (such as Dave’s), however we felt that the narrow width limited the programmatic possibilities. In contrast, the “Horizontal Bar” schemes allowed for a longer front porch, increasing the area of this valuable outdoor living space. The “Squarish” plan is the most efficient; however, these homes feel smaller than the others when viewed from the outside because they lack a long façade.

In conjunction with our 20K analysis, we also selected a few precedence to study. The three that we settled on were: The Chamberlain Cottage by Marcel Breuer & Walter Gropius, The Sea Ranch Cottage by William Turnbull & Assoc, and Andrew’s Home (architect unknown).

After testing these programmatic layouts in plans of different dimensions, we arrived at a layout inspired by the Sea Ranch Cottage. This plan was not only the most efficient layout but it also provided for the most interior flexibility (allowing for an additional bedroom to be carved out of the living/dining room in the future).

Testing programmatic layouts and dimensions
Situating the plan within the pole barn

By using the post-frame construction method, we are able to build a larger roof and slab structure than previous 20Ks. Although we are still building a one-bedroom 20K, our plan is to situate the home within a larger structure that will allow for easy expansion in the future. Given the constraints of around a 500-600 square-foot home, situated within around a 1000 square-foot superstructure, we began to design the exterior space. From our visits to past 20Ks and other homes in the area, we set some parameters for the width of the exterior space (with a minimum of 6’ to allow for a comfortable sitting porch, and a maximum of 12’ to allow for light to penetrate into the home). With these parameters in mind, we looked at various ways in which our plan could fit within the larger superstructure, settling on two schemes to investigate further, what we call the “L” scheme and the “Front/Back” scheme.

Post-Frame Construction

Once we had a grasp on our priorities and goals for the 2020 20K project, we started to dig into the budget. We began by analyzing how much our target 20K client can afford. As we are aiming to make these homes available to someone living at the poverty line, we started with the US Census Bureau / American Community Survey statistics for poverty in Hale County in 2019. According to the ACS, an individual living in poverty in Hale County in 2019 makes around $12,500 per year, leaving them with a monthly income of $1,041. From this information, we determined that if the client is spending 25% of their monthly income on mortgage, they will be able to reserve $260 per month for mortgage payments. At a 5% interest rate for a 30-year mortgage, that gives us a price of $50,000.

Next, as point of comparison, we calculated how much the original three product-line homes (Dave’s, Mac’s, and Joanne’s) would cost if they were built today. We found that material costs have increased about 75% since 2009, so if the product line homes were built today, they would cost (in materials only) 21-26K. Since labor rates vary dramatically, we estimated that labor would average around the same as material costs, giving us a total cost of 42-52K for the product line homes in 2019. This puts the total cost of these homes right around our target cost of 50K, with no wiggle room for changes or upgrades.

From that point on, we started to research and consider alternative construction methods that could help us save on materials, labor, and time. In looking around the area, we noticed that many of the locally-built buildings in West Alabama use post-frame (or “pole-barn” construction methods). This type of construction uses large posts (or poles) on the eave ends of the building to carry the entire roof load – leaving the interior and the gable ends of the building free of load-bearing structural members.

Although this construction method is not typically used for residential structures, it can be, and in fact there are many advantages to doing so. The post-frame construction method involves first erecting the load-bearing posts, then installing the roof, and then infilling below the roof (versus traditional sequencing of stick-built construction starting with foundation, then walls, then roof). As compared with stick-built construction, post-frame construction can be faster, less expensive, and allow for more flexibility.  As a result of this investigation, we have decided to move forward with designing the 2020 20K using post-frame construction, which has never been tried before in any of the previous 23 iterations!