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Looking down the long deck of a historic cabin. The sun is lighting up the old stone wall and the large wooden pillars cast shadows on it.

Building Green, Custom Residential

Going the Extra Mile for an Unusual Addition

Living in a log cabin just might be one of the more sustainable things you can do. If you’re a city-dweller, you might never get the chance to do so unless you’re like one of our scrappy clients who saved a log cabin by attaching it to their home as an addition.

September 3, 2020

What is a sustainable home? What about a sustainable remodel? We've talked a lot about sustainability in our work. The built environment has such a massive impact on the carbon economy. Board & Vellum does a lot of residential projects and they usually fall into two categories: a new build or a remodel of an existing structure. But, there’s another option, too.

You could add an existing structure onto another existing structure instead of building a traditional addition. It sounds outrageous but bear with us. We’ll tell you about a project where we added a cabin onto an existing home but first, let’s talk sustainable building.

Building a new home makes sustainable design easy.

If we ignore the cost — both financial and the loss of the embodied carbon (the carbon used to produce what was already there) — it’s easy to make a new home very sustainable and high-performing. We have Certified Passive House Consultants (CPHCs) and LEED accredited team members who understand the science of how to make a great and sustainable project. While it’s exciting and amazing to work on such projects, the reality is working out the final solutions for sustainable new-builds is relatively easy.

Remodels make sustainable design a little harder.

A remodel is a whole different problem and one that, as a firm, we are passionate about. Remodels come with inherent restrictions. There are existing walls and built elements, lower budgets than you see with new-builds, and existing site conditions that can’t be changed. We can’t, for instance, re-orient a home towards the sun.

If done properly, a remodel is inherently sustainable because we’re keeping a lot of the embodied carbon — the existing wood framing has captured carbon in it and we don’t have to prepare as much new material as we would for a new building. When approaching a remodel, we look carefully at all the options available starting at our first pre-design meeting. From upgrades to insulation, the inclusion of high-performing mechanical systems, and even ways to capture and re-use rainwater, there are a lot of tools in our toolbox. Even if you can’t make an older home perform as well as a brand-new home, keeping most of it ends up being a fairly sustainable solution.

Sometimes, sustainable remodels mean going the extra mile.

Now let’s get back to that cabin-added-onto-a-house story. It started off as a normal, run of the mill remodel and addition — nothing too outrageous and relatively straight-forward. Then, the homeowners came across a historic log cabin slated to be torn down. Inspiration struck and we all thought maybe, as crazy as it might seem, they could add the log cabin onto their house as their addition. They could save an older structure, get a larger home to suit their needs, and reduce their footprint by keeping all of that embodied carbon. Not to mention the fact that they’d also end up with a freakin’ log cabin attached to their house. It was a win-win situation but we knew it would be a challenge.

The design, permitting, and construction processes seemed like one hurdle after another. Architects and designers are problem solvers by nature. We like weird problems and this was one of the weirder ones. Questions had to be explored and answered, solutions proposed and argued, and construction methods developed and implemented.

Our Pressing Questions

  • If the addition is an existing structure, how does the energy code apply? Remodels of existing structures only need to be brought up to the energy code as much as possible. But this was not only an addition but an existing building, just new to this site. Many discussions were had to make our case and work with the permit reviewers.
  • How and when do you move a house? Short answer, in the middle of the night. This explains why we don’t have a super cool video of the move, which still kills me.
  • How do you decide the best way to add on to the house existing house and ensure it works with both the existing structures? Lots of measuring, analysis of lot coverage and setbacks, and luck come together to ensure it all works.

It certainly wasn't the easiest solution, but sometimes something that takes more effort can create a project that is so much greater than the sum of the parts. This project saved a historic and loved structure, it created a story for the homeowner, it captured a lot of embodied carbon and energy, and it saved the cost of all new framing.


In the end, a project like this isn’t going to be all that common. With a team excited to jump into creative problem solving and dedicated to coming up with solutions, not just focus on the challenges, the end result is a sustainable solution to a really unique problem. It is also one heck of a log cabin.

Would you like to read more from the team?

If you enjoy reading our blog as much as we enjoy writing it, that just makes our day! You might also enjoy a few of the related posts below. And, if there is a topic that you wish we would cover, let us know!

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Considering a project? Or, just curious about something?

Send us your questions about design, architecture, interiors, landscape, LEGO rooms… Anything, really. We’re always eager to meet new people, and we’d love to get to know you, your project, and your goals.

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