healthy homes Archives - Living Craft

How to Build in the Face of Climate Change

Currently the conventional construction industry contributes heavily to climate change. That cannot be debated. What if it could be changed?

Welcome to the modern world of increasing carbon emissions.

No matter the exact numbers, we know that creating buildings from new materials that have been manufactured and then shipped long distances, using machinery that consumes fuel and electricity, and assembled by workers who travel to the site daily in gas burning vehicles cannot be the greatest thing for the planet right now. We are struggling with the real effects of climate change in the present day, while also hearing every day about the potential futures we and our children will face.

How can building actually help?

We are part of a small but growing class of builders who believe we can offer some solutions to the big problems of carbon emissions associated with construction. Some ways this can be done:

Use Local Materials

If you don’t have to ship pine boards from New Zealand, but can instead use wood harvested sustainably from the same region that you are building in, this will reduce the embodied energy of that material. Unless you live in New Zealand, and then go for it with your pine. If you live somewhere where forests aren’t abundant, then you could look into other options like straw bale, masonry, or stone.

Their local abundance is part of why we love to use natural plasters. Sand, clay, and lime are harvested and processed fairly locally, not shipped from across the sea. These materials can be used for floors, walls, and more.

Use Materials with Lower Embodied Energy

If you can choose build a home out of cement blocks or adobe blocks, you can drastically reduce your building’s carbon footprint by choosing the adobe. Cement is one of the biggest greenhouse gas emitters, but adobe blocks can provide as much structural support, increased thermal mass (means more comfortable home in the face of extreme temperature swings), and a much lower embodied energy.

Similarly to how single use to-go containers made of styrofoam can’t ever be considered “green,” a home insulated with lots of foam is also not very green, because of the amount of energy it requires to manufacture that foam. Materials like straw, hemp, and cellulose can perform just as well, at a lower embodied energy cost. There are many more examples of this, so feel free to ask us about low energy materials when designing your dream home!

Use Materials that Sequester Carbon

Straw is made of carbon, and when a home is insulated with carbon-rich materials like that, you’re locking that carbon out of the atmosphere for the life of the building, How cool is that?

In contrast, a fiberglass batt or mineral wool board (or foam of any kind) takes a ton of energy to create and doesn’t sequester carbon at all. Bummer.

Other materials that sequester carbon: wood studs, hemp, cross laminated timber, and fiber boards (some made from hemp are coming onto the market soon).

Practice Efficient Home Design

Paying attention to your climate and site conditions and using principles of passive solar design will keep your home comfortable throughout the seasons while reducing your energy bills. It also lowers your carbon emissions.

Another part of designing a wall system is preventing air and water leaks. A tightly air-sealed and well-insulated home will last longer, reduce issues of mold or rot, and be more energy efficient for both heating and cooling.

Start today

It’s a good start to begin thinking about some of the factors listed above when designing and building a home. We can’t change the industry overnight, but the broader acceptance of low carbon building methods today could go a long way.

7 Reasons to Keep Your Old Plaster or Plaster New Walls

You could say that lime plaster forms the foundation of our company, or at least of our origin story. The three of us met on a big lime plaster job in the mountains west of Boulder, CO. We each contacted our mentor, Ryan Chivers, because we had heard of his reputation in the natural building community as a lime plaster expert. Frank had worked with him for a year at that time, and this project was mine and Ben’s first time meeting Ryan. He brought us on to help him sling plaster on both the exterior and interior of this strawbale mountain home. And, as they say, the rest is history.

Here are a few of the reasons we love lime. Whether it’s found in a historic home where plaster was the primary choice for wall building at the time (lime or gypsum), or a new build or remodel where the homeowner chooses to use plaster, this material is definitely not out of style.

1. Beauty

Have you heard the word birefringence? I hadn’t either, until I met Frank. Wikipedia defines it as so: “Birefringence is the optical property of a material having a refractive index that depends on the polarization and propagation direction of light.” Well, maybe that cleared things up for some of us…

The point is, because lime plaster cures back to it’s original material of limestone, it maintains some of the aesthetically enchanting qualities and depth of a natural gemstone or mineral, while being customizable in texture and color.

2. Durability

We all know that something that’s rock solid is very dependable. So, if someone gave you the choice to have walls that are literally rock solid, wouldn’t you take them up on that? It sounds like a no brainer to me.

3. Easy to Repair

One miraculous feature of lime plaster is that it is actually constantly repairing itself on a microscopic level. When small cracks form, new lime is exposed to air and moisture, which causes a continuing reaction which can self-heal smaller cracks. In case your lime plastered walls do get some bigger cracks, or a couple scratches, or an historic wall system needs repair, lime plaster can be repaired by a skilled plasterer. There are even artisans replicating plaster relief art in historic renovation.

4. It’s got History

Today, I told a material supplier that the products I was picking up were going to be used on a exterior plaster job, using lime plaster. He looked surprised and said, “Now that’s old school.” And he is not wrong! But the best thing about an old school material like lime it that it’s tried and true. And lime has been used in building mortars and plasters since the Greek and Roman heydays.

5. Low Carbon Footprint

As lime cures, it actually absorbs CO2 from the atmosphere. While there is still energy input during the production and shipping of lime (we call this it’s embodied energy), the curing process helps to offset this carbon footprint. Plus, lime is a more local product in many locations, particularly here in the Denver area, which means less fuel is burned for transportation than a cement stucco or paint.

6. Support your Local Craftsmen and Craftswomen

Many trade groups and magazines are extolling the virtues of skilled craftspeople in construction. The hashtag #keepcraftalive is one example I saw recently. Like many trades in the building industry, the workforce of skilled plasterers is diminishing. Hiring a local plaster company is one way to help rekindle the movement of skilled laborers coming up in the workforce. Plus, dollars spent on local products and with small businesses are more likely to stay in the community.

7. Improve Indoor Air Quality

Plaster improves indoor air quality in a few ways. One is that lime plaster contains no chemicals that can off-gas into the indoor atmosphere. Those are things like VOCs (found in some paints and stains). Instead, plaster is made of solely natural materials like sand and lime, with nothing that will emit noxious chemicals into the home.

Another way plasters improve air quality is managing humidity levels. We wrote a full blog on plaster and humidity over at our plaster specific website, Living Plasters. The general idea is that whether humidity is too low or too high, it can be bad for indoor air quality, or make your home feel uncomfortable. Plasters act as a buffer to moderate humidity levels in the “Goldilocks Zone” of just-right.

Personally, I’m excited to be part of reviving the lime plaster movement and beautifying our homes and buildings.

Case Study: A Straw-Cell Addition

Living Craft Design has been working on a straw bale addition to our friends’ home in Boulder. This family is already well-versed in the benefits of natural building, so their addition incorporates passive solar heating with large, south-facing windows and a concrete slab floor to hold all that sun-generated heat. The addition has the high insulation value (R-value) that is a great feature of straw bales as a building material. Additionally, the family chose to renovate the original rooms of their home and filled the walls and ceilings with densely-packed blown cellulose as part of that process. This home will be comfortable year-round and have low energy bills as well as a reduced need for running heating and cooling systems.

A Straw-Cell Design

We jumped into the project starting with straw bale installation. This house has what’s called a straw-cell wall, with an entire wall system behind the bales, complete with wood studs, recycled denim insulation, and exterior wood siding. The bales then are stacked on the inside of this wall, meaning that labor is reduced because you don’t have to cut or trim as many bales to fit within and around the walls’ wood frames. You also only need to apply plaster to the interior side of the bales.

Low Carbon

A great thing about the insulation materials used in this home is that they are all carbon-based, and will now be locked away in the walls of this home for a very long time. This is actually a form of carbon sequestration, one technique to keep atmospheric carbon down and help mitigate climate change. This is in direct contrast to insulation materials like foam, fiberglass, and mineral wool, which consume a lot of energy to create. This means that the manufacture of those materials produces a lot of greenhouse gas emissions, upping their carbon footprint.

Healthy, Natural Plasters

Applying a base layer of clay plaster at the work party.

Our next step was to start the plasters. A base coat of local red clay was applied to cover the bales first. At a fun summertime work party hosted by the family, we added a leveling coat which will provide the base and shape for the finish plasters. We introduced some folks to the techniques and tools for mixing and applying natural clay plasters and played in the mud with good friends. We also started to build out the windowsills into their final shape using a lime and clay mixture with lots of straw for strength.

Ben talks building with some volunteers while others work on shaping the windowsills.

The finish plaster drying around the laundry room window.

The final wall finish was customized to get the exact color and texture that our clients wanted, and this last, thin layer of clay-based plaster went on like a dream. Thanks to additions like wheat paste, it dries into a hard and durable finish that will last for years, and also be easily reparable in case of accidental damages.

During the wall finish process, we were preparing for and creating the tadelakt windowsills that will become perfect benches for sitting on and reading in the natural light. This Moroccan finish plaster is created from lime, which is why the base coat for the sills incorporated lime with the clay. This results in a tight bond between the materials. The smooth layers of lime were applied, soaped, and burnished using stones to create a shiny finish. The sills were then waxed as the final step to create a long-lasting surface that can withstand some use.

The burnished and waxed tadelakt windowsills have an amazing shine and reflection, as well as feeling silky smooth.

The End Result: A Beyond Green Building

We’re departing this project with lots of hope for the future which will unfold in this family’s happy, healthy, non-toxic, and environmentally friendly home. Not only will it be a beautiful space to raise a family, but also a good model for other front range homeowners looking to sustainably add some space and renew their original home.