How a material, fixture or finish is actually manufactured, and the energy and water it consumes in that process, makes a difference to its sustainability.

In this episode, I share how to think about manufacturing efficiency when making selections for your renovation or new build.

Listen to the episode now.

Hello! This is Episode 431. This is Way #31 of the 44 Ways to Create Your Sustainable Home series, and we’re wrapping up Section Six: Choosing Materials, Fixtures and Finishes.

In this section of the ‘44 Ways’ series, I’ve been covering one specific criteria for choosing materials and products per episode. And so far, we’ve covered choosing for longevity and durability, a low carbon footprint, low VOCs and low tox, recyclability and low waste, and choosing from companies with sustainability missions.

Way #31 is: Choose Based on Efficiency of Manufacture.

This is where your sustainable selection criteria can be shaped by how a material, product, fixture or finish has been made, and whether it is energy efficient in its manufacture. And also reviewing whether it will improve your home’s energy efficiency.

Most products we use in building and renovating our homes have quite a high level of processing. Even though most homes are built from fairly conventional and consistent materials of concrete, timber, brick, steel, blockwork, plasterboard, metal, tile… the source products that go into this all need to be processed quite heavily to reach our homes in their usable state. 

Even a stick of timber sourced from a plantation forest will go through a fair amount of handling and treatment to reach your construction site in the state needed for it to be suitable to include in your home.

And all of that sourcing, manufacturing and processing takes a use of resources, namely energy. It also often uses water as well in some way.

So, it stands to reason that a manufacturing process that uses less energy, less water, and converts more of its raw material input into finished product is going to be considered more efficient. 

And that efficiency then does impact the product’s sustainability.

There are some parts of this I’ve covered in earlier episodes: the embodied carbon of materials in Episode 427, Way #27, and the importance of recycled content for closing resource loops in Episode 429, Way #29. So, in this episode, I thought I’d share some of the aspects of manufacturing efficiency that haven’t come up yet.

When we talk about the sustainability of a material or product, it’s easy to focus on the material itself: its ingredients, how it’s extracted, how it’s chemically treated. However, a manufacturing facility running on renewable electricity is in a different position from one running on fossil fuel supplied power. 

This is something that can be declared by companies individually. It will impact the life cycle analysis or LCA of a product or material, and also be included in their Environmental Product Declaration or EPD.

It can be difficult for some manufacturers to run their facilities solely on locally produced renewable energy using solar power generation, as it can be too unreliable for the intense power needs of certain manufacturing processes. 

However, I have seen manufacturers use the local energy grid but pay for green power, so they let the energy provider manage the renewable side of it, whilst satisfying that benchmark of using renewable energy for their manufacturing needs.

In any manufacturing process, some proportion of raw material input becomes waste rather than product. Off-spec batches, offcuts, process losses, and rejected product all represent material that was extracted and processed but never became anything directly useful. Some manufacturing processes can create waste products that are toxic, and so the disposal of those becomes an important consideration in the sustainability of the manufacturing process as well.

Some of the most interesting newer building materials on the market are essentially built on this principle: they’re taking what was previously production waste from another industry and turning it into a building product.

The construction industry can be a water consumptive one. An Acumen note published in 2022, written by Robert Crawford for the Australian Institute of Architects, titled ‘Embodied Water in Construction’, stated that ‘while the operational use of our buildings accounts for 12% of global water use, embodied water now represents most of the water used across the building life cycle.’

I’ve been talking about carbon footprints, which largely relate to the energy footprint, or embodied energy, of a product. However, there’s also something known as a ‘water footprint’ or embodied water, which looks at the water requirement across all stages of its sourcing and production, as well as the water requirement for its repair, replacement and disposal.

If we look at a product like structural steel, the EPiC Database which measures the embodied water of construction materials, cites that steel has an embodied water value of 37.1L per kilogram of steel. 

A 6m long steel beam that’s a 250UB or Universal beam can weigh about 180kg, so that’s over 6,600L of embodied water. 

Nylon carpet has an embodied water value of 1,149L / m2 of carpet. Interestingly, kiln dried hardwood timber has an embodied water value of 25,332L / m3.

Recommendations for reducing and optimising the embodied water of a product or material include: 

• using less of a product
• sourcing materials and products from manufacturers that have water-efficient production practices
• specifying durable, long-lasting materials and products, and also ones that have been used previously or have high recycled content, or high potential for reuse or recyclability.

This episode wraps up Section Six of the 44 Ways series. We’ve covered six criteria for choosing materials, fixtures, and finishes with sustainability in mind. These are the questions you can ask when making your selections.

It will be very difficult, if not impossible, for you to satisfy all six criteria in your sustainable selections.

And that can overwhelm and frustrate you.

Don’t let that dissuade you from prioritising sustainability when selecting materials, products, fixtures and finishes.

The reason I share six with you is to provide you options and determine what resonates most with you.

In this Episode, I cover:

• What manufacturing efficiency actually means, and why it sits alongside embodied carbon and recycled content as a sustainability selection criteria
• Why the energy source powering a manufacturing facility can matter as much as what the product is made from
• What happens to raw materials that don’t make it into the finished product
• The ‘water footprint’ or embodied water concept, and the numbers behind certain materials
• Recommendations for reducing embodied water through material choice, sourcing, durability and recycled content
• Consideration of your builder’s site water, waste water and stormwater management
• The questions to ask your designer, architect, product reps and builder so manufacturing efficiency gets factored in
• Real HOME Method member examples of choosing one criteria as a priority, and how that shapes their whole selection process

Plus a whole lot more.

LISTEN TO THE EPISODE NOW.

Episode 426, on choosing for longevity and durability >>> 44 Ways #26

Episode 427, on choosing for low carbon footprint >>> 44 Ways #27

Episode 428, on choosing for low VOCs and natural or low-tox ingredients >>> 44 Ways #28

Episode 429, on choosing for recyclability and low waste >>> 44 Ways #29

Episode 430, on choosing from companies with sustainability missions >>> 44 Ways #30

Episode 256, on choosing building materials >>> Choosing Building Materials

AIA Acumen Note on embodied water in construction (paid or member document) >>> Embodied Water in Construction

Environmental management certification standard >>> ISO 14001

University of Melbourne database of embodied environmental data for construction materials >>> EPiC Database

A free guide to simplifying sustainability across research, planning, design, materials, and building, from Amelia Lee’s 30+ years in residential design and construction >>> 44 Ways to Create a Sustainable Home

Access the support and guidance you need to be confident and empowered when renovating and building your family home inside my signature online program >>> HOME Method