Eco-friendly builds are widely believed to cost 17% more than regular builds, according to a report released by the World Business Council for Sustainable Development.
Yet there are conflicting studies and The Renewable Energy Hub suggests they are only 2% more expensive.
Either way, a building that’s designed to use less energy and water will quickly recoup the initial outlay, as they'll be a lot cheaper to run long term.
Why are eco-friendly builds more expensive?
While eco-friendly builds are rising popularity, there aren’t enough people purchasing sustainable products right now.
When a business has low demand for a product, they cannot manufacture it at scale, which would help to bring the costs down.
When that demand increases, businesses can produce more and lower the price to get the profit they need. So it basically boils down to levels of demand.
Eco-friendly materials can also be more expensive because the companies which produce them follow sustainable practices.
In some cases there are also complex manufacturing processes involved or the raw materials simply cost more to source.
However, as some products utilise waste materials such as agricultural straw, this isn’t always the case.
And sometimes, the sustainable product will be the cheaper - as well as the greener - option.
“As knowledge and usage are expanding, costs are going down,” says Ben Ridley, director of Architecture for London.
“Picking the right materials gives you lower maintenance costs and a healthier environment. Therefore, in the long run, it benefits both the homeowner and the property.”
How can I make sure my renovation is eco-friendly?
The first step to using eco-friendly building materials is making sure that they’re incorporated into the design of your project.
“It’s actually quite easy to start swapping concrete and steel for stone and wood,” says Ben Ridley, director of Architecture for London.
“Steel and concrete have some of the highest levels of embodied carbon and are often the default choice when building.”
Where can I buy eco-friendly building materials?
“Finding eco-friendly building materials is still a bit of a challenge as there’s not one single and easy-to-find product rating,” says Gregory Smith at PriceYourJob.co.uk.
“You can look to see if products meet the environmental standard of ISO 1400, but this can be time consuming.”
Handily, there are organisations available that can help with the sourcing.
“The Alliance for Sustainable Building Products and GreenSpec have their own databases of eco-friendly materials to help you find everything from bricks and blocks to tiles and insulation,” says Smith.
And dedicated building merchants stocking greener materials have emerged, including:
If in doubt, salvage:
Using reclaimed materials from demolition sites, refurbishments and other building sites cuts down on waste and gives old materials a new lease of life.
You might discover a bargain or manage to take something off someone’s hands for free.
Here’s where to look:
What are the most eco-friendly materials to choose when renovating my home?
1. Sustainable wood
It's easy to find sustainably sourced or reclaimed timber for structural use in your build or extension.
Look out for an FSC (Forestry Stewardship Council UK) or PEFC (Programme for the Endorsement of Forest Certification) logo when buying.
As always, buying local is best so the wood doesn’t need to be shipped a long way.
2. Eco insulation
Insulation is king. It keeps the warmth inside in winter and the heat outside in summer.
But, not all insulation methods are eco-friendly. Avoid the fibreglass options which are fossil-fuel intensive to produce. Similarly, foam boards can be derived from petroleum.
The solution? Sheep’s wool, hemp, cork, wood wool and cellulose insulation.
Our favourite is sheep’s wool because it's totally natural, recyclable, filters the air and is moisture regulating.
3. Straw bales
It's not as crazy as it sounds. Entire eco-friendly apartment blocks have been built using straw bales.
Straw bales can offer structural support to a building. They can also be used as insulation inside a timber frame.
You can then plaster your straw walls with lime, clay or a cement and lime mix.
Straw is a renewable material. This means it can be harvested and re-planted with minimal environmental impact.
Better still, this type of straw is actually a waste product. So rather than release more carbon by burning it, it can be used to make your home cosy and warm long term.
Bamboo is an incredibly strong, versatile building material. In some countries, it is used as scaffolding poles because it grows so tall.
It's biodegradable, antibacterial and fully sustainable because it has a rapid growth rate. It's also able to replenish itself after harvesting in just three to five years.
Because it's a lightweight material, bamboo has a lower carbon footprint to import too.
Watch out for heavily processed forms of bamboo which use chemicals.
As we know, concrete is a major offender when it comes to carbon emissions. A more sustainable alternative that can do a similar job is Ashcrete.
More than 90% of the substances contained in Ashcrete are recycled.
It contains fly ash (a waste product produced during coal power generation), along with borate, bottom ash and a chlorine compound.
Like cement in concrete, the fly ash reacts with water to produce a strong, sturdy material.
Imagine breeze blocks made out of a fibrous, more natural-looking substance and you've got hempcrete.
These blocks contain a mixture of sand, hemp fibres and lime and are used as both construction blocks and insulation.
Hemp is a botanical class of cannabis sativa cultivars and is among some of the fastest-growing plants on Earth – which makes it sustainable.
Hempcrete blocks are light and easy to work with. It's a breathable material that's both fire and pest-resistant, as well as a strong insulator.
If straw bales were an eco-friendly stretch too far, Enviroboard could be the next best option.
These panel boards can be used in a versatile way to build homes, but they’re made from straw waste.
Manufacturers claim that just 1% of energy is used in the production of Enviroboards when compared to OSB and Gypsum board production.
Better still, they are 100% renewable and manufactured at a scale which keeps costs down.
They can be used to build exterior and interior walls, ceilings, sub-flooring, roofs and more.
8. Clay bricks
Like wood, there’s a reason clay bricks have been used in construction for a very long time. Not only are they attractive to look at, easy to work with and breathable, they’re eco-friendly too.
The bricks are simply made of clay and water and contain no chemicals or other synthetic components. As a result, they are recyclable and can be returned to the earth.
The manufacture of clay bricks does have a carbon footprint, but it’s far lower than other mainstream building materials.
Plus, bricks can be reclaimed and used in new building projects.
Newspaperwood reverses the paper-making process, returning our daily news into wood form.
Processed into 0.6mm veneer sheets, the material shows a grain structure created by countless layers of newspaper.
Quirky upside: you might still be able to see traces of newspaper articles and words on your floors or walls.
Another great product that has jumped on the “let’s-put-crete-in-the-name” bandwagon, is Timbercrete.
As the title suggests, Timbercrete is made from timber waste products like sawdust and offcuts.
Amazingly, it actually traps the carbon that would otherwise end up as a greenhouse gas.
You can buy Timbercrete bricks, blocks, panels, pavers and cladding. It looks similar to sandstone but its products are lighter than comparable construction materials.
Is it worth using environmentally-friendly building materials?
The way we build and the materials we choose have a direct bearing on climate change.
Building and construction processes are responsible for nearly 40% of global greenhouse gas emissions worldwide every year.
More than half of these emissions are generated by just three materials – concrete, steel and aluminium.
The UK is legally bound to reach Net Zero emissions by 2050. If we are to meet this target, the way we build homes and the materials we choose will need to change.
There are many things that need to be done at industry-level to decarbonise our existing housing stock.
But anyone building homes or extensions today can make a big difference in how they choose to do it.
Chris Harvey, of heating specialists Stelrad.com, says: “While not every element of a new-build, extension or renovation can be changed, there are some positive ways to approach minimising waste, energy and overall reducing your emissions.
“Consider all options and speak to trusted builders, charities and companies for advice on making simple swaps, whether it’s materials or appliance technology.
“Ultimately, if budgets allow, the more eco-friendly materials you use, the more energy efficient your home will be, positively contributing to your long-term finances.”