8 Best Eco Friendly Insulation Options For A More Efficient Home

Top Takeaways

>> Choosing a more natural insulation will help improve your home efficiency

>> Insulation for renewable plant sources are the most sustainable

>> Eco friendly insulation can be used in all area of your home – roof and loft, walls, floor, in your garage and garden buildings

Are you looking to find more info on eco friendly insulation options?

You’re in the right place.

There are more and more sustainable insulation types coming to the market all of the time.

It’s a good call as opting for a more natural and environmentally friendly insulation in your walls, loft, roof space and flooring will do three things:

  1. Help you lower your energy usage
  2. Save you money over the long run
  3. Improve your own environmental credentials and lower your carbon footprint

Even more, choosing a more natural type of eco insulation means you’ll also reduce your exposure to volatile organic chemicals (VOCs), which are used during the manufacturing phase.

Cheaper bills, a smaller carbon footprint and better health outcomes. What more could you ask for? Sustainable insulation has got to be the one!

Let’s take a look at the best types of eco insulation before heading into some key info and common questions.

Disclaimer: This article contains affiliate links to help with the running costs of this site. This in no way impacts the price you pay. It just acts as a little thank you to me.

8 Best Materials For Sustainable Eco Insulation

Let’s get straight into the best types of sustainable insulation for a more energy efficient home.

All of the below insulation can be used for floor, wall and roof insulation.

1. Sheep’s Wool Insulation

Sheep’s wool insulation is a superb natural product that’s becoming an ever-increasingly popular choice for sustainable insulation.

Sheep can live in some incredibly harsh environments and their wool has evolved over millions of years to keep the animal at an optimal temperature.

The formation of wool fibres, especially when compressed, helps to create a huge number of microscopic air pockets, and it’s this that gives this material its insulation properties.

Sheep’s wool is a great natural insulation choice and can be used in your walls, roof and floor.

2. Wood Fibre Insulation

wood fibre insulation roof

Wood fibre is a light, biodegradable, eco friendly insulation material. It’s made from waste wood fibres, shavings and sawdust, which makes it a much better choice for the environment.

When mixed with a binder and compressed together, wood fibre insulation panels can be customised and cut into a range of shapes and thicknesses to suit the space you’re trying to insulate.

You can buy both rigid wood fibre boards and flexible wood fibre batts depending on your needs.

It has a high heat storage capacity, makes good soundproofing, is damp proof and it’s compostable when it’s no longer needed. This is a great eco friendly insulation choice whilst also giving a valuable resource a second life.

3. Cellulose Insulation

Cellulose is a plant-based insulation.

The primary job of cellulose in nature is to give plant cell walls their basic structural strength. Getting from a plant cell wall to inside your own home walls comes via newsprint and other paper sources.

Old newspapers and other waste paper is hammer milled down to a fine dust and combined with a mineral chemical to make it fireproof (usually boric acid).

The materials that go into this type of insulation make it quite a cheap alternative, but cellulose insulation does have a good average thermal conductivity (similar to rock wool).

Because of its loose fill nature, cellulose insulation can fit into tight spaces to make sure you’re fully insulated.

4. Cork Insulation

cork insulation roll

Cork is a natural product that ticks all the boxes for me – it’s recyclable, renewable, hypoallergenic and is a extremely good insulator – you can read more on just how eco-friendly cork is here.

In fact, cork is such a good insulator that it is used by NASA to provide thermal protection for a range of spacecraft and rocket parts, including areas such as the engines and rocket boosters that have high predicted heat loads! Now that is impressive.

As well as great thermal properties, cork insulation has excellent acoustic insulation and damp proof properties.

It can be a little bit costly but this type of eco friendly insulation is incredibly effective for a long time. It comes in easy to use rolls and is one of the best sustainable option.

5. Recycled Glass Mineral Wool

knauf insulation glass mineral wool

Yes, glass mineral wool is that made from glass. One of the leaders in this area is Knauf Insulation, who also manufacture a rock mineral wool insulation.

Glass mineral wool, also known as fibreglass, is a great insulator, lightweight with excellent acoustic performance.

The glass mineral wool from Knauf contains up to 80% recycled materials. Most of this comes from a Veolia glass recycling facility.

Here the glass is turned into ‘cullet’, which is then melted down and turned into insulation. This facility gives new life to 60,000 tonnes of use glass material each year – the circular economy in action!

All of Knauf Insulation’s glass mineral wool products are made using a bio-based binder, which they call ECOSE Technology. The ECOSE technology gives their insulation a natural, earthy brown colour and saves a massive 70% energy compared to manufacturing traditional binders.

This is way better for environmental sustainability, making glass mineral wood another great insulation choice to lower your carbon footprint and improve your home efficiency.

6. Hemp Insulation

hemp insulation batt

Coming from the hemp plant, hemp wool is a renewable, plant-based and highly effective insulator.

Like the other forms of eco friendly insulation listed, hemp insulation is available in the form of batts or boards which can be cut to size for installation.

As it’s a completely natural product, hemp is recyclable and non-irritating, as well as making good acoustic insulation. You can learn all about sustainable hemp here.

On the downside, if used in damp scenarios, you’ll need to apply a vapour barrier which can add to the already slightly more expensive cost.

7. Cotton Insulation

Sometimes referred to as cotton/denim insulation, the raw materials of this one come from thrown out jeans and clothing.

Unfortunately you can’t just chuck your old jacket or 501s into the cavity, the materials need to be shredded and recycled down into thick sheets that can be cut into the correct size. The fibres and air spaces help give cotton products good heat insulation.

You probably won’t be surprised to know that this is one of the more costly eco-friendly insulation alternatives and is much harder to find on the market.

8. Recycled Plastic Insulation

recycled plastic insulation roll

Plastic isn’t a sustainable material, but using post-consumer recycled plastic is a great sustainable insulation material. An excellent way to be more environmentally friendly at home.

Recycled plastic insulation is made from around 95% rPET plastic bottles. You can read a little more about plastic recycling here.

This material is affordable, long-lasting, VOC free and often made in the UK. It can be used to insulate floors, walls spaces and as eco loft insulation.

9. Recycled Rubber

Primarily made from recycled tires, recycled rubber insulation is a new and innovative type of insulation.

It brings many benefits to the table, or to the space it’s insulating should we say.

Rubber is a remarkable materials that can withstand high temperatures, moisture and pests. It’s also really durable meaning that it’s got a long lifespan.

Recycled rubber insulation is flexible and can be easily cut and shaped to fit in irregular spaces. A further benefit is that it’s excellent at absorbing sound and can help to reduce noise levels from the outside.

I’d say recycled rubber is a great, effective and sustainable insulation choice.

The issue with traditional insulation materials

The type of insulation you go for is an important consideration. It’s primary job is to create a more energy efficient home.

On the whole, all good insulation will help you save energy and money. No matter what the material used, this is always a valid point.

It’s thought that good insulation can save 35% in heating costs. When heating costs can go into the £1000s in 2023, 35% is huge.

Energy intensive to produce

Insulation types that do perform well such as polystyrene (including foam board and spray) and fibreglass insulation (also called glass wool) come with energy-intensive, resource depleting manufacturing processes.

Creating these forms of traditional insulation can use up to 10 times as much energy as their eco friendly alternatives.

When it comes to energy and cost efficiency, it makes much more sense to invest in high levels of insulation for your home, rather than investing in fancy heating and cooling technologies.

Hazardous materials

Many manufactured products also contain irritants and potentially hazardous fibres that are linked to health issues, such as eyes, skin and respiratory irritation.

These are known as VOCs and can be found in other chemical-heavy products. Carpets and even new furniture will all off-gas VOCs at the start. That smell when you paint the walls? Yes that’s VOCs being emitted. A reason why eco friendly paint is a good idea.

As well as considering the performance side of insulation – how it impacts the efficiency of your home’s energy performance and how much money it saves you – weighing up sustainable insulation needs to account for how the product is made.

Namely, do they require resource depleting materials? How much energy goes into making them? Do they contain harmful substances?

What Makes insulation Eco Friendly Then?

Eco friendly insulation is a type of insulation manufactured in a sustainable way and that can be recycled or reused afterwards.

Eco insulation will reduce your need for heating when it’s cold and help to keep your home cooler in the warm weather. Exactly what you want.

There are four main areas that need to be ticked to be classed as eco friendly insulation:

  1. Low embodied energy – this means the product requires little energy (and carbon) to make
  2. Recyclable or compostable – so it won’t end up in landfill
  3. Uses sustainable materials – the raw materials need to be readily available and sustainable over the long term, which means the earth’s resource of the material won’t be depleted
  4. Safe, non-hazardous materials – anything used in the product shouldn’t cause harm or irritation to people who work with it or have to live with it

Many of the eco friendly insulation options use natural fibres as the primary material choice.

In the UK, the home insulation market is worth over £800 million a year, however, only about 1% of that is made up of natural insulation products.

This is quite a staggering statistic. It’s one that I hope is significantly improved over the next few years as more people start to choose greener living options and as the government tries to meet its carbon emission goals (we hope!)

wood burner in shepherds hut

If you’ve got an Ecodesign wood burner, you’ll want to make sure you’ve got great insulation to keep all that warmth in.

Is eco friendly insulation any good?

It’s all good and well being more sustainable, but how does the product perform. Is eco friendly insulation any good?

The good news is that eco insulation performs very well.

It’s all in the R-value. This is a measure of how good a material is at resisting the flow of heat.

In short, the higher the R-value, the better it is at resisting heat flow. This means it’s a good insulator.

Many of the eco friendly insulation materials on the list below have an R-value that’s just as good, if not better, than your typical polystyrene-based (XPS, EPS) insulation.

Benefits of using environmentally friendly insulation

Aside from offering good thermal insulation properties, there are plenty more benefits of using natural insulation in your home:

  • Low to zero toxins and irritants
  • Safe to handle
  • Hypoallergenic
  • Much less risk of health issues across lifetime use
  • Good levels of acoustic insulation
  • Lower carbon footprint
  • Reusable
  • Recyclable
  • Zero waste from the offcuts
  • Treated to fire safe
  • More likely to be locally manufactured

Where is sustainable eco insulation used?

eco friendly roof insulation
Eco friendly roof insulation

Eco insulation materials is used just like any of type of insulation. There are three main places where eco-insulation is used:

  1. Roof and loft space – 25-30% of heat lost here
  2. Wall space – 35-40% of heat lost here
  3. Floor space – 10-25% of heat lost here

The rest of heat loss occurs from draughts, gaps and windows.

Timber framed homes, which includes many tiny houses and shepherd huts, need wall insulation to occupy the space between the timber stud walls.

This type of insulation mostly comes via a batt, board or roll that is cut to size before installation.

If your home is constructed with a solid structure, such as stone or cob, the thermal mass property of these materials will work as insulation as it’s not possible to insulate in the convention way unless another layer is added to outside or inside.

Eco roof insulation

Sustainable loft insulation will generally work in the same way as timber framed walls.

You’ll be able to use insulating rolls or bags to fill the gap, although it will depend on the type of roof structure your home has.

Some of the best materials for eco roof insulation are listed below and include sheep’s wool, wood fibre, hemp and cellulose.

These can all be cut to shape and formed so that they fill the space perfectly.

Eco friendly floor insulation

Don’t forget about insulating your floor too!

Although heat rises, a percentage of it can still be lost through the floor. It’s thought at least 10% of heat can dissipate away through your flooring, even going up to 25%. This is a lot!

Again, the sustainable materials below, such as sheep’s wool, wood wool and especially cork (a material I love), can help insulate your floor.

If you have a smaller construction, like a hut, eco pod, cabin or tiny home, it’s crucial to properly insulate the floor to make your home as efficient as possible.

Much like your walls and roof, batts, rolls and bags are the most common ways to insulate your floor space.

Insulating other areas of your home

It’s now good practice to install insulation in other areas of your home.

For example, adding insulating your garage, as well as insulating your conservatory can help make these less comfortable areas more temperature-steady.

FAQs On Eco Insulation

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Ben & Murphy Peaks Mam Tor

I’m the Creator and Editor of Tiny Eco Home Life. I write and publish information about living a more sustainable, environmentally friendly life. Away from the laptop, I love spending time in nature and with my young family (plus Murphy the dog!). I write and send out the Eco Life Newsletter.