Hemp Insulation: Everything You Need to Know

Insulation, Membranes & Felts
product guide
Hemp Insulation: Everything You Need to Know

What is Hemp Insulation?

Hemp insulation is a type of insulation that is manufactured using hemp wool. Hemp wool is made from strong and woody fibres that are derived from a hemp plant.

Due to its exceptional durability, hemp wool has been used through history in sturdy applications such as clothing, ropes and even sails. It has excellent insulative properties and is very robust, so makes for a fully resistant and breathable insulation material. Hemp insulation helps to regulate thermal performance plus has high thermal mass and low conductivity so is a fantastic insulator.

Hemp wool can be made into both insulation batts and insulation boards. During the manufacturing process, cornmeal or polyester may be added to further strengthen the insulation.

So, What Are the Benefits of Hemp Insulation?

There are a number of reasons to use incorporate hemp insulation into your home construction project. From its excellent performance and sustainability to its impressive carbon storage and low maintenance growing, hemp wool has been proven as a reliable and trusted form of insulation for a wide range of properties.

Insulative Properties

Although a seemingly obvious benefit, we have to discuss the fantastic insulative properties of hemp wool. Hemp is a medium density insulation material with low conductivity and a high thermal mass. These factors enable it to retain heat, whilst efficiently regulating the building’s thermal performance. This means your home will maintain a comfortable and liveable temperature all year round. Hemp has a heat storage capacity of 1600-2350 J/kgK.

Hemp insulation is also a fantastic acoustic insulator, helping to dampen and absorb noise for a quieter home.

Environmental Impact

As it is a renewable, biodegradable and non-toxic material, hemp insulation offers fantastic environmental advantages. Hemp plants can be grown all year round with just a 100 day full growth span, making hemp insulation highly sustainable. At the end of its lifespan, it can then fully decompose with no negative impacts to the environment. Deforestation is a major problem, however as hemp takes such a relatively short period of time to grow, hemp plants may be able to replace trees as a raw material source.

Little energy is used during the production process, further lessening environmental impact. On average, hemp wool insulation requires 14 times less energy to produce than polyurethane that offers an identical level of thermal performance. It is the perfect material for ‘zero carbon’ homes as it absorbs more carbon than it consumes during construction.

Beneficial to Other Crops

As hemp plants are known as a ‘break’ crop between other crop rotations, they allow the soil to regain nutrients that it needs to grow healthy cereal crops. As the plant grows, the plant matter falls into the soil and replenishes it. Once harvested, the remaining elements of the hemp plant can also be added back onto the land to enhance further crop growth.

Reduces CO2

Known as ‘nature’s purifier’, hemp plants have the ability of take carbon dioxide from the atmosphere, giving us cleaner air to breathe. It is even more effective than trees. On average, for every tonne of hemp that is grown, around 1.63 tonnes of CO2 is captured from the air.

Easy Growing

The hemp plant can easily grow in very diverse conditions as it requires only very minimal levels of water plus doesn’t rely on artificial irrigation. This means it can be grown fully without the use of any chemical pesticides or herbicides. Exposure to pesticides and herbicides adds to the amount of toxins and pollutants in the air and water, so minimising usage helps to combat a range of environmental and health issues.

No scent

Thankfully, hemp insulation can be fitted into your property without worrying about any strong odours. It comes free of adverse and noticeable smells so you can enjoy high-quality insulation, minus a stench. 


Hemp is a breathable, hygroscopic material which means it helps to control humidity by absorbing condensation. It allows vapour to travel through the insulation, protecting against moisture damage. This makes it ideal for use with timber framed structures.

Non Harmful

For those concerned about possible health effects, hemp insulation has no adverse effects and is non-irritating on skin and lungs. It does not contain harmful substances so is completely safe for the home plus is protected against mould, bacteria, pests, termites and fungicides.

Fire Resistant

As hemp insulation is fire resistant, it may char but is will not burn. This makes it a safe and practical insulation material for the home. Hemp can be treated with non-toxic flame retardants like silica for enhanced protection.


Hemp insulation is also waterproof and performs similar to a towel or sponge when exposed to water. Unlike alternative insulation materials, it is unlikely to break apart when wet.

Robust & Firm

With a dense and resilient yet lightweight build, hemp insulation is a durable material that maintains a firm structure when placed between wall studs. It is long-lasting and less prone to slouching and compression over a long period of time.

Easy Installation

Hemp insulation is available in batts or boards and can be easily cut to size to closely connect and avoid thermal bridges. The fitting method itself is straightforward, quick and not messy.


Hemp insulation is suitable for a variety of different applications within the home including sloped roofs, wooden floors, ceilings, walls, facades and more.

To Conclude

Although a relatively new insulating material, hemp has a proven list of high-grade benefits that makes it more than fit for the job. It is a safe, practical and eco-friendly option perfect for use in a multitude of properties. Why not give it a go in your home and experience the fantastic benefits for yourself?

For more information on natural insulation, read this blog to learn more about the benefits of natural insulation a read.

Alternatively if you have any further questions or queries, don’t hesitate to get in touch with our friendly customer service team who will be more than happy to help. Just give them a call on 01295 565565, email [email protected], or leave a message in our handy live chat.

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