Frequently asked questions

IndiNature uses natural fibres including locally grown industrial hemp – a crop grown historically in the UK.

Industrial hemp is not the same as the drug variety of cannabis - it contains zero drug content and has more fibres.

We use industrial hemp for many reasons. One key reason is that , unlike synthetic fibres, hemp is exceptionally good at transporting water vapour out of buildings to create good indoor air quality and to preserve building structures - ‘breathing’ like traditional construction materials are meant to do.

Secondly , it is a very strong and stiff fibre which means in an insulation matt its rigidity resists slumping in walls.

Thirdly it is incredibly good at capturing carbon, much faster than timber, and is good for regenerating soil on farms.

Unlike synthetic fibres, natural fibres like hemp have some light thermal mass which slowly absorbs and releases heat - which means buildings not only stay warm in winter, they can be kept cool in the summer. This also passively attenuates hot and cold ‘peaks’, creating nice and even temperatures indoors in all seasons - making buildings comfortable and healthy.

Yes, industrial hemp captures carbon as it grows and photosynthesises at a very fast rate, growing to 2-3 meters tall in a season. Between 8 to 15 tonnes CO2 per hectare are captured by the plant (European Industrial Hemp Association, EIHA).

An independent Carbon Life Cycle Analysis (cradle to gate) for IndiNature products demonstrates from the farm to end of processing, the materials are net carbon negative. Not only due to the crop CO2, but also because we use a relatively small amount of energy in production compared to synthetic mineral wools.

Adding IndiTherm to buildings then stores the carbon in the building. If used in place of rockwools, building projects can save a quarter of a tonne of CO2 per pallet of IndiTherm used. 4.4 tonnes of CO2 can be saved on a full house build.

You can find R-values on each specific technical data sheet for IndiNature products.

IndiTherm is dense and semi-rigid so resists slumping exceptionally well - this is a unique advantage. This is one reason we use hemp fibre - it is very strong and stiff - you can stand an IndiTherm batt up on end and it won't fall over, yet it is flexible enough to friction fit into voids.

Acoustic absorption has been tested at:

50mm αω 0.65(H)

70mm αω 0.85(H)

100mm αω 1.00

140mm αω 1.00

Natural fibre insulations are known to have good acoustic properties. We can supply both low density and higher density products to suit your system needs.

Natural fibre insulation made from hemp, flax and wood fibres has been used in Europe in thousands of buildings for over twenty years and there is no history of insect issues. Insects are not attracted to the materials and they do not provide a food source for insects.

Rodents are not attracted to the hemp or flax and they are not a food source. There is no history of this as issue in the tens of thousands of buildings in Europe made with these materials.

Natural fibre insulations are championed because they help prevent rot and decay in buildings. We use hemp fibre in particular because of its durability and its exceptional ability to transport or 'breathe' vapour out of buildings. Unlike mineral wools and petrochemical foams which can trap rather than transport moisture, natural fibres help preserve buildings which is why they are known to be appropriate and preferred for historic and traditional building retrofits - for both timber or masonry.

Hemp fibre was historically used for navy ship anchor ropes, rigging and sails because of its strength and ability to resist rot.

Bio-based buildings have a history of lasting for centuries when built well.

Please follow the install guide recommendations to optimise performance. A 50mm air gap is required between our products and roofs or wall rainscreens to allow safe vapour transport out of the building.

Our technical team is also available to advise on detailing and offer condensation risk analysis.

All insulations, whether synthetic like mineral wools or natural like IndiTherm, need to be installed correctly to allow optimal bio-resistance. Mold is not an issue when building materials are installed correctly. Please see our Install Guide for correction installation.

For protection against poor installations, the product is warranted by the Installation Assurance Authority.

This is possible but not always advised - sometimes membranes will be recommended. We recommend the usual condensation risk analysis - our distributors can help with this or you can contact us directly to help with calculations and modelling.

Please refer to our Install Guide for recommendations or get in touch with our technical team if you are unsure about an appropriate wall build up and type of membrane.

We do not recommend natural fibre insulation in an unventilated gap like a conventional double-leaf masonry or brick cavity wall.

We add a three-stage fire retardant which is not harmful to the environment to IndiNature products to ensure the fibre is covered inside the material and on both surfaces. This retardant application reduces the rate of flame spread.

We test every batch in-house to comply with the required BS EN standard.

IndiTherm has passed the UKAS accredited Reaction to Fire standard EN 13501-1 as required by the BBA with an E Class rating - the same as all other natural fibre insulations.

For smoke, the product has the best Class rating of s1.

For flaming droplets, the product has none, with a Class of d0.

Fire resistance in buildings depends on whole systems not individual products - for example internal plasterboard can add a 30 - 60 minute rating to a system.

We currently have two BBA Certificates – one for IndiTherm & the other for IndiBreathe Flex

Installations are warranted by the Installation Assurance Authority.

The product itself has completed testing in UKAS labs, with in-house quality control tests on site that comply with Harmonised Standard EN 13171:2012.

IndiTherm should be stored dry. Pallets should not be stacked. It is best to keep products stored on their sides, as provided on pallets, rather than stacking flat to reduce compression over time.

If products do become saturated from water they will dry out over time if well ventilated and performance will not be affected. Do not install wet.

IndiTherm will work in cassettes such as SIPS panels. A typical 50mm air gap will be required between insulation and roofs or between rain screens such as brick or timber cladding.

Please refer to our Install Guide for recommendations or get in touch with our technical team if you are unsure about an appropriate build up.

Yes, industrial hemp captures carbon as it grows and photosynthesises at a very fast rate, growing to 2-3 meters tall in a season. Between 8 to 15 tonnes CO2 per hectare are captured by the plant (European Industrial Hemp Association, EIHA).

An independent Carbon Life Cycle Analysis (cradle to gate) for IndiNature products demonstrates from the farm to end of processing, the materials are net carbon negative. Not only due to the crop CO2, but also because we use a relatively small amount of energy in production compared to synthetic mineral wools.

Adding IndiTherm to buildings then stores the carbon in the building. If used in place of rockwools, building projects can save a quarter of a tonne of CO2 per pallet of IndiTherm used. 4.4 tonnes of CO2 can be saved on a full house build.

Yes, our products can be re-processed on our site.

Yes. Both the soft plastic bags around our insulation batts (similar to carrier bags) and the protective plastic film (similar to cling film) can be recycled.

Some local authorities accept soft plastics through kerbside collections, so check your local council's website for guidance. If this isn't available in your area, you can take the packaging to soft plastic recycling collection points at larger stores of many major supermarkets, including Tesco, Asda, Morrisons, Sainsbury's, The Co-op and Waitrose.

Please check that your local collection point accepts both types of packaging before recycling.

IndiNature products are available through our network of specialist distributors and merchants across the UK. You can find a merchant or contact the IndiNature sales team to find a local distributor to suit your project and location.

IndiTherm is now available across the UK from specialist distributors that understand natural fibre insulation and can support you in decision-making for your project.

IndiNature can manufacture custom size products depending on order quantities and line capabilities. Please contact our sales team to discuss your specifications.