One major challenge that the construction industry is facing is how to use more sustainable and environmentally friendly. One such material that is gaining popularity is hempcrete, a carbon-negative material that offers sufficient thermal insulation capabilities in all climates.
Hemp is a highly versatile plant. It grows fast (within 90-120 days), it does not require pesticides and it can withstand all weather conditions. From seeds, to stalk to leaves and fibers, each part of this plant can be used in our world. It is said there are over 25,000 uses when you consider it as a replacement for popular materials that cause harm to our planet (such as plastic).
One such amazing replacement is using the plant for building hemp houses, buildings and structures. Houses built with hempcrete (which is a mixture of hemp hurds, lime and water) consume less energy, creates less waste, and has a carbon negative impact on the environment. It also acts as a natural insulator to keep the interior temperatures controlled no matter the season. In this article, we’ll dive deeper into these insulation benefits.
Insulating With Hempcrete
Hempcrete was originally designed to be a repair material for old-straw composite buildings which required a breathable render material. The idea then evolved into a hemp-lime insulation material. However, unlike concrete, it is not a load-bearing material and requires an additional framework to resist the load. For those reasons, using the material for insulation purposes is currently one of its most popular applications.
U-value is a measurement which determines how much heat passes through a particular material. The best insulating materials have a U-value of close to zero (the lower the better). Hemp has a U-value of 0.40, which outperforms other insulating materials like wool and cotton.
Moreover, hemp’s R-value (which measures the resistance of a material to heat flow) stacks up to its competition of alternative fibrous insulation products. The higher the R-value, the greater the insulating power of a material. Hempcrete’s R value of 3.5 per inch makes it an incredibly efficient insulating material.
Moisture Handling And Resistance Property
The uniqueness of hempcrete among the plant-fiber insulation materials is its ability to maintain its standard in humid conditions. Hemp hurds (like other plant-fiber insulation options such as wood, cellulose and straw bale) have the ability to store a great deal of moisture due to its porous structure.
The moisture from the air gets accumulated on the large internal surface of the plant fiber and gets absorbed into its cellulose structure. This storage capacity allows the material to absorb excessive moisture and release it when the conditions allow.
Hempcrete also displays great resistant properties to water, fire and molds. This is majorly due to the lime binder. Lime is said to have a high pH value and is a natural antimicrobial and antifungal material. Thus, a coating of lime binder around the hemp hurds creates a resistance to the development of molds. This holds true even when the same levels of humidity and temperature allow the occurrence of molds on other insulation materials.
Not only temperature-controlling during summers and winters, hempcrete also provides efficient insulation when it comes to factors like sound. Its acoustic insulation properties make your walls, roof and floors sound-proof. With the use of hempcrete blocks for your walls, external and ambient noise will significantly reduce. It acts as a real sound trap and helps in dampening the majority of sound waves, thus acting as a barrier against noise pollution.
Hempcrete acts as an incredible material when it comes to insulating the roof of buildings. You can opt for hempcrete blocks because their application is quick and easy and the insulation prevents the roof from overheating during summers. It also does an excellent job of maintaining heat during winters.
Hempcrete also acts as a natural insulation material for walls. The walls are made together with a frame of other materials (like wood) that act as vertical support to the mixture. This is because hempcrete’s density is low when compared to traditional concrete. Despite this, the walls will still offer high insulation value, rock-like strength, durability, and resistance to pest, mould, water, and fire.
The use of hempcrete on the ground provides effective insulation to the floor of your house. It is also suitable to support a screed such as cement, lime or clay. When used on floors, it provides excellent comprehensive strength, underfloor heating and cooling, and higher energy efficiency over time.
Hempcrete can also prove effective for external insulation. By applying to the exterior of the wall of a home, it can achieve a high insulation performance for the entire structure. Exterior hempcrete insulation can be beneficial in many ways: avoiding any thermal bridge, aesthetic improvements, easy implementation, and reduction of indoor disturbance, to name a few.
If you are planning to extend your house, hempcrete can be a very efficient material to give your house extended insulation. With hempcrete extension insulation, the temperature of your living space will regulate naturally without any change. You will also receive good acoustic insulation and a healthy living space with comfort in any weather (along with all the benefits mentioned above).