Frequently Asked Questions
Is hempcrete environmentally friendly?
Hempcrete is carbon negative. A 300mm hemcrete® wall absorbs in its construction 40kg per m2 CO2. A typical brick and block wall emits 100kg giving a net benefit of 140kg. We use British hemp. Hempcrete is also recyclable at the eventual end of the life of the building.
How strong is hempcrete?
Hempcrete is not load bearing. In a wall the loads are supported by the frame around which it is applied. As hempcrete is lightweight and improves the strength of the timber it encases, lightweight frames and foundations may be considered. Our test cubes have given strengths of 1N/mm2 at 35 days and 2.4N/mm2 at 215 days.
Hempcrete is a combination of chopped hemp shiv and binder comprising of natural hydraulic lime and a small amount of cement. It is firm and self insulating. Hempcrete is suitable for uses such as timber frame infill,
insulation and, with the addition of aggregate, floor slabs. Hemp is a renewable biomaterial and lime is an abundant quarried material.
Hempcrete regulates the temperature and humidity of a building; in some cases completely eliminating the need for heating and cooling systems, resulting in huge energy savings. Hempcrete is carbon negative and the obvious choice for buildings aiming to achieve a low carbon footprint and the highest sustainable building code levels.
Frequently asked questions
What is limecrete?
Limecrete is a combination of natural hydraulic lime and lightweight aggregate which can be used as an alternative to concrete. This creates a breathable floor slab with a certain amount of flex.
We never include any cement or admixtures in our limecrete. This would negate the breathability.
What are the benefits to the building of using limecrete?
Limecrete is breathable. It behaves in a similar way to other natural building materials such as timber, straw and earth. Water vapour can escape through limecrete. If you have a waterproof floor and breathable walls water vapour would tend to travel up the walls, damaging them.
Limecrete is widely specified by architects to protect ancient buildings. We are fully insured to carry out work on listed properties.
This is an editorial piece that we wrote for Ecclesiastical and Heritage World.
Limecrete floors combine traditional wisdom with modern technology. Limecrete breathes with traditional building materials, respecting the original fabric of the building, and is used without a damp proof membrane. The insulation layer prevents moisture ingress while allowing damp to escape and also enables the building to be heated effectively for the comfort and health of the modern users.
We recommend the system designed and tested by Ty-Mawr Lime which uses recycled foamed glass as the insulating and anti-capillary layer. This has the added benefit of being a recycled product rather than a quarried material, further improving the ecological credentials of limecrete. Lightweight crushed pumice is used as the aggregate for an even better insulation value, which is especially important in saving energy and money when underfloor heating is installed. We have never experienced a single problem with this system in its utilisation over the past four years.