In Partnership with

Natural Building Material Experts

We’ve partnered with ISOHEMP to bring clients, contractors and Architects an innovative natural building system.

Timber Lot are experts in building with natural materials. Breathable, bio-based materials for new builds and retrofit to historic and traditional building conservation. Our founders have over 70 years of construction experience between them.

Benefits of IsoHemp

Some of the benefits of our bio-based systems include:

  • Low embodied carbon
  • Breathable, healthier buildings
  • Net Zero buildings
  • Comfortable, warmer, moisture regulating technologies
  • Simpler wall build-ups and processes

Contact us for a quote.


Call Us On: 01672 500 260


IsoHemp hemp blocks are designed for creating insulating envelopes, partition walls, and counter-partitions in non-load-bearing glued masonry. Their versatility makes them a favorite for new constructions and renovations across various projects, including single-family homes, collective housing, and tertiary buildings.

These blocks are apt for constructing residential houses, enhancing existing walls internally or externally, and for industrial partitioning and apartments, facilitating adherence to low-energy, very low-energy, and passive house standards. They are technically approved, meeting all relevant European regulations.

The range includes solid blocks in various thicknesses (7.5cm to 36cm) and machined blocks (holed and U-blocks) in 30cm and 36cm thicknesses.

IsoHemp hemp blocks offer five key benefits for construction projects:

  1. Thermal Regulation: They maintain a consistent indoor temperature by storing heat in winter and preventing overheating in summer, acting as a thermal buffer.
  2. Humidity Regulation: Highly permeable to water vapor, they stabilize indoor humidity levels, making them ideal for renovating damp buildings and ensuring the preservation of structures.
  3. Acoustic Insulation: These blocks significantly reduce external and ambient noise, acting as sound traps to dampen sound waves and protect against noise pollution.
  4. Fire Resistance: Complying with fire safety standards, hemp blocks provide a simple, effective fire protection solution, offering up to 2 hours of fire resistance depending on the block’s finish and thickness.
  5. Eco-Friendly: Manufactured from 100% natural, locally sourced materials with a low-energy process, they have a positive carbon footprint, with each pallet storing 100kg of CO2.

These attributes make IsoHemp hemp blocks a comprehensive, natural solution for sustainable construction and renovation projects.

IsoHemp hempcrete blocks are installed using a method akin to traditional cross-jointed masonry, joined with a specially formulated IsoHemp adhesive mortar for rapid application. Despite their large size, these blocks are lightweight, facilitating ease of use on construction sites. Detailed instructions for their application can be found in the IsoHemp hemp block implementation guide or through participation in training sessions offered by IsoHemp. Additionally, instructional videos are available on IsoHemp’s YouTube channel.

Hempcrete blocks have versatile applications, serving as an effective solution for various construction needs in both new builds and renovations. They can be utilized for:

  • Creating secondary walls
  • Filling in masonry
  • Partitioning spaces
  • Insulating interiors and exteriors
  • Constructing floors and roofs
  • Extending existing structures

Regarding finishing, IsoHemp offers a natural PCS coating for a smooth, white surface indoors that’s economical and paint-ready. Limestone and clay plasters are also compatible for interior finishes. For exterior applications, mineral plaster and all types of cladding can be directly applied to the blocks. Furthermore, a double masonry approach, incorporating bricks or country stone, can be achieved using mechanical ties, expanding the aesthetic and functional possibilities of hempcrete block construction.

Hempcrete, a mixture of ProKalk limestone and IsoHemp hemp, serves as both interior and exterior insulation for existing structures and as infill for wooden frames in new builds. It offers versatile application methods, including pouring into wooden formwork or direct wall application for a seamless finish, though the latter is recommended for professionals due to its skill requirement.

In scenarios where walls are uneven, hempcrete complements IsoHemp hemp blocks by filling gaps, ensuring a level insulation layer. This material provides several benefits, including maintaining consistent indoor temperatures, moisture regulation, and significant sound insulation, with noise reduction indices between 37 and 45 dB depending on thickness. Its ease of use in renovations and on-site preparation speed are additional advantages.

Making hempcrete involves a simple process of mixing IsoHemp hemp, ProKalk limestone, and water. The recommended method involves starting with 80% of the water and limestone, waiting for a milky mixture, then adding hemp gradually to achieve a pasty consistency. The final 20% of water is adjusted as needed. Care must be taken to avoid overmixing to prevent clumping. Usage should follow promptly after mixing. For further guidance, IsoHemp provides tutorial videos online.

IsoHemp hemp and ProKalk limestone are two key ingredients for creating hempcrete, a lightweight, insulating concrete ideal for on-site preparation.

IsoHemp hemp is a high-quality aggregate that, when mixed with ProKalk limestone, yields a performant insulation material. Its benefits include seamless integration with existing structures, compatibility with ProKalk for assured performance, minimal dust production, local sourcing, and applicability in both renovations and new constructions.

ProKalk limestone is a pre-mixed binder designed specifically for hempcrete production. It consists of hydraulic lime and aerated limestone, creating a mixture ready for immediate use on-site.

Benefits of ProKalk limestone include:

  • Its 100% natural composition
  • Compatibility with both mixers and spray machines
  • Effective insulation against temperature extremes
  • Moisture regulation within the building envelope

PCS interior plaster is an economical, durable, and high-quality plastering solution, consisting of a blend of natural plaster, limestone, and sand. It’s perfectly suited for walls and ceilings in both renovations and new constructions.

This plaster enhances indoor living spaces by combining the ease of application of natural plaster with limestone’s moisture-regulating properties, ensuring a healthy and high-quality interior environment.

Key benefits of PCS interior plaster include:

  • Creates a comfortable and superior interior atmosphere
  • Healthy, natural, sustainable, and cost-effective
  • Simple application process
  • Delivers a white, smooth finish ready for painting
  • Breathable surface coating

PCS plaster is versatile, fitting for a wide range of interior walls and ceilings. It can be applied manually or mechanically in one or two layers on various rough and absorbent materials, such as:

  • IsoHemp hemp blocks
  • Concrete and lattice blocks
  • Aerated concrete blocks
  • Terracotta blocks and bricks

Understanding the significance of material selection for building performance, ease of installation, environmental impact, and health, we offer a practical guide to applying PCS natural interior rendering. Additionally, our YouTube channel provides tutorial videos to assist you in using PCS plaster effectively.

For enhancing hempcrete block construction, IsoHemp offers a range of complementary products designed for both indoor and outdoor applications:

Adhesive Mortar: A natural, limestone-based adhesive, specially formulated for hempcrete blocks. It replaces traditional mortar and is applied in a thin, 3 mm joint using a mortar comb or a special trowel.

Lintels: Prefabricated lintels made of hempcrete with a concrete core reinforcement, suitable for door and window openings in hempcrete block masonry. These lintels are designed for new constructions and renovations, available in various widths (9cm to 30cm) and lengths, effectively eliminating thermal bridges and enhancing insulation continuity.

Brackets: Recommended for securing hempcrete blocks above window and door openings when IsoHemp lintels are not used. Ideal for interior renovations where space above the opening is limited. Brackets also serve as connectors between long, thin lintels or for load distribution in certain scenarios.

Angle Bars: Suggested for the first row of hempcrete blocks, particularly in outdoor insulation to replace substructures when there’s no suitable foundation. They can also support suspended hempcrete block masonry in new constructions, acting sometimes as lintels or connectors between two long, thick lintels.


  • Hammer-in Hooks: Galvanized wire pegs (3.5mm thick) recommended for attaching hemp blocks to load-bearing structures like concrete masonry or bricks. The peg is driven into the existing wall and embedded in the masonry joint of the IsoHemp hempcrete blocks.
  • Connector Brackets: These brackets serve as mechanical connectors, linking the hempcrete blocks with the existing structure for both interior and exterior insulation. They attach to the frame and reinforcing beams, ensuring a secure connection.

Each of these products is tailored to optimize the construction and renovation process with hempcrete blocks, providing durable, efficient solutions across a wide range of applications.


Hemp blocks for buildings with load-bearing masonry

Load Bearing Masonry

The traditional system of load-bearing masonry, using materials like concrete blocks and terracotta, is evolving. Advances in product efficiency and glued masonry techniques are enhancing effectiveness. However, for top-tier performance, it still requires supplementary insulation.

Adding hemp blocks to masonry, ideally externally, creates a durable insulating layer that maintains its efficiency without settling or degrading over decades. This method only requires extending the foundation slab and roof to begin the hemp blockwork.

Using hemp blocks offers stable, long-lasting insulation with a natural approach, presenting several benefits in load-bearing masonry:

  • Consistent durability and performance
  • Traditional construction aesthetics
  • Ideal for renders and cladding
  • Simplifies construction to a single masonry trade

Incorporating hemp blocks into load-bearing masonry enables buildings to achieve superior thermal efficiency, easily meeting standards from low-energy to passive house levels.

Hemp blocks for buildings with the Hempro system

Hempro System

The IsoHemp Hempro system eliminates the need for additional insulation, allowing for construction using exclusively hemp blocks. This comprehensive range ensures a uniform building that fully leverages hemp’s benefits.

The Hempro system offers multiple benefits for construction, including a breathable and uniform envelope, high insulation with minimal thickness, quick and traditional installation, and an excellent cost-to-performance ratio. This 100% hemp solution involves two types of 30 cm thick hemp blocks: solid and machined (holed and U-blocks), enhancing the building’s insulation and structural integrity.

Machined blocks provide insulated formwork for reinforced concrete structural frames, with holed blocks for columns and U-blocks for supporting beams. This system is versatile, suitable for anything from single-family homes to eco-neighbourhoods, facilitating the construction of low-energy to passive buildings. The Hempro standard wall uses 30 or 36 cm thick hemp blocks, with the option to add a second layer of hemp block masonry for superior thermal performance.

Building with wood

Timber Construction

Hemp blocks enhance wooden constructions by merging lightness with high thermal inertia, creating an efficient and comfortable building environment. Wooden constructions offer rapid assembly (within 2-3 weeks for the structure), minimised thermal bridging due to wood’s insulating properties, and economic advantages from lighter foundations. However, their lightness can lead to significant temperature fluctuations, impacting energy use and comfort, which makes integrating materials like hemp blocks crucial for balancing thermal inertia without compromising economic benefits.

Hemp blocks fit seamlessly into timber column-beam structures, filling the gaps between columns to form an insulating and cohesive envelope. This combination is ideal for various projects, including industrial, office, and residential buildings, and can incorporate concrete and steel to leverage the strengths of different materials.

Benefits of using hemp blocks with timber column-beam systems include:

  • Sustainable and eco-friendly construction
  • Lightweight yet thermally inert structure
  • Suitable for annexes and DIY projects
  • Ensures a breathable and unified envelope

Employing hemp blocks with timber columns and beams facilitates achieving exceptional energy efficiency, from low-energy to passive building standards, without sacrificing performance.

Building with Column-Beam structures

Column-Beam Structures

Hemp blocks integrate seamlessly with column-beam structures, offering a swift construction process and insulating benefits that ensure significant thermal inertia for the building’s envelope.

Column-beam structures, regardless of being wood, steel, or concrete, facilitate comfortable and energy-efficient buildings. Their advantages include quick assembly, architectural flexibility, and the ability to incorporate wide openings due to large spans.

The IsoHemp Hempro system revolutionizes construction by eliminating the need for any insulation beyond hemp blocks. This system, comprising 30 cm thick solid and machined (holed and U-shaped) hemp blocks, provides a comprehensive solution that encapsulates all the benefits of hemp. Machined blocks act as insulating formwork for structural frames, with specific blocks designed for columns and beams, supporting both floors and roofs. This approach is adaptable from individual homes to eco-neighborhoods, facilitating the construction of buildings ranging from low-energy to passive standards.

The Hempro system offers numerous advantages:

  • A breathable, uniform envelope
  • High insulation with minimal material thickness
  • Speedy and conventional installation
  • An outstanding cost-to-performance ratio

Building with the Hempro system ensures thermal efficiency to meet diverse requirements, with standard walls made from 30 cm or 36 cm thick hemp blocks. For enhanced thermal performance, adding a secondary layer of hemp block masonry is an option, allowing for customized insulation levels.

CLT timber structure


Hemp blocks complement cross-laminated timber (CLT) constructions perfectly, marrying the rapid assembly advantages of solid wood panels with the insulating and protective qualities of hemp. Used in various residential and non-residential projects, CLT enables the swift erection of the building’s shell and structure. Hemp blocks can be utilized as both interior and exterior lining in CLT constructions, allowing the wood to breathe and offering enhanced protection, alongside a broad range of finish options that improve thermal and acoustic comfort.

Benefits of integrating hemp blocks with CLT include:

  • Accelerated construction timelines
  • Significantly enhanced acoustic properties
  • Simplified construction processes
  • Architectural flexibility

Building with CLT and hemp blocks facilitates achieving exceptional thermal performance, enabling the construction of everything from low-energy to passive buildings with ease.

Metal structure

Metal Structures

Hemp blocks are increasingly used with metal structures in a variety of building types, including industrial, apartment, and both single and multi-occupancy dwellings. They create a uniform insulating envelope around the metal frame, incorporating openings for doors and windows. This method results in the construction of high-performance buildings with breathable, insulating, and cohesive envelopes.

The benefits of using hemp blocks with metal structures are notable:

  • Quick construction with precise control over joints and connections
  • Enhanced thermal and acoustic building performance
  • Added fire protection for the metal framework

Constructing with metal structures and hemp blocks enables the attainment of superior energy efficiency, facilitating the easy achievement of standards from low-energy to passive buildings.

Technical Documentation