Hemp Mortar - M5 Class Humidity-Regulating Mortar | Certified NHL 3.5 Hydraulic Lime

M5 certified structural mortar: classification according to UNI EN 998-2 guarantees certified mechanical strength and durability for load-bearing and non-load-bearing masonry

Natural hydraulic lime NHL 3.5: EN 459-1 certified binder, maximum compatibility with natural materials and historic masonry, high breathability and anti-mold alkaline properties

Active moisture regulation: vapor permeability μ < 10 allows masonry to breathe, absorbing and releasing moisture without creating condensation or degradation

Application versatility: ideal for hemp brick laying, historic restoration, traditional masonry repointing, insulation, new constructions and remediation

Hemp Mortar is the versatile solution for:

GREEN BUILDING AND NEW CONSTRUCTIONS
Laying hemp bricks (solid and perforated Canapafor)
Insulating walls with natural blocks
Infill walls for timber, steel, reinforced concrete structures
NZEB, PassivHaus, Class A buildings

HISTORICAL AND CONSERVATIVE RESTORATION
Restoration of ancient walls
Repointing joints of listed buildings
Interventions on historical and monumental buildings
Compatibility with traditional materials (stone, ancient brick, tuff)

REMEDIATION AND DEHUMIDIFICATION
Walls with rising damp problems
Buildings degraded by condensation and mold
Conservative consolidation interventions
Restoration of damaged walls

RENOVATIONS AND EFFICIENCY IMPROVEMENT
Natural internal and external insulation systems
Interventions with Ecobonus and Superbonus
Sustainable energy requalifications
Maximizing ITACA and LEED scores

BAGS FORMAT

25 kg Bags
Standard format for small and medium construction sites, easy to store and transport.

Yield: approximately 12.5-13 kg per sqm per cm of thickness
Ideal for: brick laying, repointing, small repairs

CONSUMPTION AND QUANTITY CALCULATION

For hemp brick laying:

• Recommended joint thickness: 1-1.5 cm
• Average consumption: approximately 25-30 kg per sqm of masonry
• 1 bag (25 kg) = approximately 0.8-1 sqm of masonry

Practical example:
20 sqm wall in 40 cm thick hemp bricks

• Mortar needed: approximately 20-25 bags (500-625 kg)

Contact us for precise calculation based on your project

Email: emporio@canapuglia.it
Phone: +39 080 968 1836
WhatsApp: Chat with us

SEND US:

Estimated quantity (sqm of masonry or number of bags)
Intended application (brick laying, restoration)
Construction site destination

You will receive a dedicated quote within 24 hours with:

Special price for construction site quantities
Precise consumption calculation based on application
Scheduled delivery times
Technical advice on preparation and use

Hemp Mortar works in synergy with:

Solid Hemp Brick - Solid insulating block for infill, M5 mortar ensures certified installation

Canapafor (Hollow Brick) - Interlocking system reduces mortar consumption thanks to the patented geometry

Hemp Base Plaster - Hygro-regulating plaster to equalize the thermal performance of the masonry

Hemp Thermo Plaster - Thermal plaster to optimize final thermal transmittance

Rasante In - Breathable exterior finish to complete the cycle

The Hemp Mortar ensures maximum regulatory compliance:

M5 classification (UNI EN 998-2) - Masonry mortar with certified mechanical resistance

Natural Hydraulic Lime NHL 3.5 (EN 459-1) - Certified binder for maximum compatibility with natural materials

CE marking - European regulatory compliance for masonry mortars

Suitable for CAM - Minimum Environmental Criteria for public procurement (if used with certified CAM hemp bricks)

Restoration compatibility - Suitable for interventions on listed historic buildings

Zero VOC - Natural materials with no harmful emissions

Fire resistance EI 180 - System certified with hemp bricks (12 cm) by Istituto Giordano

What is the difference between Hemp Mortar and traditional cement mortar?

The difference is substantial and concerns compatibility, breathability and durability:

HEMP MORTAR (NHL 3.5 Lime):

• Binder: natural hydraulic lime
• Breathability: high (μ < 10)
• Compatibility: excellent with natural and historic materials
• Strength: M5 (adequate for masonry)
• Behavior: elastic, absorbs micro-movements
• Moisture: moisture regulator, prevents mold
• Sustainability: natural, captures CO₂

TRADITIONAL CEMENT MORTAR:

• Binder: Portland cement
• Breathability: low or none
• Compatibility: problematic with natural materials
• Strength: very high (but excessive for hemp blocks)
• Behavior: rigid, creates tensions and cracks
• Moisture: waterproof, blocks breathability
• Sustainability: high environmental impact

Why NOT use cement mortar with hemp bricks:
Blocks breathability, creates cracks, traps moisture, not compatible with green building certifications.

In summary: Hemp Mortar is the ONLY mortar compatible with hemp building systems and historic masonry.

How to prepare and apply Hemp Mortar?

MIXING PREPARATION:

1. Pour clean water into mixer, concrete mixer or bucket
2. Gradually add Hemp Mortar powder
3. Mix with drill mixer, concrete mixer or mixer
4. Water proportions: 4-5 liters per 25 kg bag (follow instructions on bag)
5. Mix until homogeneous and workable consistency

Correct consistency: mortar soft but not liquid, must hold on trowel without dripping

APPLICATION FOR BRICK LAYING:

1. Slightly moisten bricks before laying
2. Spread mortar on bed joint with trowel
3. Joint thickness: 1-1.5 cm
4. Lay brick and tap lightly
5. Remove excess mortar
6. Technique: staggered joints (running bond)

Work the mixture within 2 hours of preparation. Protect from frost and direct sun during drying.

Need technical support?
Contact us: +39 080 968 1836 or info@canapuglia.it

Is Hemp Mortar suitable for load-bearing masonry?

Yes, with appropriate specifications:

Hemp Mortar is classified M5 according to UNI EN 998-2:

• Compressive strength at 28 days: > 25 N/mmq
• Suitable for load-bearing masonry according to regulations

ATTENTION: Hemp bricks are NOT load-bearing. They are insulating blocks for infill of load-bearing structures (wood, steel, reinforced concrete).

Clarification:

• M5 mortar → can be used for load-bearing masonry
• Hemp bricks → only for infill
• Load-bearing structure is entrusted to frame or reinforced masonry

For traditional load-bearing masonry (stone, brick, tuff): Yes, Hemp Mortar M5 is suitable and particularly recommended for historic restoration.

Can I use Hemp Mortar for plastering?

No, Hemp Mortar is specific for bedding and not for plaster.

HEMP MORTAR (M5 Masonry Mortar):

• Function: brick bedding, joint repointing
• Grain size: coarser
• Application: joints, masonry
• Thickness: 1-1.5 cm (joints)

HEMP PLASTER:

• Function: moisture-regulating plaster for finishes
• Grain size: finer
• Workability: optimized for trowel/float
• Application: scratch coat + body + finish
• Thickness: 1.5-3 cm total

For plastering hemp masonry use hemp plasters available in our catalog.

In summary:

• Hemp Mortar → brick laying
• Hemp Plaster → final plaster

Do you need specific training on hemp bioconstruction? CanaPuglia offers comprehensive training courses for professionals, artisans, and enthusiasts.

BIOCONSTRUCTION COURSE

Renovating and Building with Hemp - Theoretical and practical workshop to learn techniques for laying, design, and site management with natural materials.

PERSONALIZED TECHNICAL CONSULTING

Do you have a specific project? Trust Claudio Natile's experience for dedicated consulting on:

• Optimal material selection
• Quantity calculation and budgeting
• Design support and construction management
• Resolving critical issues on site

Green Building Catalogue 2026 (PDF)