Fondo Pozzolanico MGN

The MGN Lime Tanking Slurry System

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Fondo Pozzolanico MGN - Description

The MGN Lime-Pozzolanic Tanking Slurry System consists of two products, that must be used together:

The FONDO POZZOLANICO MGN base coat: a powder; a special fine-granulation lime base coat in powder form.
The FISSATIVO P1 MGN liquid binder: a liquid that is mixed with the powder. The liquid binder gives the slurry high mechanical resistance in a thin form factor, making it withstand liquid water, hygrostatic pressure, mechanical wear-and-tear and bad weather. It also significantly improves the adherence of the product, making the lime tanking slurry adhere extremely well to poorly-absorbent or completely non-absorbent surfaces (e.g. concrete, tiles, metals, plastics etc. virtually anything).

Both products are vapour-permeable and do not contain any harmful substances.

When the two materials are mixed together, they form a high-adherence lime tanking slurry, which in a slim coat is suitable for difficult, hard-to-resolve waterproofing cases, such as the:

Waterproofing of any horizontal or vertical surface
Waterproofing “leaky” floors or floors damaged by salts
Waterproofing of non-absorbent or poorly absorbent surfaces (old abnormal house floors, tiles with joints, metal and plastic surfaces etc.)
Waterproofing of areas with significant sideways or hydrostatic pressure where the application of a thicker waterproofing or tanking system, due to space constraints, is not possible (e.g. shower floors, uneven concrete floors)
Filling and waterproofing of leaky reinforced concrete joints in cases of suspected humidity
Levelling and waterproofing of older surfaces, often laid at different times and consisting of different materials
A waterproofing coat near the base of an old masonry, to protect the lime plastering from the effect of dampness and salts from the ground (e.g. from wall bases, floor slabs, pavements etc.).
In new constructions, for any type of restoration, renovation, redevelopment; for buildings with special uses

Once set, it provides durable, heavy-duty, long-lasting waterproofing, as it is free of salts, and it is also salt-resistant.

Recommended application thickness of the tanking slurry is 3-5 mm. A fibreglass mesh must always be used and embedded into the tanking slurry.

The Fissativo P1 MGN liquid binder is a ready to use product. It must be used undiluted without adding any water to the mix. A 25 kg Fondo Pozzolanico bag needs approximately 10 litres of P1 liquid binder.

Key Features

Here are some key features of this product.

Breathable

Being a lime plaster, it's naturally vapour permeable or breathable.

Waterproof

Once set, it becomes waterproof, resisting significant sideways pressure. blocking any liquid water ingress.

Resistant to All Salts

This lime plaster is resistant to all types of salts (chlorites, nitrates, sulphates) and acids.

Resistant to High Humidity

This lime plaster can tolerate high levels of msoiture and humidity.

No Cement. No Chemicals

This plaster does not contain chemicals or cement - it only contains natural materials.

Extremely Long Lasting

Due to its microporous structure it blocks the movement of salts, being impervious to salts crystallization, crumbling and breakdown.

Versatile

It has multiple uses: It can be used as a plaster, as a render, in basements or in lime floors - anywhere where water and salts are present and a long service life is required.

Suitable for Listed buildings

This plaster is suitable for historic or listed buildings and heritage renovations.

For Cellars, Basements

Can resist high humidity, suitable for cellars, basements.

Composition

Natural air lime: highest purity lime containing min 90% CaO, classified as CL90S according to EN-459-1 standard

Natural pozzolans: volcanic sands and ashes of exclusively natural origin, certified according to EN 197-1 standard

Natural hydraulic lime NHL 5, certified according to EN-459-1 standard

Natural river sands: washed river sands, free of salts and impurities, certified according to EN 13139 standard

Marble powders, certified according to EN 12620 standard

Natural earth pigments for colouring. Highly resistant to UV and sunlight. Won’t fade or discolour.

Natural casein-based resin

Specifications

Granulation (mm)

0-1

Vapour diffusion resistance (μ)

Declared thermal conductivity - λ (D)

0.67

Water absorption

10.5

Adhesion (N / mm²)

1.2

Compressive strength (N / mm²)

CS II

Bulk density (kg / m³)

1650

Bag weight (kg)

Water intake (litre / bag)

None

Consumption (kg / m² / cm)

Application temperature (°C)

5-30

Chloride content (%)

None

Harmful substances

None

Colour

Brown

Certifications

UNI EN 998-1:2016 – Certified General Purpose Plaster for Internal / External Use (GP)

Minimum Environmental Criteria (CAM) Declaration: a “green purchase” environmental declaration, indicating that this product satisfies the environmental requirements of the Italian Government, representing the best ecological solution for a project when taking into account the entire life cycle of a product from manufacturing to disposal.

Free of Harmful Substances including formaldehyde

CE Marking: this product complies with all relevant European Union regulations, meeting all performance requirements required by the CE marking.

Completed Projects

Here are some of our projects using this plaster:

coreconservation banners basement banner4195

Crypt Waterproofing Project

Roman Lime Waterproofing System

Commercial

Solutions

This material can be used in the following applications or solutions:

Waterproofing Basements, Cellars

The Roman Lime Waterproofing System

Photo Galleries

Here are some photos demonstrating this solution. Click on any image to open the photo gallery.

The Crypt Waterproofing Project

Waterproofing the service area of an old crypt with traditional Roman lime waterproofing and Cocciopesto plasters. On some parts of the room the MGN Lime-Pozzolanic Tanking Slurry System has also been applied to reinforce the waterproofing in critical areas.

Videos

Here are some videos related to this solution. Please unmute the videos when playing them.

The Crypt Waterproofing Project

Solutions

Fondo Pozzolanico MGN – Lime Waterproofing Tanking Slurry System Application Tutorial

Plasters

Fondo Pozzolanico MGN – Traditional lime waterproofing system

Plasters

Similar Products

Here are some other similar products of the same category (e.g. other main coats or finishes). Depending on your application, you could use these as alternative products.

Rinzaffo

Roman Waterproofing Lime Base Coat

Base

Waterproofing

Application

Here are some key technical points about how to apply this material correctly:

Waterproofing

Clean the masonry: the plaster must be applied on a cleaned and uniformly wet substrate. All crumbling and loose parts must be removed by brushing so the masonry is free of dust, salts and oils. If possible, also wash the walls with a pressure washer; this will clean and wet the walls in one go. Close larger holes with lime mortar and pieces of bricks.

No salt-inhibitors nor PVA bonding agents should be used before the application of the plaster. The plaster bonds well on its own.

Masonry paints should be removed (which occasionally can be challenging) so the plaster can firmly adhere to the underlying stones or bricks. Remove at least 50% of the existing paint – the more is removed, the better.

Mix the Fondo Pozzolanico powder with the Fissativo P1 liquid binder only. Do NOT add any water to the mix, use the supplied P1 binder only. The mixing can be done manually or with a plastering machine until a homogeneous plaster or slurry is obtained.

Wet the wall fabric abundantly before applying the plaster, as well as in-between each subsequent coat. Lime plasters need moisture as they set slowly in a damp environment. If the walls are already damp, there is no need to wait to become drier, you can proceed with the application of this plaster.

Apply the FONDO POZZOLANICO MGN lime tanking slurry in a thickness never less than 3 mm. Always embed a fine fibreglass mesh (3 x 4 mm) into the material.

IMPORTANT: Close all pores, no matter how small. Treat and apply the plaster as a tanking-grade material. Attention should be paid to compact it on the wall closing off all pores, no matter how small, leaving no gaps or holes where salts or liquid water could come through. Once an area has been completed, recheck that here are no missed holes, not even small ones.
The plaster application video below explains the concept in detail.

Light key: give the plaster a light key using a wet brush. Do not cut into the material with the edge of a trowel.

IMPORTANT: Dark patches. Allow the plaster to dry for 48 hours. Ideally, the whole surface should dry out uniformly to light brown, however you might notice some dark or damp-looking areas exhibiting surface condensation. Dark areas indicate insufficient thickness of the plaster in raport to the amount of moisture behind it. This occurs in areas where the underlying wall fabric is very damp, the intense evaporation causing surface condensation.
The fix is easy: apply extra material over such dark areas increasing the thickness of the plaster, closing off all pores. The increased plaster volume dilutes the vapour flow allowing the surface to dry.

Clean it off all your tools straight away (within 30 minutes after application), otherwise the material becomes non-removable.

Application conditions: ambient and wall temperatures must be between +5 to +30°C during application. Surfaces should be protected from rain and humidity until they have completely dried (approx. 3 – 10 days depending on weather conditions).