Fire Resistant Mortar Installation Guide

 

The Intuchem FR Mortar is an anhydrite calcium sulphate based premixed dry blend and consists of inorganic inert fillers and foamed Perlite. When mixed with water, this produces a trowelable or an easy to pour grade suitable for fire barrier seals through openings in floors and walls.

Intuchem FR Mortar is totally non-combustible to BS 476 Part 4 and EN1366-3. It can be easily designed to provide

a) Non-Load Bearing Seals with up to 4 hrs fire resistance

b) Load Bearing Seals with up to 4 hrs fire resistance

Intuchem FR Mortar expands during cure creating an excellent seal around the service and a strong bond to the surrounding masonry. Intuchem FR Mortar contains no fibers, halogens, solvents, silicone or free added silica.

A unique feature of the Intuchem FR Mortar is that it can be re-activated for up to 2 hours by re-mixing with small quantities of water if necessary every 30 minutes, so eliminating potential waste.

If a NON-LOAD BEARING SEAL is installed in a floor opening, an adequate warning notice or protective covering must be provided to prevent damage to the seal, and possible personnel injury.

If a MAINTENANCE ONLY LOAD BEARING SEAL is installed in a floor opening, an adequate warning notice or protective covering must be provided to prevent damage to the seal and possible personnel injury especially during first 48 hours of drying.

Once the seal is suitably dry, the maximum load bearing capability of the seal is limited to 1.5kn/sq.m - which is considered adequate for most maintenance access purposes.

Also, there should be a warning sign to avoid any point loading on the seal unless the load is spread over an area of minimum 0.09m2.

Intuchem FR Mortar is suitable for sealing openings in walls or floor slabs made from various substrates, most commonly brick, blockwork and concrete.

Technical Specification

An anhydrite calcium sulphate based one part mortar available in dry bags, which is noncombustible and designed to provide load bearing or non-load bearing fire barriers.

Density: Typically 1000 -1300kg/cu.m. (dry, when fully cured).

Mean Flexural Strength: 0.59 N/mm2

Compression Strength: 2.4 N/mm2

Shear Strength : 1.0 N/ mm2

Impact Strength: 5.0 N/ mm2

Thermal Conductivity: 0.289 9 + 3%mcw/m K

Fire Resistance: Up to 240 Minutes Integrity & Insulation

Non-combustibility: Non Combustible – BS476 Part 4

Vapour Resistivity: Nominal 500MNs/g.m.

Setting Time: 45-60 Minutes.

Storage: Ideally between 5º & 35º Celsius. Six months shelf life provided bags are sealed and stored in dry, well-ventilated conditions.

Installation

Intuchem FR Mortar can be simply installed using the following tools and equipment:-

Mixing Container

Power Assisted Stirrer

Suitable Litre Measure

Steel Tape Measure

Hack-Saw

All purpose Saw

Plastic Sheeting

Power Drill

Drill Bit (Various Sizes)

Expanding Steel Anchors

Pointing Knife/Pallet Knife or Similar

Float

Dust Pan and Brush

10mm Diameter Steel Rods

30mm x 30mm x 3mm Steel Angle or Similar

Ensure that all services are complete and installed to the satisfaction of the main contractors representative, and in accordance with the recommendations of the relevant manufacturer or supplier.

Remove all unnecessary combustible materials from the aperture.

Using brush and dustpan, sweep all loose materials from the inner surface of the aperture and surrounding area local to the installation.

 

 

 

Place plastic sheet beneath the working area to catch any falling materials.

Remove any insulation or lagging on ducts or pipes in order to ensure a good seal with the Intuchem FR Mortar and moisten porous slab or wall or wall edges prior to installation.

Waste Disposal - observe recommendations on Health and Safety data sheets in this manual.

The essential material required for the installation of Intuchem FR Mortar in accordance with the Building Regulations 1991 are detailed below.

Depending of the seal configuration, the period of fire resistance required, the aperture dimensions, and any load bearing requirement (maximum 1.5 KN / Sq.Mtr), then reinforcing materials may need to be installed. The positioning of any reinforcement must beat the mid-point of the seal.

The recommended method of providing reinforcement is by installing 10mm diameter mild steel round bar spanning the shortest distance of the aperture, supported on 30mmx30mmx3mm mild steel angle at either 400mm or 600mm centres (see table below)

Typical reinforcement requirements for non-load bearing and load bearing seals are given in tables 1 and 2 below.

 

Table 1 Non Load Bearing Seals

Width of Opening	Length of Opening	Reinforcement Required
Up to 1000mm	Up to 1000mm	NONE
Up to 1000mm	1000mm +	NONE
Up to 1500mm	1000mm+	NONE

 

 

 

 

Table 2 Load Bearing Seals (Maximum 1.5 KN/Sq.Mtr)

		Reinforcement Bar Spacing	Reinforcement Bar Spacing
Width of Opening	Length of Opening	55MM Mortar Thickness	75MM Mortar Thickness
Up to 1000mm	Up to 1000mm	NONE	NONE
Up to 500mm	1000mm – 2000mm +	600mm centres	NONE
500mm – 1000mm	1000mm – 1500mm	400mm centres	NONE
500mm – 1000mm	1500mm – 2000mm +	400mm centres	400mm centres

 

 

For openings with different dimensional characteristics, then please consult Intuchem,

PERIMETER ANGLES
2 No. 30mmx30mmx3mm thick mild steel angles should be positioned within the mid third of the thickness of the seal, each being fixed to opposite sides along the full length of the aperture using noncombustible expanding anchors, or similar.

It is recommended that 8mm x 75mm long rawl bolts or similar are used for expanding anchors.

10MM ROUND BAR
The 10mm Round Bar mild steel rod reinforcement must be individually positioned so as to span the width of the aperture (the shortest dimension) at either 600mm or 400mm centres along the full length of the seal, (subject to the position of any services passing through the aperture). As an alternative, suitable reinforcing mesh can be used in place of the round bar.

ALLOWANCE FOR THERMAL EXPANSION
An allowance for expansion of the steel reinforcement must be provided so that they do not bow and / or distort in a fire situation causing possible damage to the Intuchem FR Mortar Seal.

This allowance must be at least 0.5% of the length of reinforcement (5mm per metre length).

 

SHUTTERING
Depending on the fire rating required, fix suitable shuttering so that the required seal thickness can be achieved. Typical materials used for this purpose include mineral fiber board, timber, expanded metal such as Expamet, polystyrene etc. However, combustible material should be removed a minimum of 48 hours after the completion of the seal.

If access is limited to the top of the floor only, shuttering should be installed first with noncombustible materials and then the reinforcement installed if necessary.

Openings in walls require shuttering on both sides with a small gap/hole left for filling with compound.

Once the shuttering and fixing of reinforcement if any are complete, the opening is ready for filling with the Intuchem FR Mortar.

MIXING AND FILLING
Based on the recommendations add the required amount of mortar to water and mix to a smooth consistency using a power stirrer.

It is necessary to mix a trowelable consistency initially and fill manually around penetrations and small voids. Once the small holes are sealed, finish the opening to the required thickness by pouring the mortar.

Finally, smooth surface using a float if necessary.

When shuttering is removed, fill any gaps left using a trowelable grade of mortar to complete installation.

Apply a suitable warning label and barrier covers to prevent accidental damage to seal or possible personnel injury.

GUIDE TO MIXING
The following mixing ratios are approximate only. Actual quantities required to achieve appropriate consistencies will be determined by environmental and prevailing site conditions.

Coverage	Dry Mortar to Water	55mm seal	75mm seal
For pourable grade	2:1	61 kg per m2	83 kg per m2
For trowelable grade	3:1	63 kg per m2	85 kg per m2

The information in this publication is accurate to the best of the knowledge of Intuchem Ltd.

LEGAL:
As part of our policy of ongoing improvements, we reserve the right to modify, alter or change product specifications without giving notice. Product illustrations are representations only. All information contained in this document is provided for guidance only, and as Intuchem Ltd has no control over the installation methods of the products, or of the prevailing site conditions, no warranties expressed or implied are intended to be given as to the actual performance of the products mentioned or referred to, and no liability whatsoever will be accepted for any loss, damage or injury arising from the use of the information given of products mentioned or referred to herein.