High Strength Fire Mortar - Trade Name: ASTRO HS FM COMPOUND


CE Documents:

'DoP's are Declarators of Performance
'CoC's are 'Certificates of Constancy'

DoP Astro HS FM Compound

CoC Astro HS FM Compound

Astro HS FM Compound

SDS Data

Installation data

Product Images


Astro HS FM Compound is a one-part synthetic mortar used to seal openings in walls and floors to prevent the passage of fire and smoke.

It is mixed with water to produce a trowelable or pourable mortar compound.

The seal created is high strength and non combustible, with a fire resistance to EN 1366-3 2009 at 100mm thickness giving E120 / EI 90 / EI 60: it can be made load bearing.

• Can be reactivated with water to extend the working time.
• Free of halogens, asbestos, fibres & silica and is non toxic.
• Suitable for indoor and outdoor use & can be over painted.
• Not affected by fungus, vermin, rodents and is environmentally friendly.
• Long life and ease of use with minimum waste.
• Acoustic insulation properties

Key Properties

Fire resistance:
120 mins @ 100mm thickness – BS476
EI 60 mins @ 100mm thickness – EN1366-3
E 120 mins I60 mins @ 100mm thickness – EN1366-3

Acoustic Isolation 46dB expected.

Tensile Strength 3N/mm2

Load Bearing - up to 10.29 kN/mm2 (1000mm span)

Can be used in spans up to 2 metres wide.

Can be overpainted.


Certifire 3rd Party Accreditation CF613.


Application and Performance Data

Performance data table.


Intumescent (swells as a result of heat exposure) No
Colour Off-white free flowing powder
BS 476 Fire Resistance 120 min
BS 476 Insulation 120 min
EN 1366-3 Fire Resistance 60 mins
EN 1366-3 Insulation 60 mins
Dry Density 1723 kg/m3
Wet Density 1957 kg/m3
Approvals BS EN
Base Material Synthetic
Mix ratio (mortar to water by weight) 3:1
Can be painted over Yes
Weight 20kg
Shelf Life 12 months (stc)
Expansion on setting 0.08%
Setting Time 20 mins
Packaging Paper valve sack
Compressive strength 3 day - 20 N/mm2
Compressive strength 7 day - 26/Nmm2
Compressive strength 28 day - 30N/mm2
Tensile strength 3N/mm2
Applicatio temperature range 5 to 40C
Temperature resistance - 5 to 100C
Load Bearing Capacity 1000 mm Span - 10.29kN/m2
Load Bearing Capacity 1200 mm Span - 8.57kN/m2
Load Bearing Capacity 1500 mm Span - 6.86kN/m2
Load Bearing Capacity 2000 mm Span 5.15kN/m2
Thermal Conductivity - EN1745 0.57W/mK at 50% / 0.65W/mK at 90%
Yield at 3:1 mortar/water ratio Approx 16L per bag


Astro HS FM Compound is supplied in 20kg bags.




Product Code

Astro HS FM Compound

20kg Bag




To Order & Specify

Please quote - Quantity / Trade Name / Product Ref.
Typical example:-
10 / Astro Astro HS FM Compound/ AFFCHS

Fire Test or Assessment Reports

BS 476 Fire Resistance, 120 min
BS 476 Insulation,120 min
EN 1366-3 Fire Resistance, 60 mins
EN 1366-3 Insulation, 60 minsFire resistance testing to EN


For further information see Installation Sheet.

Health and Safety

See COSHH datasheet for full details.

Environmental Impact

Low VOC (air quality).
No Power Tools required for installation (no energy source required).
Dust free.
Low Ozone Depletion Potential (ODP).
Low Global Warming Potential (GWP).
Smoke and Air Tightness.
Noise Reduction.
Thermal Insulation.
Recycling of Packaging.
Avoidance of Air Filtration.
Manufactured in accordance with ISO 14001.
HS FM is manufactured from recycled components
The life cycle of Astro HS FM Compound is over 20 years.



Astroflame (Fire Seals) Ltd. Intumescent House
Unit 8, The IO Centre, Stephenson Road, Segensworth

tel 0800 023 2482 (01329 844500)

fax 0800 023 2483 (01329 844600)

intl tel +44 1329 844500

intl fax +44 1329 844600