Astroflame Passive Fire Protection Products

Trade Name: Astro HS FM Compound

High Strength Fire Mortar

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.


High Strength Fire Mortar at Astroflame.

View a range of styles

>> See more : Additional product images

>> Call us to order: 01329 844 500

>> Email us to order:

DescriptionCE Marking for HS FM Compound.

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



CE InformationCE Marked Documents
'DoP's are 'Declaration of Performance'
'CoC's are 'Certificate of Constancy of Performance'
'TDS' are 'Technical Data Sheet'

Application and Performance Data


Off white free flowing powder


1723 kg/m3 Dry / 1957 kg/m3 Wet

Fire Resistance - BS 467

120 mins @100mm thickness - BS476
EI 60 mins @100mm thickness - EN1366-3

Non combustibility

in accordance with BS 476 part 4

Maximum Opening Span

2 meters

Load Bearing Span

1000mm Span - 10.29kN/mm2
1200mm Span - .57kN/mm2
1500mm Span - .86kN/mm2
2000mm Span - 5.15kN/mm2

Tensile Strength

3 N/mm2

Compressive Strength

20 N/mm2 @ 3 days
26 N/mm2 @ 7 days
30 N/mm2 @ 28 days

Thermal Conductivity

0.57 W/mK @ 50% - EN1745

Sound Reduction

46 dB reduction at 100mm (EXPECTED)

Properties & Specification

Intumescent (swells as a result of heat exposure)



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



Base Material


Can be painted over




Shelf Life

12 months (stc)

Expansion on setting


Setting Time

20 mins


Paper valve sack

Compressive strength

3 day - 20 N/mm2

Compressive strength

7 day - 26/Nmm2

Compressive strength

28 day - 30N/mm2

Tensile strength


Applicatio temperature range

5 to 40?C

Temperature resistance

- 5 to 100?C

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

Product Description




Astro HS FM Compound


20kg Bag

To Order & Specify

Please contact us and quote the following information - Quantity / Product Code / Product Description / Weight> Typical wording - 10 / Astro Astro HS FM Compound/ AFFCHS

>> Tel: 01329 844 500 or >> Email:

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 on installation requirements please review the installation sheet or contact the technical team on: tel 01329 844 500 or email

Health and Safety

The product does not present any known health hazards during or after installation. Normal good industrial and personal hygiene practices should be observed. For further information on health and safety requirements please contact the technical team on: tel 01329 844 500 or email

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)
tel +44 1329 844500
fax +44 1329 844600



Email Astroflame