Analysis of fireproof performance of light steel structure houses

Light steel structure house realizes excellent fireproof performance through the combination of high-strength steel, fireproof material and intelligent fire protection system, with fire-resistance limit of 1-4 hours, and has the advantages of quick repair and environmental protection. It is necessary to select fireproof coating grade (e.g. H1-H3 grade) and plate thickness (≥12mm) according to specific needs, and check the integrity of fireproof coating regularly.

I. Fireproof Structure Design

Cage-type steel skeleton

The light steel keel is connected by rivets and self-tapping screws to form a cage-type structure, which can maintain overall stability in an earthquake or fire and prevent the floor slab from falling or the wall from collapsing.

Fire partition optimization

Adoption Fire wall and fireproof partition (e.g. calcium silicate board + rock wool filling), together with automatic water spraying system, to retard the spread of fire.

Node protection

Use fireproof coating (fire resistance limit ≥ 1 hour) for key connection parts to prevent loss of strength of steel under high temperature.

II. Fireproof Materials and Parameters

Wall: Calcium silicate board (Class A fireproof) + fiberglass wool filling layer (density ≥80kg/m³) Fire-resistance limit ≥1.5 hours, heat transfer coefficient ≤0.3W/(m²-K)

Roofing: metal engraved sheet + fireproof rock wool (thickness ≥100mm) Fire-resistant limit ≥2 hours, waterproof life ≥30 years

Insulation layer: graphite polystyrene board (B1 level flame retardant) or foam concrete (density ≥500kg/m³) Oxygen index ≥30, does not produce toxic gases in case of fire

III. Advantages of fireproof performance

Fire resistance time

The fire resistance limit of the whole structure reaches 1-4 hours (depending on the thickness of fireproof coating and board), far exceeding the traditional brick structure.

Anti-temperature deformation

Aluminum-zinc plated steel (plating ≥ 80 microns) maintains structural stability at high temperatures of 600°C, delaying collapse for ≥ 30 minutes.

Safety redundancy

The fire prevention system is linked with intelligent fire protection (e.g. smoke alarm + automatic sprinkler), and the escape time window is extended to 15-30 minutes.

IV. Comparison with traditional buildings

Fire-resistant limit: 1.5-4 hours for lightweight steel structure houses (realized through material combination); 0.5-1 hour for traditional brick-concrete structures (relying on solid walls)

Fire Risk: Lightweight steel structure houses have no combustion-aiding materials, which reduces the fire spreading speed by 60%; traditional brick-concrete structures with wooden floor slabs and flammable paints are easy to accelerate the fire.

Environmental protection: Lightweight steel structure housing materials can be recycled, the repair cost after fire is 30% lower; traditional brick-concrete structure has more construction waste and is difficult to repair.

V. Application Cases and Measured Data

Baoding light steel villa: adopting calcium silicate board + fiberglass cotton wall, the measured fire-resistance limit is 2.5 hours, and it passes the grade 9 seismic test.

Steel structure factory building renovation: by adding fireproof partition (fire resistance limit ≥2 hours), fire loss is reduced by 70%.

VI. How to Enhance Fire Resistance of Light Steel Structure House

1. Structural reinforcement and fireproof treatment

Fireproof coating

Thin-coating type (Class B) or thick-coating type (Class H) fireproof coating is adopted and selected according to fire resistance requirements:

Thin-coating type (thickness ≤7mm): applicable to exposed components such as steel beams and columns with fire resistance limit ≤1.5 hours, forming carbonized heat insulation layer by expansion at high temperature.

Thick-coated type (thickness ≥8mm): used for hidden structures with fire resistance limit ≥1.5 hours, directly blocking heat transfer through the thickness of the coating.

Performance parameters: fire-resistant limit up to 1-4 hours, the comprehensive cost as low as 30-80 yuan / square meter.

Outer cladding protection

Cast-in-place concrete/mortar wrapping: Pour concrete or spray mortar (mixed with perlite/asbestos) along the periphery of steel components, fire-resistance limit is increased to 2-3 hours.

Prefabricated fireproof board: use calcium silicate board, rock wool sandwich panel and other dry-hanging wrapping, the construction cycle is shortened by 50%, and the wall verticality error is ≤3‰.

2. Passive fire protection system design

Water cooling method

Circulating water filling in hollow steel components (e.g. steel columns) with rust inhibitor and antifreeze, heat is absorbed through water circulation during fire, slowing down the heating of steel to the critical temperature (≥30 minutes).

Applicable scenes: large-scale factory buildings, high-rise building core support structure.

Shielding and partitioning

Setting Fire-resistant wall/ceiling (e.g. gypsum board + rock wool filling), encasing steel components in fire-resistant materials, fire spreading speed is reduced by 60%.

Adopting fire protection partition design, separating the space through firewalls, with automatic sprinkler system to extend the escape time to 15-30 minutes.

3. Active fire protection system integration

Intelligent fire fighting linkage

Installation of smoke alarm + automatic sprinkler system, triggering water curtain cooling in case of fire, synchronized with the activation of smoke exhaust equipment to reduce the concentration of toxic gases.

Sprinkler water cooling system

Arranging the sprinkler network on the roof, forming a continuous water film at high temperature, controlling the surface temperature of steel below 300℃, and increasing the fire resistance limit by 50%.

Maintenance and Management

Regular inspection: test the integrity of the fireproof coating every 2 years, repair the peeling or cracked parts to ensure that the fire resistance performance is up to standard.

Anti-corrosion and anti-termite: the steel surface needs to be deeply galvanized (coating ≥ 275g/㎡) to prevent corrosion by ant acid and oxidative rust.

Why Choose Us

Shijiazhuang Eiffel Steel Structure Co., Ltd.

Shijiazhuang Eiffel Steel Structure Co., Ltd. is an enterprise dedicated to researching and developing new energy-saving and environmentally friendly houses and construction methods. We always adhere to the values of honesty and quality first, and position ourselves as a leader in high-quality steel structure villa construction. We combine emerging foreign technologies with the actual domestic market and provide customers with one-stop services for prefabricated buildings such as design, production, interior decoration, and whole house customization. The prefabricated buildings produced by the company are widely used in office buildings, villas, rural courtyards, estate clubs, tourist attractions, homestays, hotels, public facilities, etc. 

At present, the company is centered in Shijiazhuang, Hebei Province, with products radiating to regions such as Beijing, Tianjin, Hebei, Shanxi, Shandong, Henan, Liaoning, Mongolia, Jiangsu, Sichuan, and Guangxi, and exported to overseas markets. Adhering to the quality demand of "building a century old villa, choose Eiffel", we strive to create an excellent brand of prefabricated buildings.

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