Which building parts are suitable for insulation with rock wool boards?

Rock wool boards are widely used in building insulation projects due to their comprehensive advantages such as fire resistance, heat insulation, sound insulation and weather resistance. The application scenarios and functional focuses of different building parts vary. The following are the main applicable parts and detailed descriptions:

I. Building exterior walls: The core insulation part, taking into account both fire prevention and energy conservation

The exterior wall is the main interface for heat exchange between buildings and the outside world, and it is also the most core application scenario of rock wool boards. It is particularly suitable for external wall insulation systems (EIFS) and internal wall insulation systems. The specific compatibility is as follows:

Functional focus: With "thermal insulation and heat preservation + fire safety" as the core, it also needs to resist the influence of outdoor wind and rain, high and low temperatures and other environmental factors. The A-level non-combustibility and weather resistance (stable from -40℃ to 700℃) of rock wool board can effectively meet the requirements.

Applicable scenarios

New civil buildings, such as high-rise residences, apartments, office buildings, etc., must comply with national building energy-saving standards (such as energy-saving rate ≥65%). Rock wool boards can be fixed on the outside of the wall through "adhesive + anchor fasteners", and then plastering mortar and decorative layers can be applied on the outside. This not only reduces building energy consumption but also avoids cracking and water seepage of the exterior wall.

Energy-saving renovation of old buildings: When upgrading the exterior insulation of old residential areas, the lightweight feature of rock wool boards (with a density of 100-200kg/m³) can avoid increasing the self-weight of the walls, eliminating the need for large-scale structural renovations of buildings. The construction is convenient and does not affect the normal life of residents.

The exterior walls of special places: Hospitals, schools, shopping malls, nursing homes and other densely populated places, due to high fire safety requirements (A-level fireproof materials are needed), rock wool boards are the first choice to replace polystyrene boards (B1 grade) and extruded polystyrene boards (B1 grade), which can reduce the risk of fire.

Note: For rock wool boards used on exterior walls, hydrophobic type (hydrophobic rate ≥98%) should be selected to prevent rainwater from seeping in and causing a decline in insulation performance. The thickness is usually 50 to 100mm, but it needs to be calculated and determined based on the local climate zone (for example, it should be thicker in the severely cold northern regions).

Ii. Building Roofs: Addressing the issue of coordinating insulation and waterproofing

The roof is the "heat barrier" at the top of a building. In summer, it is prone to direct sunlight, causing high indoor temperatures. In winter, it is easy to dissipate heat. Rock wool boards are suitable for both inverted and upright roof insulation structures.

Functional focus: It combines "thermal insulation and heat preservation + compressive strength + anti-aging". The porous structure of rock wool board can block heat transfer, and at the same time, its certain mechanical strength (compressive strength ≥40kPa) can withstand the load of the roof (such as the weight of the waterproof layer and protective layer).

Applicable scenarios

Inverted roof (recommended) : Rock wool boards are laid above the waterproof layer, and a pebble or concrete protective layer is covered on the outside. This can prevent the waterproof layer from aging due to ultraviolet rays and extend the service life of the roof (5-10 years longer than the upright roof). It is suitable for flat roof residences, factories, and large public buildings (such as stadiums).

Upright roof: Rock wool boards are laid between the roof structure layer and the waterproof layer, and a vapor barrier layer (such as polyethylene film) should be added to prevent indoor water vapor from seeping into the rock wool boards and causing them to become damp. This type of roof is suitable for buildings with lower roof load requirements (such as light steel structure roofs).

Note: For roofing rock wool boards, high-density type (density 150-200kg/m³) should be selected to ensure compressive performance. If there is greenery on the roof (such as a roof garden), a drainage layer should be added above the rock wool board to prevent water accumulation.

Iii. Interior Walls and partition walls of buildings: Emphasis is placed on sound insulation and local insulation

Interior walls (such as those in kitchens and bathrooms) and partition walls (walls between adjacent households) have lower requirements for insulation than exterior walls, but they have extremely high demands for sound insulation and noise reduction. Rock wool boards can be used as an integrated material for "insulation + sound insulation"

Functional focus: With "sound insulation as the main and heat preservation as the secondary", the fiber structure of rock wool board can absorb medium and high-frequency noises (such as voices, TV sounds, and water flow sounds from pipes), and the air sound insulation can reach over 40dB, far exceeding that of ordinary brick walls (30-35dB).

Applicable scenarios

Sound insulation layer for partition walls: Rock wool boards (50-80mm thick) are filled in the cavity of the partition wall's keel, and then covered with gypsum boards or calcium silicate boards on the outside. This can effectively block neighborhood noise and enhance the privacy of living, making it suitable for high-rise residences and apartments.

Local insulation of interior walls: For walls in kitchens, bathrooms and other areas with significant temperature differences from the outside, thin rock wool boards (30-50mm thick) can be pasted to reduce heat exchange between the inside and outside (such as avoiding condensation on the wall in winter), and at the same time, hydrophobic rock wool boards can resist water vapor erosion.

Equipment room partition walls: In buildings such as pump rooms, distribution rooms, and elevator machine rooms, the walls need to be treated for sound insulation. Rock wool boards can be used as the core material for sound insulation barriers to reduce the impact of equipment operation noise on the indoor environment.

Iv. Underground parts of Buildings: Addressing the dual demands of dampness and insulation

Underground buildings (such as basements, underground garages, and underground equipment rooms) are susceptible to soil temperature (cold in winter and muggy in summer), and the environment is humid. Rock wool boards are suitable for the exterior walls and top slabs of basements.

Functional focus: Balancing "thermal insulation and heat preservation + moisture-proof and anti-seepage", the hydrophobic rock wool board can prevent moisture from the soil from seeping in, while blocking the heat transfer between the soil and the room, maintaining a constant temperature in the underground space (no less than 10℃ in winter and no more than 26℃ in summer).

Applicable scenarios

Basement exterior wall: Rock wool boards (50-80mm thick) are laid on the outside of the basement exterior wall structural layer, and then waterproof membranes and protective layers are applied on the outside. This can reduce condensation on the basement wall in winter and prevent the wall from getting moldy. It is suitable for basements in residential and commercial complexes.

Basement top slab: If the area above the basement top slab is an outdoor site (such as a community road or green space), rock wool boards can be laid below the top slab, combined with ceiling decoration. This not only provides insulation but also sound insulation, making it suitable for the top slab insulation of underground garages and underground shopping malls.

Note: Rock wool boards used underground must be of high hydrophobic type (hydrophobic rate ≥99%), and they need to be closely attached to the waterproof layer to avoid gaps that may cause water seepage.

V. Special Building Structures: Suitable for irregular shapes and high-temperature scenarios

In addition to the conventional parts, rock wool boards can also be used in the irregular structures and high-temperature environment-related parts of buildings to meet special insulation requirements

1. Curtain wall insulation layer: In the cavity of glass curtain walls or stone curtain walls, rock wool boards (40-60mm thick) can be filled. This not only meets the insulation requirements of the curtain wall system but also avoids the fire hazard of the curtain wall due to its A-level fire resistance. It is suitable for curtain wall projects of high-end public buildings such as office buildings and hotels.

2. Insulation of pipelines and equipment: Local insulation is required for heating pipelines, ventilation pipelines, fire water tanks and other equipment within buildings. Rock wool boards can be cut into arc shapes to wrap around pipelines or made into plate shapes to cover the surface of equipment, reducing heat loss (for example, insulation of heating pipelines can keep the heat loss rate ≤5%), and at the same time, their fire resistance can prevent the spread of fire near the pipelines.

3. Steel structure insulation: For the beams, columns, purlins and other parts of steel structure workshops and steel frame residences, fireproof insulation is required (steel structures tend to soften at high temperatures). Rock wool boards can be made into color steel sandwich panels (with rock wool in the middle and color steel plates on both sides), or separately wrapped around the steel structure, which not only provides insulation but also meets the fire protection time limit requirements (for example, the first-level fire protection time limit ≥1.5 hours).