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PIR Pre-insulated (PI) Duct Sheet

PIR Pre-insulated (PI) Duct Sheet, also known as polyisocyanurate pre-insulated duct sheet, is a high-performance insulation material widely used in HVAC (Heating, Ventilation, and Air Conditioning) systems. It is valued for its excellent thermal insulation, durability, and fire resistance, making it a popular alternative to traditional duct materials. Below is a detailed introduction:

Basic Structure

PIR pre-insulated duct sheets consist of three main components:

Core Material: A rigid, closed-cell polyisocyanurate (PIR) foam core. This foam is formed through a chemical reaction between isocyanurate and polyol, creating a dense structure with low thermal conductivity.

Facing Materials: Protective layers bonded to both sides of the PIR core. Common facing materials include:

Aluminum foil or embossed aluminum sheets (for moisture resistance, structural reinforcement, and reflectivity).

Main Properties PIR Pre-insulated (PI) Duct Sheet:

Superior Insulation Performance
PIR foam has extremely low thermal conductivity (typically 0.022W/m·K), comparable to or even better than Phenolic Foam in some formulations. This minimizes heat transfer through the duct, reducing energy loss in HVAC systems and improving overall efficiency.

Excellent Fire Resistance
Unlike some other insulation materials, PIR foam is inherently fire-retardant. It meets strict fire safety standards (e.g., ASTM E84, UL 181) with low flame spread and smoke development. When exposed to high temperatures, it forms a char layer that slows down combustion, making it suitable for buildings with strict fire codes (e.g., hospitals, high-rises).

Durability and Moisture Resistance
The closed-cell structure of PIR foam resists water absorption and moisture penetration, preventing mold growth and maintaining insulation performance over time. This makes it ideal for humid environments (e.g., swimming pools, coastal areas).

Lightweight and Easy to Handle
PIR pre-insulated duct sheets are significantly lighter than traditional metal ducts (e.g., galvanized steel) or duct systems with separate insulation layers. This reduces structural load on buildings (critical for retrofits) and simplifies transportation, handling, and installation.

High Structural Strength
The rigid PIR core, combined with reinforced facing materials, provides good compressive strength and dimensional stability. This allows the ducts to maintain their shape under normal operating conditions, even in unconditioned spaces (e.g., attics, basements).

Hygienic and Low Maintenance
Smooth inner surfaces (often from aluminum facing) minimize dust accumulation, supporting better indoor air quality. This makes PIR ducts suitable for hygiene-sensitive environments such as hospitals, food processing plants, and laboratories. Maintenance requirements are minimal, typically limited to periodic inspections of joints and seals.

certification of PIR Pre-insulated (pI) Duct sheet

Fire Safety, Thermal Conductivity and Physical Performance

BS 476 Part 6&7

ASNZS 1530.3

thermal Conductivity

Compress Strength

CFC HCFC Free

FAQs of PIR Pre-insulated (PI) Duct Sheet

Do PIR pre-insulated (PI) ducts require additional insulation after installation?

No. Unlike traditional steel ducts (which need separate insulation layers like fiberglass), PIR pre-insulated panels are factory-insulated with integrated facing. This eliminates the need for secondary insulation work, saving time and labor.

In which scenarios is PIR pre - insulated duct sheet suitable?

It is widely used in commercial buildings such as offices, shopping malls, and hotels, as well as in residential complexes, industrial facilities, healthcare and food processing facilities, and cold storage and refrigeration systems.

How is PIR pre - insulated duct sheet packaged?

It is usually packaged in plastic film or cartons, with 10 sheets per package.

How to maintain PIR pre-insulated (PI) ducts?

Maintenance is minimal. Regular inspections for joint tightness (to prevent air leakage) and surface damage (e.g., punctures in aluminum facing) are recommended. Cleaning the inner surface periodically (with mild detergents) helps maintain airflow efficiency, especially in hygiene-sensitive areas.