PRODUCT PROFILE • RWX+

RWX Sandwich Panel

Key Features

Premium RWX (Stone Wool) insulated panels
Outstanding non-combustible performance (Class A1) with heat resistance exceeding 1,000°C
Ideal for electrical rooms, generator rooms, and specialized temperature-controlled environments

FIRE RESISTANCE

Class A1 (Non-Combustible)

SOUND REDUCTION

STC 30+ dB

THICKNESS

50–150 mm

Technical Specifications

Core: High-density Rockwool fiber, 100–120 kg/m³

Thermal: λ = 0.035–0.038 W/m·K

FM Global: Complies with FM 4880 / FM 4881 / FM 4882 standards

Skin: PPGI Steel / SuperDyma Steel / Stainless Steel

RWX
SANDWICH PANEL

What is RWX Sandwich Panel?

RWX Sandwich Panels are fire-rated insulated metal panels featuring a stone wool (mineral wool) core sandwiched between two steel facings. The core is made from molten basalt rock spun into fibers and compressed perpendicular to the steel sheets, creating exceptional fire resistance and acoustic insulation properties that cannot be matched by organic foam cores like PUR or PIR.

Key Features

01

Non-Combustible

Euro Class A1 fire rating – withstands temperatures above 1,000°C without igniting, emitting toxic smoke, or melting.

02

Superior Fire Barrier

Supports designs in compliance with FM 4880/4881/4882 and BS 476 standards (based on certified test reports).

03

Excellent Acoustic
Insulation

Provides excellent sound absorption of 30+ dB (50 mm), making it suitable for generator rooms and industrial facilities requiring noise control.

04

Water-Repellent &
Moisture Resistant

Does not absorb moisture, helps prevent mold growth, resists moisture-related deterioration, and is ideal for Thailand’s hot and humid climate.

05

High-Temperature Stability

Operating temperature range from -30°C to +250°C, with a melting point above 1,000°C and long-term resistance to performance degradation.

06

Long-Term Durability

Service life exceeding 50 years without shrinkage or deterioration over time, and completely asbestos-free for safe use.

Product Specifications

Specification	Detail
Product Name	MKS RW/L-C Fire proof Sandwich Panel, MKS RW/X-C Fire proof
Width	1200 mm Standard
Length	Up to Requirement / Transport / Container
Facer Material	Superdyma CRP Anti-Bacterial ZM180, Stainless Steel AISI304
Facer Thickness	0.45 – 0.65 mm (APT), FM Approved ≥ 0.55mm (APT)
Facer Color	Off White / Up to Requirement
Surface Type	Flat and Rib
Panel Thickness	40, 50, 75, 100, 125, 150 mm
Thermal Conductivity (λ)	0.036 – 0.038 W/mK
Test Method	FM Approved, BS-476

Fire-Rated Walls

2–4 hour fire-rated wall systems for factories, warehouses, and high-rise buildings requiring FM 4880/FM 4881 standards.

Generator / Electrical

Generator rooms, electrical rooms, and switchgear rooms with fire risks and high noise levels, requiring sound insulation performance of 30+ dB.

Cleanroom

Pharmaceutical facilities, food processing plants, and production areas requiring FM4882 certification for smoke-sensitive occupancies.

Industrial Acoustic Wall Systems

Factories with high noise levels (>85 dB) that require noise reduction for employees while maintaining fire protection performance.

Healthcare

Operating rooms, ICUs, and isolation rooms requiring Class A1 non-combustible materials with anti-bacterial coating.

Hazardous Storage

Chemical, oil, and flammable material storage facilities requiring Euro Class A1 non-combustible standards.

FM Standards
Quick Guide

FM4880 = Interior Panels (Interior Walls and Ceilings) – Required for Standard Fire Protection Applications

FM4881 = Exterior Panels (Exterior Walls) – Enhanced Wind Load Performance Testing in Addition to FM4880 Requirements

FM4882 = Cleanroom and Smoke-Sensitive Applications (Pharmaceutical and Food Production Facilities) – Includes FM4880 Requirements, ASTM E84 Compliance, and 16-Foot Parallel Panel Testing

Rockwool vs PIR Comparison Chart

Criteria	Rockwool RW100/RW125	PIR/PIR FM	Winner
Fire Performance	★★★★★ Non-Combustible A1 (>1000°C)	★★★ Combustible B/C (PIR FM: up to B-s1)	Rockwool
Thermal Efficiency (λ)	0.036 – 0.038 W/m·K	0.020 – 0.023 W/m·K	PIR
Acoustic Insulation	★★★★ 30+ dB (50 mm)	★★★ 22 – 26 dB	Rockwool
Weight	Heavier (15 – 29 kg/m²)	Lighter (8 – 15 kg/m²)	PIR
Moisture Resistance	★★★★ Water-repellent	★★★★★ Closed-cell hydrophobic	PIR
Installation	Medium (requires structural support)	Easier (lightweight)	PIR
FM Approval	FM4880, FM4881, FM4882	FM4880, FM4881 (FM grade only)	Both
Cost	Higher initial cost	Moderate (FM grade: premium)	PIR
Lifespan in Fire Zones	50+ years (non-degrading)	20 – 30 years	Rockwool

Choose RWX When:

Fire safety is the top priority

→ Non-Combustible Class A1 is required
The area has a high fire risk

→ Generator rooms, chemical storage facilities, and industrial plants
Excellent sound insulation is required

→ 30+ dB sound reduction
Required by insurance policies

→ Some policies require Class A1 materials
FM4882 Cleanroom applications

→ Pharmaceutical and food processing facilities
Long-term performance is required

→ Service life of 50+ years with minimal deterioration

Choose PIR When:

Energy efficiency is the priority

→ Cold rooms and frozen storage warehouses
Weight limitations are a concern

→ Existing structures and older buildings
Space is limited

→ Thinner wall systems (PIR can be up to 30% thinner)
Budget is limited

→ PIR is generally more cost-effective than RWX
Moderate fire performance is sufficient

→ B-s1 classification is adequate (FM-approved PIR)
Easier installation is preferred

→ Lightweight material requiring less labor

Fire Rating Requirements

Application Type	Fire Rating Required	Recommended Thickness	Notes
Low fire risk areas (พื้นที่เสี่ยงไฟต่ำ)	1–2 hours	50–75 mm	Offices, meeting rooms and general partitions
Generator rooms (ห้องเครื่องปั่นไฟ)	2–3 hours	75–100 mm	Requires acoustic and fire protection
Chemical storage (คลังเคมี)	3–4 hours	100–150 mm	High-hazard area requiring maximum fire protection
Cleanrooms FM4882 (ห้องผลิตยา/อาหาร)	2–3 hours	75–100 mm	Smoke-sensitive area with GMP requirements
Fire escape corridors (ทางหนีไฟ)	2 hours minimum	75–100 mm	Building code compliance required

Acoustic Performance Guide

Panel Thickness	Sound Reduction (dB)	Suitable For
50 mm	30–32 dB	Light noise control and office partitions
75 mm	35–37 dB	Moderate noise and small generator rooms
100 mm	38–40 dB	High-noise factories and large generators (500 kVA+)
125–150 mm	41–43 dB	Extreme noise control, recording studios and hospitals located near generators

Weight Specifications

Thickness (mm)	U-Value RW100 (W/m²·K)	U-Value RW125 (W/m²·K)	R-Value RW100 (m²·K/W)	R-Value RW125 (m²·K/W)
50	0.66	0.68	1.52	1.47
75	0.44	0.45	2.27	2.21
100	0.33	0.34	3.03	2.94
125	0.26	0.27	3.79	3.68
150	0.22	0.23	4.55	4.41

Thermal Performance (U-Value & R-Value)

Thickness (mm)	Weight RW100 (kg/m²)	Weight RW125 (kg/m²)	Structural Consideration
50	15	16	Light – suitable for standard structures
75	18.5	19.5	Medium – standard steel support required
100	22	23.5	Heavy – verify structural capacity
125	25.5	27	Very heavy – reinforced support needed
150	29	31	Maximum – special structural design required

Pricing Factors for
RWX Panels

RWX Sandwich Panel pricing depends on multiple factors, helping ensure more accurate budget planning.

MKS PANEL Certificates

Panel Thickness

50–75 mm: Lowest Cost (Standard)

100 mm: Mid-Range Pricing (Most Popular)

125–150 mm: Highest Cost (+30–50%)

Facer Grade

PPGI Color: Standard Pricing

ZM180 Anti-Bacterial: Premium +10–15%

Stainless Steel AISI304: Premium +40–60%

💡 Cleanroom applications require anti-bacterial coating.

FM Certification Level

FM4880/FM4881: Standard FM Certification

FM4882 Cleanroom: Additional Testing Required (+10–15%)

💡 FM4882 = extra ASTM E84 + 16ft test

Panel Length

Standard Length (3–6 m): Standard Pricing

Long Panels (>8 m): Additional Transportation Cost +5–10%

Custom Cut Lengths: Minimum Order Quantity May Apply

💡 Longer panels reduce joint lines but increase transportation costs.

Order Quantity

Large Project Orders (2,000 m² or More): Project-Based Pricing with Potential Discounts of 10–15%

💡 Minimum order quantities may apply for custom specifications.

Installation & Logistics

Weight: 15–29 kg/m² → structural support

Labor: 15–25% more than PIR

Accessories: Fire-rated sealants +5–8%

💡 The cost of the supporting structure should be included in the project calculation.

Frequently Asked Questions (FAQ)

How is RWX Different from PIR?

RWX is made from Stone Wool (basalt rock), a Euro Class A1 non-combustible material that can withstand temperatures above 1,000°C without igniting or melting, making it ideal for high fire-risk areas. In contrast, PIR is made from Polyisocyanurate foam, an organic material that is combustible (Class B/C or B-s1 for FM-approved PIR), but offers superior thermal insulation performance (λ 0.020–0.023 W/m·K compared to Rockwool’s 0.036–0.038 W/m·K) and lighter weight, making it more suitable for cold rooms and facilities with structural weight limitations.

What Are the Differences Between FM4880, FM4881, and FM4882?

FM4880 is the fundamental standard for interior panels (interior walls and ceilings), requiring successful completion of the corner room fire test and the parallel panel test.

FM4881 is the standard for exterior panels (exterior walls), requiring compliance with all FM4880 test requirements, along with additional wind load and weather resistance testing.

FM4882 is the standard for cleanrooms and smoke-sensitive environments, requiring compliance with FM4880, ASTM E84 (surface burning characteristics), and the 16-foot parallel panel test. It is suitable for pharmaceutical facilities, food processing plants, and semiconductor manufacturing facilities.

How Many Hours of Fire Resistance Can a 100 mm Thick RWX Panel Provide?

A 100 mm thick RWX Panel can generally provide 2–3 hours (120–180 minutes) of fire resistance in accordance with BS 476 or ASTM E119 standards. However, the actual fire resistance rating depends on several factors, including:

The thickness and grade of the facer (steel facing)
The jointing and sealing system
The installation method and supporting structure
The results of the full assembly fire test

For projects requiring a higher level of fire protection, MKS RWX panels with FM Approved certification and full-system fire test reports are recommended.

How Effective Is RWX for Sound Insulation?

RWX provides excellent acoustic insulation due to its fibrous structure, which effectively absorbs sound waves:

50 mm: Sound reduction of approximately 30–32 dB
75 mm: Sound reduction of approximately 35–37 dB
100 mm: Sound reduction of approximately 38–40 dB
125–150 mm: Sound reduction of approximately 41–43 dB

It is ideal for generator rooms, noisy industrial facilities, recording studios, hospitals, and other environments requiring effective noise control, offering superior acoustic performance compared to PIR panels, which typically provide only 22–26 dB of sound reduction.

What RWX Thickness Is Recommended for a Generator Room?

For generator rooms, a RWX panel thickness of 100–125 mm is generally recommended, depending on the following factors:

Generator Capacity:

<250 kVA: 75–100 mm (sound ~35–38 dB)
250–500 kVA: 100 mm (sound ~38–40 dB)
>500 kVA: 125 mm (sound ~41+ dB)

Distance from Occupied Areas:

Adjacent to office areas: 125 mm recommended
More than 20 m away from occupied areas: 75–100 mm is generally sufficient

In addition, fire-rating requirements (typically 2–3 hours) and FM4880 certification requirements should be considered, particularly for insured buildings.

Is RWX Resistant to Moisture?

MKS RWX Sandwich Panels are water-repellent but not completely waterproof.

Suitable for:

High ambient humidity (80–90% RH)
Occasional water splash exposure (with proper sealing)
Thailand’s hot and humid climate

Not Recommended For:

Direct water immersion
Areas with frequent water leakage
Cold rooms with excessive condensation

For high-moisture environments, it is recommended to use stainless steel facings or special anti-corrosion coatings, together with proper joint sealing to ensure long-term performance.

Is RWX Panel Installation Difficult?

RWX panel installation requires more care than PIR installation because:

Challenges:

Heavier weight (15–29 kg/m² compared to 8–15 kg/m² for PIR)
Requires a stronger structural support system
Requires fire-rated sealants at panel joints
Care must be taken to avoid damage or cracking of the panel facer

Recommendations:

Use installers experienced in Rockwool panel installation
Verify the load-bearing structure before installation
Use FM Approved accessories and components
Follow installation procedures in accordance with FM Global standards

MKS provides professional installation teams and on-site supervision to ensure installation quality meets industry standards.

Product Overview

TOPIC	SPECIFICATIONS / DETAILS
Product Name	MKS RW–C Fire proof Sandwich Panel MKS RWX–C Fire proof Sandwich Panel
Standard Width	1,200 mm. (Effective Width)
Length Capacity	Customized per requirement / Optimized for Container Transport
Skin Material (Facer)	Superdyma CRP Anti-Bacterial ZM180 Stainless Steel AISI304 PPGL / PPGI Color Steel
Facer Thickness	0.45 – 0.65 mm. (APT) FM Approved Spec: ≥ 0.55 mm. (APT)
Available Colors	Off White (Standard) / Custom Colors Available
Surface Profiles	Flat (เรียบ) and Rib (ลอน)
Panel Thickness	40 / 50 / 75 / 100 / 125 / 150 mm.
Thermal Conductivity (K)	0.036 – 0.038 W/mK
Certification & Testing	FM Approved (Standard 4880/4881/4882) BS–476 Fire Test Certified

Product Profile

Sandwich Panel Steel Surface

Technical Data

Wind Loading for Open Area or Coast Geography
(Ref. Building Law)

Wind Loading for Open Area or Coast Geography
(Ref. Building Law)

Technical Parameter RW For Sandwich Panel

PROPERTY	RW100	RW125	STANDARD
Compression Strength (kPa)	120	140	EN 826
Density (kg/m³)	100	125	EN 1620
Tensile Strength (kPa)	180	215	EN 1607
Shear Strength (kPa)	47	65	EN 12090
Thermal Conductivity (k) (W/mK)	0.033	0.034–0.038	ASTM C518
Fire Performance	Non-Combustible Euro Class A1	Non-Combustible Euro Class A1	EN 13501-1
Application Temperature Range	–30 °C to 250 °C	–30 °C to 250 °C	ASTM E794
Melting Point of Core	>1,000 °C	>1,000 °C	ASTM C1104
Water Vapor Absorption	<0.04% by vol.	<0.04% by vol.	EN 1609
Water Absorption	<1.0 kg/m²	<1.0 kg/m²	EN 1609

* Thermal conductivity is tested at a mean temperature of 20°C in accordance with ASTM C518 by an externally accredited laboratory. A safety factor of 20% is recommended for design.

** Applications below 0°C are recommended only when the vapor seal on the warm side is adequately installed.

Calculation Proportise

Thickness (mm)	U-Value (W/m²·K)		R-Value (m²·K/W)
Thickness (mm)	RW100	RW125	RW100	RW125
50	0.66	0.68	1.52	1.47
75	0.44	0.45	2.27	2.21
100	0.33	0.34	3.03	2.94
125	0.26	0.27	3.79	3.68
150	0.22	0.23	4.55	4.41

*Note: This table is for reference purposes only. The thermal conductivity (k-value) of RW100 is 0.033 W/m·K, while the thermal conductivity (k-value) of RW125 is 0.034 W/m·K.

Rockwool Sandwich Panel Selection

(Steel Thickness 0.55mm. (TCT))

Thickness (mm)		50	75	100	125	150
Weight (kg/m²)	RW100	15.10	18.20	21.35	24.50	27.60
Weight (kg/m²)	RW125	16.75	19.85	23.00	26.10	29.25
* Estimated weight is calculated based on the standard steel thickness of 0.50/0.50 mm.

* Panel weight (kg/m²) is for reference purposes only.

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