Installing Rockwool (mineral wool) panels on metal roofs can significantly improve thermal insulation, acoustic performance, and fire resistance. The specific installation method will depend on whether you are using Rockwool sandwich panels (pre-fabricated panels with metal skins and a Rockwool core) or Rockwool insulation boards/batts used in a built-up metal roof system.
Here's a general guide covering both scenarios:
Scenario 1: Installing Rockwool Sandwich Panels on a Metal Roof
Rockwool sandwich panels are composite materials consisting of two metal sheets (steel or aluminum) with a Rockwool core. They are designed for quick and efficient installation.
Materials and Tools You'll Likely Need:
● Rockwool sandwich panels (appropriate size and thickness)
● Metal support profiles (purlins, girts, or sub-structure)
● Self-drilling screws or other suitable fixing screws
● Electric drill/impact driver
● Laser or bubble level
● Measuring tape
● Cutting tools for metal panels (e.g., circular saw with metal blade, nibbler)
● Joint sealant (butyl tape, silicone sealant, or specialized panel sealants)
● Safety equipment: gloves, safety goggles, hard hat, dust mask/respirator, safety shoes.
● Lifting equipment (if panels are large or heavy)
1. Preparation of the Roof Structure:
Ensure the existing metal roof structure (purlins, rafters) is clean, level, and structurally sound.
Verify that the support profiles are properly spaced and aligned according to the panel manufacturer's specifications. This is crucial for proper support and panel alignment.
2. Placement of Metal Profiles (if not already in place):
Install any necessary metal support profiles that will serve as the attachment points for the panels. These create the framework and ensure stability.
3. Alignment of the First Panel:
Carefully position the first Rockwool sandwich panel. This panel sets the alignment for the entire roof.
Use a laser level or a long bubble level to ensure it is perfectly straight and plumb.
Important: Some panels have interlocking systems (tongue and groove) that facilitate alignment and create tight joints. Understand how your specific panels interlock.
4. Fixing the Panels:
Use self-drilling screws (often with sealing washers) to fasten the panel to the metal support profiles.
Follow the manufacturer's instructions precisely for screw type, length, and spacing. Incorrect fastening can compromise the panel's performance, weather-tightness, and structural integrity. Screws typically go through the outer metal skin, the Rockwool core, and into the support structure.
Ensure screws are driven with proper force to avoid crushing the panel or creating depressions, but tight enough for a secure fix.
5. Installation of Additional Panels:
Place subsequent panels, interlocking them tightly with the previously installed ones.
Ensure that the joints are snug to maintain thermal and acoustic performance and prevent water ingress.
For sloping roofs, some manufacturers recommend an overlap configuration for panels in the slope direction, with overlap lengths varying from 50mm to 300mm.
When installing corner panels or around openings, pay attention to aligning them correctly.
6. Joint Sealing (Optional but Recommended for Weather-Tightness):
To enhance airtightness and waterproofing, apply a suitable joint sealant (e.g., butyl sealant tape, silicone sealant) in the joints between panels. This is particularly important in areas exposed to high humidity or wind.
Clean the surface before applying sealant to ensure good adhesion.
7. Flashings and Trims:
Install all necessary flashings, trim pieces, and cappings around the edges of the roof, at ridges, eaves, gables, and penetrations (vents, skylights) to ensure a watertight seal and a finished appearance. These are typically fastened with screws and sealed.
8. Final Review:
Once all panels are installed, thoroughly inspect the entire roof to ensure all panels are firm, level, and properly fastened.
Check all joints and seals for any gaps or imperfections.
Remove any protective films from the panels if required by the manufacturer.
