How to choose sandwich panels and insulation: a simple guide without common mistakes

1. Where to start: 4 questions that decide everything

Before ordering, answer four questions — they immediately narrow down options and save money:

• What is the building for? Warehouse, workshop, car wash, retail pavilion, cold room, office.

• What temperature regime do you need? “Just not cold,” stable +18…+22, or even below zero?

• Any fire-safety requirements? Especially important for workshops, warehouses, and buildings with people inside.

• What are the outdoor conditions? Wind, humidity, proximity to water, chemicals/vapors, dust, frequent temperature swings.

Once this is clear, you can correctly choose the panel type, insulation, thickness, and metal coating.

2. Wall vs. roof panels: what’s the difference

• Wall panels are for façades and internal partitions. Key points: appearance, airtight joints, thermal insulation, coating durability.

• Roof panels are for the roof. Critical factors: stiffness, correct profile, water drainage, lock tightness, and installation quality (otherwise you’ll get leaks).

Tip: if you build turnkey, agree on junction details, flashings, ridge, valleys, drip edges early — they affect lifespan as much as the panel itself.

3. Panel thickness: don’t overpay and don’t freeze

Thickness depends on the indoor temperature you want to maintain and how harsh the climate is.

• 50–80 mm — light-use spaces, small pavilions, no strict thermal requirements.

• 100 mm — a universal choice for many warehouses and workshops.

• 120–150 mm — warmer and more stable conditions (office zones, continuous work areas).

• 150–200 mm+ — cold/freezer rooms and buildings with large temperature differences.

Important: thickness alone won’t help if joints and sealing are weak. Heat often escapes through seams, junctions, gates, and windows.

4. Insulation types in sandwich panels: what to choose

EPS (expanded polystyrene)
Pros: usually the most affordable; lightweight; good insulation for standard tasks.
Cons: weaker in fire performance vs. mineral wool; not ideal for high temperatures or specific conditions.
Best for: warehouses and pavilions without strict fire requirements.

Mineral wool (basalt/stone wool)
Pros: high fire safety; good sound insulation; stable at high temperatures.
Cons: heavier; requires quality installation and moisture protection (proper sealing).
Best for: workshops, public buildings, projects with fire and acoustic requirements.

PIR (polyisocyanurate)
Pros: very high insulation with less thickness; great for energy savings; common in energy-efficient and cold-room solutions.
Cons: more expensive than EPS; choose a manufacturer with clear specs and stable quality.
Best for: offices, warm buildings, energy-efficient projects, cold rooms.

5. What to check in panel specs (checklist)

• insulation type and suitability for your project;

• panel thickness (walls and roof may differ);

• metal thickness (stiffness and façade waviness);

• metal coating (UV/corrosion resistance — crucial outdoors);

• lock/profile quality (reduces heat loss and drafts);

• flashings and trims (corners, drip edges, ridge, cover strips);

• installation quality (jointing, fasteners, sealants, vapor/waterproofing at junctions).

6. Common selection mistakes

• copying a neighbor’s insulation without considering fire requirements;

• buying thicker panels but saving on sealing — still cold;

• using the wrong roof panel/profile — leaks later;

• ignoring junction details (gates, windows, corners, roof-to-wall);

• looking only at price per m² and forgetting trims and installation.

7. Quick recommendations

• Budget-friendly and warm for a standard warehouse/pavilion: EPS, often 80–100 mm.

• Fire safety matters: mineral wool + quality sealing.

• Maximum warmth and heating savings: PIR, especially for energy-efficient projects.

• Roofing: always roof panels + proper trims and installation — otherwise repairs will cost more.

Conclusion

The right sandwich panel is the right combination of insulation, thickness, metal, lock design, and professional installation. Chosen properly, you get a fast-built building that looks neat and truly saves on heating.

If you want — tell me the building type (warehouse/workshop/pavilion), size, and required indoor temperature, and I’ll suggest an optimal setup: insulation + thickness + wall/roof panel selection.