"Go with 100 mm — it's the standard" — that's what many contractors say without thinking about Almaty's climate, building orientation, or warehouse purpose. In reality, the choice of sandwich panel thickness affects heating costs throughout the building's entire service life — 20, 30, or 50 years. In Almaty with its −25°C winters, +38°C summers, a 140-day heating season, and intense UV at 700 m elevation, the right choice of thickness represents concrete millions of tenge in savings. Let's break it down in detail.
−25°C
Almaty design winter temperature
the primary parameter for choosing insulation thickness
140 days
Almaty heating season
October–April — one of the key factors for insulation payback calculations
0.26 W/m²·K
U-coefficient for 150 mm panel
thermal transmittance — the lower the value, the better the insulation
3–6 years
improved insulation payback period
difference between 100 mm and 150 mm for warehouses from 2,000 m²
How a Sandwich Panel Is Constructed
A sandwich panel is a three-layer structure:
- Outer steel facing — profiled sheet 0.4–0.7 mm with polymer coating (PE, PUR, PVDF)
- Insulation core — mineral wool (basalt) or polyisocyanurate foam (PIR/PUR)
- Inner steel facing — flat or lightly profiled sheet 0.4–0.5 mm
Panel thickness is essentially the insulation thickness. This determines the thermal transmittance coefficient U (W/m²·K), which defines how much heat the building loses through walls and roof.
Insulation Types: Mineral Wool vs PIR
Mineral wool (basalt fibre):
- λ = 0.036–0.040 W/m·K
- Non-combustible (NG) — mandatory requirement for most warehouses in Kazakhstan
- Good sound absorption
- Slightly heavier than PIR
- More commonly used in Kazakhstan due to price and availability
PIR/PUR (polyisocyanurate / polyurethane foam):
- λ = 0.022–0.026 W/m·K — twice as good as mineral wool
- At equal thickness, PIR is 1.5× warmer than mineral wool
- Combustibility G1–G2 — requires additional fire treatment
- 15–25% more expensive
For most warehouses in Almaty, mineral wool is used — it meets fire safety requirements and provides good insulation at reasonable cost.
Thermal Protection Standards in Almaty
Under SP RK 2.04-107-2013 (Thermal Protection of Buildings) for industrial and warehouse buildings in the Almaty climatic district:
- Minimum wall thermal resistance: R₀ ≥ 1.97 m²·°C/W
- Minimum roof thermal resistance: R₀ ≥ 2.7 m²·°C/W
Which mineral wool panel thickness meets the requirements:
| Panel thickness | R (m²·°C/W) | Standard R | Compliance |
|---|---|---|---|
| 80 mm | 1.95 | 1.97 | ❌ On the borderline |
| 100 mm | 2.44 | 1.97 | ✅ Compliant |
| 120 mm | 2.93 | 1.97 | ✅ Above standard |
| 150 mm | 3.66 | 1.97 | ✅ Significant margin |
| 200 mm | 4.88 | 1.97 | ✅ Maximum insulation |
80 mm in Almaty — Borderline Non-Compliant
Thickness Comparison: Thermal and Financial Performance
Thermal Transmittance by Panel Type
| Thickness | U (W/m²·K), mineral wool | R (m²·°C/W) | U (W/m²·K), PIR |
|---|---|---|---|
| 80 mm | 0.47 | 1.95 | 0.30 |
| 100 mm | 0.38 | 2.44 | 0.24 |
| 120 mm | 0.32 | 2.93 | 0.20 |
| 150 mm | 0.26 | 3.66 | 0.16 |
| 200 mm | 0.20 | 4.88 | 0.12 |
Heat Loss Calculation for a Warehouse in Almaty$2
Input data:
- Warehouse 50×30 m, height 8 m
- Wall area ≈ 1,280 m² (excluding doors), roof area ≈ 1,500 m²
- Design ΔT = +15°C − (−25°C) = 40°C
- Heating period: 140 days × 24 hours = 3,360 hours/year
- Gas tariff: 5,500 ₸/Gcal (boiler efficiency 0.9)
Heat losses through walls and roof using Q = U × S × ΔT × t:
| Thickness | Wall losses (Gcal/year) | Roof losses (Gcal/year) | Total | Gas (₸/year) |
|---|---|---|---|---|
| 80 mm | 208 | 244 | 452 | 2,760,000 |
| 100 mm | 168 | 197 | 365 | 2,228,000 |
| 120 mm | 142 | 166 | 308 | 1,879,000 |
| 150 mm | 115 | 135 | 250 | 1,525,000 |
| 200 mm | 88 | 104 | 192 | 1,171,000 |
Note: simplified calculation, excluding doors, windows and thermal bridges.
Cost and Payback of Different Options for Almaty
For a 50×30 m warehouse (walls 1,280 m², roof 1,500 m²):
| Option | Premium vs 100 mm | Annual gas savings | Payback period |
|---|---|---|---|
| 100 mm | Base | Base | — |
| 120 mm | +1.8–2.5 M ₸ | 349,000 ₸/year | 5–7 years |
| 150 mm | +4.5–6.5 M ₸ | 703,000 ₸/year | 6–9 years |
| 200 mm | +8–11 M ₸ | 1,057,000 ₸/year | 7–10 years |
Panel prices in Almaty 2025–2026: 100 mm ≈ 10,000–13,000 ₸/m², 150 mm ≈ 12,500–16,000 ₸/m², 200 mm ≈ 16,000–21,000 ₸/m².
As Gas Tariffs Rise — Payback Speeds Up
How to Choose Panel Thickness: an Algorithm for Almaty
By Warehouse Purpose
Cold warehouse (unheated):
- Walls and roof: corrugated sheet or thin panels 40–60 mm (only as wind and rain protection)
- Insulation makes no sense — there is no heat source
Unheated warehouse with freeze protection (+5°C):
- Walls: 80–100 mm
- Roof: 100 mm
- Goal — to retain heat from minimal heating (space heaters, standby heating)
Heated warehouse (+10°C … +15°C, heating season):
- Walls in Almaty: 100–120 mm (normative minimum — 100 mm)
- Roof: 120–150 mm (the roof loses more heat due to its horizontal orientation)
- For large warehouses (2,000+ m²) or long-term projects — 150 mm
Comfortable warehouse/manufacturing (+18°C … +22°C, personnel present):
- Walls: 150 mm
- Roof: 150–200 mm
- Rationale: people require a higher temperature, winter indoor-outdoor differential is 40–45°C
Cold storage (+2°C … +8°C):
- Specialised cold storage panels with PIR insulation: 150–200 mm
- Continuous insulation is essential (no thermal bridges); vapour barrier on the warm side
Freezer storage (−18°C … −22°C):
- PIR panels: 200–250 mm, sometimes a double layer
- Special panel joints without thermal bridges
By Location in the Building
| Element | Recommended thickness for Almaty |
|---|---|
| Walls (heated warehouse) | 100–120 mm |
| Roof (heated warehouse) | 120–150 mm |
| End walls (larger area) | 120–150 mm |
| Interior partitions in a heated warehouse | 60–80 mm |
| Cold storage room walls | 150–200 mm PIR |
Almaty's Climate Characteristics and Panel Selection
Summer Overheating: +38°C in the Shade
In July, Almaty air temperatures can reach +38°C, and roof surfaces under direct sunlight can reach +65–75°C. Without insulation, heat radiation from the roof turns a warehouse into an oven. Even 100 mm panels noticeably reduce heat gain in summer.
Conclusion: In Almaty a panel serves a dual function — protecting against heat loss in winter and overheating in summer. This double role makes insulation even more cost-effective.
Condensation: Mountain Humidity
In Almaty, sharp daily temperature swings (up to 20–25°C between night and day in summer) lead to condensation on cold surfaces. Thin panels (80 mm) in Almaty's humidity conditions risk condensation on the inner panel surface.
Dew point rule: The dew point must remain inside the insulation, not on the inner panel surface. For Almaty (60–70% humidity in autumn and spring), R ≥ 2.0 m²·°C/W is required — guaranteed by a 100 mm or thicker panel.
Ultraviolet Radiation: Coating Matters as Much as Thickness
At 700 m elevation, UV radiation is 20–25% more intense than at sea level. Panel coating directly affects service life:
| Coating | Service life in Almaty | Recommendation |
|---|---|---|
| Polyester PE | 5–8 years (fades) | ❌ Not recommended |
| Pural PUR | 15–20 years | ✅ Almaty standard |
| PVDF | 25–35 years | ✅ For long-term projects |
Don't Save on Coating at the Expense of Thickness
Comparison of Panel Manufacturers Available in Almaty
| Manufacturer | Origin | Mineral wool | PIR | Availability |
|---|---|---|---|---|
| Metall Profil | Russia | ✅ | ✅ | Good (supply) |
| NZ Profil | Nur-Sultan (KZ) | ✅ | — | Excellent |
| Alcometal | Almaty region (KZ) | ✅ | — | Good |
| ST-Profil | KZ | ✅ | — | Good |
| Ruukki / Paroc | Finland/Sweden | ✅ | ✅ | On order, longer lead time |
| Isopan | Italy | ✅ | ✅ | On order |
Kazakhstani manufacturers have a logistics and lead-time advantage. Quality is comparable to Russian products with proper production quality control.
Common Mistakes When Choosing Panels for Almaty
Mistake 1: Using the same thickness for walls and roof. The roof in a horizontal position loses more heat (the surface is parallel to the heat flow from below) and bears greater snow load. The roof should always be one or two sizes thicker.
Mistake 2: Ignoring thermal bridges. Doors, columns, window openings — all are cold bridges. Particularly critical are panel-to-foundation joints. Without proper insulation of junctions, even a 150 mm panel will not achieve its calculated efficiency.
Mistake 3: PE coating for the roof in Almaty. The roof receives maximum UV. Polyester fades in 5–7 years, then rusts. Roof panels — PUR or PVDF only.
Mistake 4: Not accounting for snow load when selecting the roof profile. In Almaty — snow zone V–VI (2.5–3.0 kPa). Roof sheet thinner than 0.6 mm — risk of deformation under snow accumulation.
We'll select the right panel thickness and type for your Almaty warehouse
StroyHub engineers carry out thermal calculations for each specific project in Almaty — accounting for climate, intended use, and budget. No one-size-fits-all solutions.
FAQ
What thickness should I choose for a small 500 m² heated warehouse in Almaty$2?
Walls 100 mm (PUR/PVDF), roof 120–150 mm. For a 500 m² warehouse, the premium for 150 mm vs 100 mm is around 1.5–2.5 M ₸. Annual gas savings — 200–280K ₸. Payback within 7–10 years.
Is it worth choosing PIR panels instead of mineral wool for Almaty?
For a standard heated warehouse in Almaty — not necessarily. Mineral wool at 100–150 mm with correct installation meets normative values. PIR makes sense for cold storage (reduced thickness for better insulation) and projects with height restrictions.
Do I need to insulate the floor?
In Almaty for heated warehouses — floor insulation reduces heat losses by 5–10% and eliminates the "cold floor" effect that causes lower-rack temperatures to fall below the norm. Extruded polystyrene (penoplex) 50–80 mm under the concrete slab is a sensible solution within budget.
How do I check panel quality on delivery?
Measure the actual insulation thickness (probe or ultrasonic thickness gauge). Request a certificate of conformity and thermal conductivity test results. Check the labelling — the coating type must match the specification.
