The most common question from those considering insulation is:
“Which one is cheaper?”
But the right question is actually:
“Which one is more economical in the long run?”
📊 1. Initial Investment Cost (per m²)
| Feature | Spray Polyurethane | Rock Wool |
|---|---|---|
| Average m² price | Medium–High | Medium |
| Labor time | Very fast | Longer |
| Additional material needed | None | Vapor barrier, anchors, cladding |
👉 Rock wool might seem slightly more affordable at first glance.
However, the total system cost needs to be considered.
🏗 2. Thermal Performance (λ Value)
-
Spray polyurethane: 0.022 – 0.028 W/mK
-
Rock wool: 0.035 – 0.040 W/mK
What does this mean?
To provide the same insulation:
-
Rock wool needs to be applied thicker
-
More material = more labor = more cost
💧 3. Water and Moisture Resistance
Rock wool can absorb water.
Its performance decreases if it gets wet.
Spray polyurethane:
-
Seamless
-
Monolithic coating
-
Waterproof structure
This makes a difference, especially for metal roofs and warehouse roofs.
⏳ 4. Application Time
-
100 m² area:
-
Spray polyurethane → 1 day
-
Rock wool → 2–3 days
-
In industrial facilities, time = money.
💰 5. Total Cost over 5 Years
Let's say a 100 m² roof:
-
Rock wool initial investment: X TL
-
Spray polyurethane: X + 10%
However, if the energy saving difference is 15–20% higher,
the difference will be recouped within 2–3 years.
Subsequent years will be pure profit.
🔥 Conclusion: Which is More Economical?
In the short term:
👉 Rock wool might seem slightly cheaper.
In the long term:
👉 Spray polyurethane is more profitable due to lower energy consumption + less maintenance + longer lifespan.
