Thermafleece vs. Mineral Fibre: Insulation Comparison
“Mineral fibre” is a general term for common insulation materials like fibreglass and rockwool. While Thermafleece and mineral fibre can be used interchangeably in many building situations, Thermafleece offers several distinct advantages.
The Big Picture: All Insulation Pays for Itself
When comparing upfront costs, remember that all insulation pays for itself over time through energy savings. Although initial prices vary, when viewed over the lifetime of the building, the net cost difference between these insulation types is relatively small.
Key Differences at a Glance
1. Breathability & Moisture Control
- Thermafleece: Truly breathable. It doesn’t just allow vapour to pass through; it actively buffers moisture (absorbing and releasing it), which prevents the buildup of harmful condensation.
- Mineral Fibre: While mineral fibre is “vapour open”, glass and rock fibres cannot buffer moisture. This means fluctuations in humidity within the building structure go completely unchecked.
2. Environmental Impact
- Thermafleece: Features a significantly lower carbon footprint. It requires less energy to manufacture, and the natural wool actively removes and stores carbon as it grows, locking it away for decades.
- Mineral Fibre: Has a higher carbon footprint due to the intensive heat and energy required to melt rock or glass during manufacturing.
3. Air Quality & Health
- Thermafleece: Laboratory tests show exceptionally low chemical emissions. Furthermore, the proteins in wool naturally absorb and destroy harmful substances like formaldehyde. By buffering humidity, it also drastically reduces the risk of mould growth and associated health issues.
- Mineral Fibre: Does not absorb indoor air pollutants or buffer humidity.
4. Acoustic Performance (Soundproofing)
- Thermafleece & Mineral Fibre: Both are excellent at absorbing sound. Just 50mm of Thermafleece can significantly reduce noise reverberation within building voids, performing at a similar level to specialist acoustic mineral fibre.
