Thermal Bridging
A thermal bridge is a localised path where heat bypasses the insulation - through supports, hangers, fasteners, uninsulated valves or gaps in coverage - and escapes much faster than through the insulated surface around it. Thermal bridges can dominate total heat loss even though they cover a small area.
Thermal bridging occurs wherever a conductive element penetrates or interrupts the insulation: pipe supports and shoes, metal fasteners, structural attachments, and - most commonly on industrial plant - bare valves, flanges and instrument connections left uninsulated for access. Because metal conducts heat far better than insulation, these spots run hot and leak disproportionate energy.
On steam and hot-oil systems the uninsulated fittings are frequently the single largest avoidable loss. Closing the bridges - typically with fitted removable covers on the very components that are left bare - captures heat that flat-surface insulation alone misses, and removes the hot, hazardous touch points at the same time.
Related reading
Related terms
Heat Loss · Thermal Insulation · Removable Insulation · U-value (Thermal Transmittance) · Surface Temperature