25/03/2026
Small Detail - Big Impact: Why Reveal Insulation Matters
Insulating window and door reveals is one of the most overlooked details in building design, and yet it has a disproportionate impact on performance.
These small junctions around frames are often weak points where insulation is reduced or interrupted. The result?
• Increased heat loss
• Thermal bridging
• Condensation risk
• Reduced occupant comfort
Even in otherwise well-insulated buildings, poorly treated reveals can lead to cold surfaces and localised mould issues. From an energy perspective, they quietly undermine efficiency. From a user perspective, they show up as drafts and cause discomfort.
The solution isn’t complex, but it does require attention to detail:
✔ Maintain continuous insulation around openings
✔ Minimise thermal bridging at junctions
✔ Ensure airtight sealing alongside insulation
✔ Consider reveal design early, not as an afterthought
In high-performance buildings, details matter. And reveals are a perfect example of how small decisions can have a big impact.