Problem
Insulation here encroaches on the usable space and causes major disruption to tenants in refurbishment situations.
It does not address cold bridging where floors are supported on the external walls. There is a high risk of condensation at these locations as a result.
The main external envelope ends up considerably colder than before and as a consequence is vulnerable to freeze thaw degradation.
Popular over the years, cavity insulation is limited due to available space.
The external leaf ends up considerably colder than before and therefore vulnerable to freeze thaw degradation.
It does not address cold bridging where floors are supported on the external walls. There is a high risk of condensation at these locations as a result.
Fully filled cavities may provide a bridge that carries moisture between the wet external and dry internal leaves that wets the insulation and turns it, contrary to purpose, into a very effective cold bridge.
Solution
Use external wall insulation (EWI) system
External wall insulation arguably provides the technically best option for upgrading thermal insulation in existing construction and for simplifying new construction.
Weber products
Main products
weber.thermFT
A series of components to provide robust detailing when using External Wall insulation with single skin or frame construction
weber.thermXM
Lightweight external wall insulation incorporating thin coat polymer render and meshcloth reinforcement