Façade defects · Insulation
Thermal bridging and missing insulation: causes, risks and repair.
How gaps in insulation and cold bridges cause condensation, mould and heat loss, how a thermographic survey finds them, and how openings confirm what is behind.
| At a glance | |
|---|---|
| What it is | Places where heat escapes through the wall, from missing, slumped or gapped insulation, or from structure bridging it. |
| Main risk | Condensation, mould, heat loss and damage inside the wall. |
| Common on | Older uninsulated walls, and newer walls with poor junction details. |
| Usually spotted by | Residents reporting mould, energy assessments, or a thermographic survey. |
What thermal bridging is
Insulation only works where it is continuous. At slab edges, balcony connections, window reveals and brackets, heat can bypass it. Where insulation is missing, slumped or has gaps, the wall behaves like an uninsulated one in that area.
How to recognise it
- Cold spots on internal walls, ceilings and corners.
- Condensation and black mould in the same places each winter.
- Patchy frost or snow melt on the outside of the wall.
- High heating bills compared with similar flats.
Why it happens
- Insulation omitted, slumped or poorly fitted.
- Uninsulated slab edges and balcony connections.
- Metal brackets passing through the insulation.
- Older walls built before insulation was required.
Why it matters
- Health. Damp and mould affect residents.
- Damage. Condensation inside the wall can decay timber and corrode metal.
- Energy. Heat loss raises bills and affects energy ratings.
How we investigate it
A thermographic survey photographs the façade with a thermal camera when conditions are right: a good temperature difference between inside and outside, no direct sun and a dry façade. The images show where heat is escaping. Targeted openings then confirm what is, or is not, in the wall.
How it is put right
- Fill gaps or replace missing insulation.
- Insulate cavities where suitable.
- Improve details at slab edges and balcony connections.
- Improve ventilation to control condensation.
From our investigations
Examples from our own work. Client and building details are withheld.
See our published case studies
What to send us
The address, where condensation or mould appears, photos, and the building's age. Email enquiries@mtconsult.co.uk, use our contact form or call 0800 048 5229. We typically respond within one working day.
Frequently asked questions
When can a thermal survey be done?
Usually in the colder months, when there is a good temperature difference between inside and out and no direct sun on the façade.
Does a thermal image show what insulation is used?
No. It shows where heat is escaping. Openings confirm what is in the wall.
Is mould always caused by the wall?
Not always. Ventilation and how a flat is used also matter, which the survey considers.
Related
Talk to us
Cold spots and mould?
Our in-house contracting team provides the access and opening-up, so you have one point of contact.