Overview
A composite door should be one of the warmest points in your envelope - U-values as low as 1.0 W/m²K are standard. If yours is letting in cold air, the seal, threshold or compression has failed.
Symptoms
- Cold spots near the door.
- You can feel a draught with the back of your hand.
- Heating bills up.
Common causes
- Failed weather seal.
- Compression cam not adjusted.
- Threshold seal missing or worn.
- Letterplate draught brush missing.
When to call a professional
- Seal or threshold replacement.
Prevention
- Annual seal inspection.