Defective roofing works causing internal cracks and popping noises

[Sasharoo22]

Hi all

Just after some advice if anyone can help?

We had poor roofing works done last April(ridge/verge/eaves). All perimeter tiles, including the verges and ridge are loose with a large gap in the felt along the ridge - roofing reports and the council have confirmed this. The insulation is stuffed into the eaves and we have failed Part L.

We are now experiencing a regular popping noise early evening to the early morning plus quite bad cracks to the living room ceiling along the plasterboard lines.

I've researched and can anyone tell me if this is correct?

Roof Defects, Thermal Movement, and Ground-Floor Cracking

• Truss Uplift via Microclimate Destabilisation: Displaced ridge and perimeter tiles allow unrestricted external airflow and moisture into the roof cavity. This creates extreme temperature and humidity differentials between the insulated lower chords and exposed upper chords of the fink trusses, accelerating differential thermal expansion and contraction (truss uplift).
• Diurnal Thermal Ratcheting (Acoustic Popping): The unchecked influx of cold night air through the loose ridge and perimeter tiles causes rapid cooling of the roof cavity from early evening to early morning. This triggers a "stick-slip" friction release (the audible popping/ticking noises) at the timber joints and metal gang-nail plates as the fink trusses contract, proving the structure is undergoing active, daily thermal movement.
• Wind Uplift and Structural Stress Transfer: The loose verge and perimeter tiles allow wind to get underneath the roofline, causing cyclic aerodynamic lift and flexing of the gable-end trusses. Because the bedroom ceiling moves dynamically with the roof, it remains intact, while this mechanical and thermal stress is transferred down the rigid gable cavity wall and released into the ground-floor ceiling framework.
• Hygroscopic Movement and Joist Deflection: Rainwater penetrating the compromised gable verge tracks down the inner skin of the brick cavity wall. This moisture accumulates where the first-floor floor joists are pocketed into the gable wall, leading to localised timber expansion, softening, or minor deflection that manifests as plasterboard cracking in both the gable corner and the middle of the living room ceiling span.
  

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• Relevant Industry References:
• Truss Uplift & Popping: BRE Digest 346 ("Pitched Roofs: Performance and Assessment") and NHBC Standards Chapter 7.2. Covers truss movement, stick-slip noise, and microclimate stability.
• Wind Uplift & Stress: British Standard BS 5534 (Code of Practice for Slating and Tiling) and NHBC Clause 7.2.8 (Gable Restraint). Covers structural stress transfer down the gable wall.
• Water Tracking: BRE Good Building Guide 27 ("Building damp-free cavity walls"). Covers roof-to-cavity water entry and intermediate joist deflection.

Any advice or feedback would be appreciated.

Thanks, Sasharoo