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Damp on bedroom ceiling

Anonymous user 14 May 2019 - 7.49 AM

Damp on bedroom ceiling after loft insulation only on the curved area. How do I insulate the empty cavity. Do I need more ventilation on my roof. Do all roofs need ventilation or do some roofs breathe round the tiles. So I have been told.

5 answers from MyBuilder tradespeople

Best answer
ADR Property Maintenance
Rating: 5 out of 55585 reviews

All roofs need ventilation to stop your timbers rotting,vaulted ceilings will require solid board insulation leaving a 50mm gap between insulation and the felt for air flow. A good loft is a well insulated draughty loft.it stops your heat escaping & keeps your timbers healthy Good luck Alex


14 May 2019


Allaspects joiners, builders and damp specialists
Rating: 4.9 out of 54.95133 reviews
St Helens

If the curved part of the ceiling is on the external wall, it sounds like the insulation installers haven’t pushed the insulation into the eaves. This creates a cold spot on the ceiling, with a black spot mould appearing on the ceiling below


2 June 2019


Energy Ease Ltd
Rating: 5 out of 5552 reviews
Canvey Island

I can understand the view that a good loft is a ventilated one. However; if you insulate between the rafters instead of laying material on the loft floor you won't be separating two environments. Icynene is patented and BBA Certified. The important thing is it has been approved by the Energy Saving Trust to encapsulate the total roof area without the need for a ventilation gap. This is unique, Icynene will let moisture pass through it and leave the building envelope naturally. Although it is already being applied to many new builds the general public and many trades people are unaware of the healthy alternatives on offer.


4 June 2019


Handyman Hero
Rating: 5 out of 55543 reviews
Kingston Upon Thames

The answer offered created more questions and didn't directly answer his question. Answer is. You have to much insulation at the edges of your lift. The exsess insulation has stopped airflow. At the edge of your curved ceiling use a thiner layer of insulation allowing for airflow.


12 June 2019




15 May 2019