Roofing Question

Condesation and dripping in loft space

Hi everyone,
I live in a Victorian terrace and getting condesation on the roof felt which is dripping on the insualtion. I can't see any air bricks or vents. Would the introduction of vents improve the situation? I also have heard of a product called lapvent are these benefical?


2 Answers

Best Answer

Hi Gez
The introduction of ventilation above the insulation level should allow the moist air to escape. You could also increase the thickness of your insulation if possible to 250mm thick . I haven't heard of lapvents but know that tile or slate vents will help . Your local Roofing Supplies should he able to advise you of the quantity needed and a reputable local roofer from this site will be able to supply & fix them for you.

Answered 3rd Dec 2012

Norjan Properties Ltd

Member since 20 Jan 2010


Ensure that the insulation does not go and is not stuffed into the eaves (where the roof meets the ceiling joist) since this restrict the airflow.

Ensure you have a minimum of 250mm of insulation in the loft.

Check that your soffits (if applicable) are vented – if not consider having vents installed.

Try inserting plastic ‘Easyvents’ which open up the gaps in the under tile felt to allow airflow.

Ensure that any belongings do not restrict airflow.



Answered 7th Dec 2012


Member since 26 Jul 2012

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