We live in a modern house (built 2003) with good loft insulation (including loft hatch), the eves vents aren’t blocked and the loft isn’t overcrowded, there are no obvious broken tiles / leaks. There is however a lot of condensation (the boxes of Christmas decorations were a little damp). The internet just tells me the above are the problem, any ideas or recommendations as to how we can deal with it? Thanks
Any bathroom extractors going up there?
My old house had same issue where the builders had gaffer taped some sections of hose badly.
Can you add more ventilation either through eaves/soffit and vents at ridge level to encourage a cross flow of air?
You can also get tile vents and felt lap vents.
I would try that approach first.
Do you have a lot of boxes up there ? This can effect airflow.
Other than that it would involve adding insulation between the rafters .
Would be worth getting good advice from a building surveyor to assess the roof , what you have to make sure you don’t just throw money at it or make the situation worse.
Buy some lap vents, could be a cheap fix.
The trouble with that sort of ventilated loft is the air coming in isn't necessarily dry so you have damp air in a cold space. Our house is the same, 2001, loads of extra insulation, vents are clear, no extractors venting inside, paper and card up there can get damp unless in a sealed box. Maybe invest in some good plastic boxes, the really useful ones for example and some absorbent sachets off EBay to chuck in.
We had this in our current house. The concrete tiles were at the end of their lifespan. Rainy days led to damp under tiles and also the darling board. It looked like condensation, but was basically leaky roof.
New tiles and underlay sorted it.
How often has it been happening? You might have a situation where after a cold spell, warmer, more humid air is entering the lofts through the vents and condensing on the cold boxes. Plastic storage boxes may be the way to go and then keep track of the weather Vs what's happening.
Lap vents are a lot cheaper than a reroof.
Have had a noticeable effect for my roof
And if you aren't happy you can take them out again
Check your loft hatch to see if there's any kind of rubber seal around the edges of the opening. If there isn't anything then look at adding one as that will help to prevent internal moist air from passing up into the loft space.