Loft Space Damp - normal?

scottishminnie

This may seem like a really stupid question (hubby certainly thinks I'm being thick) however it's bothering me so I'll apologise and ask anyway.....

I recently ventured up into the loft to retrieve some empty boxes to store a few items in. They were the original boxes the goods came in. When I lifted them they were cold, which I expected but also felt damp and on closer inspection they had black spots on the outside of the boxes which I take to be mould.

I'm really concerned about this as we store tons of stuff up there, including some fairly expensive paintings and a few antique lamps.

Hubby was dismissive to say the least. He thinks damp is to be expected as there is no heating in the loft and there are "air vents" to the outside where the roof joins (I've no idea if that makes sense to anyone else:o).

Is this normal? It's not an old house (15 years old) and was built by us so we know there have been no damp/leakage issues at all.

macman

It sounds like the ventilation is inadequate. You might need to install some additional soffit ventilators.
Mould has nothing to do with an absence of heating.
Keeping expensive paintings in a loft is a crazy idea anyway, they'll freeze in winter and bake in summer-the compete opposite of what they need (a steady controlled temp).

googler

You don't need to ask us if it 'makes sense' that your husband says there's air vents - go outside, look up at where the roof meets the wall at your guttering and you should be able to see them. Go up there on a windy day and the airflow will be readily apparent.

Again, look at the situation in your loft - is there insulation on the loft floor, above the upper floor ceiling? If so, that's designed to keep your heat in the upper floor, not in the loft.

And, as the previous poster said; your loft will be cold in winter, hot in summer. There's no heating up there, the insulation is designed to isolate the loft from the rest of the house, and ..... get the drift?

scottishminnie

macman wrote: »

Keeping expensive paintings in a loft is a crazy idea anyway, they'll freeze in winter and bake in summer-the compete opposite of what they need (a steady controlled temp).

I know it's not the best place for them however I don't have anywhere else to put them right now and can't sell them at the moment. I have them wrapped in bubble wrap then covered with blankets to minimise any damage.

googler wrote: »

You don't need to ask us if it 'makes sense' that your husband says there's air vents - go outside, look up at where the roof meets the wall at your guttering and you should be able to see them.
Again, look at the situation in your loft - is there insulation on the loft floor, above the upper floor ceiling? If so, that's designed to keep your heat in the upper floor, not in the loft.

I know the air vents are there, I'm not questioning him on that and I do understand that the insulation is designed to keep the house rather than the loft warm.Knowing that it will be cold in winter, hot in summe,r my query was around how damp (as opposed to cold) it should/shouldn't be.

The empty boxes were fairly close to the edge of the roof so I have moved them more to the centre of the loft in case that helps.

If it's not a problem then so be it. It was a genuine question in case hubby was being dismissive rather than dealing with something (it has been known on occasion!)

macman

Bubble wrap and blankets will not protect against the extremes of heat and cold that your loft provides-but it's your choice.

googler

I'd suggest anything that needs to be kept dry in a loft should ideally be boxed up, perhaps with some silica gel sachets enclosed, and the box wrapped in clingfilm or packaging film, and rounded off with parcel tape or similar.

Seakay

my loft was damp recently because when the grant funded extra insulation was put in they blocked the under the eaves ventilation and didn't put any other ventilation in. Ventilation has to be above the insulation - if you have the current suggested amount of insulation then the chances are that the original ventilation will no longer be functioning. Basically you can pull the insulation away from the eaves in which case it won't keep your house warm, or you can have vents let into the roof. I had to have a guy in to do this the other day. I have a slate roof and the vents were put in from outside and he took about 3 hours to put 6 in. This was 4 days ago and already the dampness is lessening.

scottishminnie

googler wrote: »

I'd suggest anything that needs to be kept dry in a loft should ideally be boxed up, perhaps with some silica gel sachets enclosed, and the box wrapped in clingfilm or packaging film, and rounded off with parcel tape or similar.

Thanks, I hadn't thought of silica gel so that's a really sensible idea.

Leif

scottishminnie wrote: »

Thanks, I hadn't thought of silica gel so that's a really sensible idea.

Stationers such as Staples, as well as the usual suspects (B&Q et al) sell large plastic boxes that are ideal for storage. As said earlier get silica gel. You can buy it on ebay, don't buy the small sachets on the high street. That is how I stored camera lenses.

But would not silica gel cause the air to become too dry? Could not dry air cause shrinkage of the frame?

I don't think I would leave expensive paintings in the loft, even if boxed. Changes in temperature would surely damage the frame and/or canvas.

macman

Damp is not the main issue, temp fluctuation is. Oil paintings in particular will simply crack and craze in such conditions.

Gloomendoom

macman wrote: »

Damp is not the main issue, temp fluctuation is. Oil paintings in particular will simply crack and craze in such conditions.

True. I have a remote temperature and humidity sensor in the loft. I have noticed that the temperature fluctuates between -12°C and +36°C over the course of a year.

High levels of humidity should be expected when the weather is wet like it is at the moment, even with good ventilation. The air coming in from outside is likely to be saturated (84% here.)