Is this damp? Or something else?

[mamapants]

Anyone know what this is, just noticed it today on an external wall.

I can't see it in your picture, but on an external wall it is most likely condensation. Open the windows.

To check, wipe it dry and tape some thin, clear plastic film tightly to the wall. If water forms on the room side of the plastic, it is condensation. If it forms on the wall side, it is coming from the wall, perhaps a leaking pipe or spilling gutter.

If you are throwing buckets of water at the wall, or draping wet washing around your home, which amounts to the same thing, it will be damp.

OK will try that, we've just run out of cling film so will have to get some. I can see it on the picture, it looks like grease splatters or something but not in the kitchen. I've never seen anything similar before.

I do dry washing in the utility room, maybe we should try and work out how to fit a tumble dryer in there. It's a struggle to keep up with the drying.

Or, if you must dry indoors, an extractor fan in the drying room, near the ceiling, will suck the water vapour outside the house. In this case get a good one with a ball-bearing motor, that will not wear out and get noisy quickly. A modern fan will typically run for about 100 hours on 10p worth of electricity, so much cheaper to run than a tumbler.

This is also why you can hang washing over the bath with the bathroom extractor running, and it prevents steam from dispersing around the house.

If you get a builder, plumber or electrician in to drill the hole, have one made close to a potential tumbler location low down, then you have the option of fitting a vented drier if you ever want to.

A high vent and a low vent will tend to ventilate a room even without a fan. Enough for a pantry, but not enough for a drying room.