How prepare sweaty/oily bedroom wall for painting?

[John]

I'm going to paint the walls in a bedroom.

One wall has got a large discoloured patch above the bed which looks as if it's made up of something like sweat, hair oil, etc.

I would have used Sugar Soap to clean this wall but I heard that Sugar Soap would probably cause lifting of the wallpaper which is under the existing emulsion paint. Is this true?

Is there an alternative cleaner to Sugar Soap which I can use to degrease this wall?

Or would I get away with a VERY light Sugar Soaping of the wall using little water and little rinsing.

Thanks! John

[Cicero]

================================== Try a dry solution; a warm domestic iron over a piece of thin paper. This works for removing oily / greasy stains from clothing so it will probably remove most if not all of the offending stain.

Cic.

[Autolycus]

It might do - after all, it's not that different a process to the way you'd start to strip it... so why not just strip it anyway?

That way, you'd be sure the marks weren't going to grin through the paint, and you'd have the chance to use a wallpaper (painted or otherwise) or lining paper of your choice. There's always a chance that painting a wall will loosen old wallpaper, leaving you with a horrible, bubbled appearance, so go on, make a job of it, and re-paper the whole room - or at least the wall concerned.

[George (dicegeorge)]

either the patch is through people sitting on the bed and rubbing sweaty hair etc against it, or its like my walls where the patches are from damp coming down from the roof...

in which case stop the damp first..

[The Natural Philosopher]

Swaety, oily, paint?