Sugar soap before painting walls??

[pineapple]

I'm painting a spare bedroom that hasn't been done since before I moved in years ago. The walls are really filthy - not helped by the dust and dirt from recent repair work. Usually I just vac and wipe with a cloth but I think this calls for a bit more prep.
Would a wipe down with a damp sponge be OK? (I know to work up from the bottom).
Or should I use something like sugar soap or even just a weak solution with dish washing liquid?

 

[kbdiy]

I guess a lot would depend on what has been on the walls before as to how much prep is needed. If there has been wallpaper before then to make sure all traces of adhesive have been removed, sugar soap might be a good idea, otherwise just plain water if it is only dirt and dust.

Curious though as to why you would work from the bottom up? When washing down the dirty water will always run down the wall so will cover the area you just cleaned. Always work top down when cleaning.

 

[pineapple]

Well all the advice I have seen on the net says to dust from the top downwards but with damp cleaning to work upwards - otherwise any cleaning solution running down a dirty wall could cause a build up of streaks that are difficult to remove.

 

[deandiy61]

evening pineapple. Agree with cleaning from bottom up. I did the same when cleaning cars, otherwise some cleaning products left a drip streak that needed T-cut to remove.