Preparing a tiled bathroom wall for painting- tips please?

Can you advise best ways of cleaning the grout- very discoloured in places and must I regrout before painting over?Preparing a tiled bathroom wall for painting- tips please?
What you need to do first is sand it. So you need a electric sander. The grout does not need to be replaced but just cleaned. When you sand this will help clean also. Next you need to use a product like Killz. Its a base primer that prevents mold growth. Grout is famous for mold. Then you paint. But you need to use a sprayer to get a realy good effect. I'm including a link for you.Preparing a tiled bathroom wall for painting- tips please?
Depends on how 'professional' and 'perfect' you want to be...and how much work you want to put in. I did my bathroom and got all kinds of advice...but the recommendations were long and involved. I ended up cleaning the tiles well with TSP and then priming and painting. I regrouted lightly, after the paint had dried, because I wanted a clean and finished look. At the end, I sealed it with a high gloss sealer. It was all very quick and easy...and very little mess.
The grout can get bleached tokill any mildew or you can get a grout cutter and cut out the old anr put in new this would be the best especially if the old grout is showing signs of wear such as cracks. to prepare the tile itself you can either sand the finish with sandpaper to remove the gloss or you can use an acid etching. Not taking the shine off will make it difficult for the paint to stick meaning every time you brushed up against it it would scratch the paint right off. As for a kind of paint an epoxy or arcrylic enamel thats designed for painting on tile will work best and be sure to check the prep. recomendations on the can for best results. Good Luck!
if painting over all the tiles, why bother re-grouting.
if you must paint the tile, you need to make sure the tiles and grout are clean and mildew/mold free. I would clean with a bleach/tsp mix, then use a latex primer on the whole area. I don't know why you would want to regrout, that wouldn't make any difference, and you would have to wait for the grout to fully cure before painting. I would suggest Benjamin Moore's Fresh Start All purpose primer





Just wanted to comment on the previous answer--Kilz is an oil base primer, and I would not recommend that for this application. Also, It DOES NOT kill mildew, in fact, oil based products are MORE prone to mildew than latex. the name kilz doesn't mean it kills mildew, it is a stain KILLING primer. I sell kilz, but would not suggest using for this application.
use cillit bang or something similar.then use grout to repair damaged areas