For our current bathroom we picked up this bath from eBay, it's from the Heritage range of and is plastic rather than cast iron. It was white to start with but we knew we wanted to paint it a dark grey.
to paint a bath tub you'll need to use a primer first. We use this one to coat everywhere that you want to paint. Once it's dry you can paint on your colour. Use eggshell paint. We needed two coats and used Farrow & Ball Eggshell paint in Plummett. You'll only need a small tin.
To paint a cast iron bath: You shouldn't need to prime it, most baths come pre-primed so you should be able to use eggshell paint straight onto it.
Don't layer it on too thickly and use a brush for best results.
You can decide if you want to paint the feet the same colour, a contrasting colour or leave them as they come. In our last bathroom we painted the bath and feet the same colour, in this one we've left them black for now as they came but I'm planning on painting them either white or the same grey as the bath. I don't think the black is quite right.
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