You should not re-grout over existing tiles.There are many ways to brighten up the grout. Rejouvinate is one product available. You also can try toothpaste and a small brush.
@Janet Pizaro Thanks Janet. I think Rejouvinate is available here in Melbourne. Good to know that it's effective. Cheers.
I have also used grout colorant to change the color of grout. http://www.homedepot.com/p/Custom-Building-Products-Polyblend-10-Antique-White-8-oz-Grout-Renew-Colorant-GCL10HPT/100096585
It's rather tedious but it does work.
@Paper Daisy Design Thanks so much for your suggestion. I will see if that product is available in Australia. Cheers.
i use a thick paste of Comet and water. leave it set 10-15 minutes. use the very stiffest nylon brush you can find (i use a Dep grout brush from Home Depot). )very, very labor intensive but nothing i have ever tried works as well. . not baking soda/vinegar, peroxide, nothing. i would love to find something better but even Rejuvenate has not held a candle to this mixture. i have alabaster color grout and unglazed porcelain tile..
@Grant HI Grant, Thanks so much for your suggestion. I've never heard of Comet before, but I will investigate. I guess the trick is to keep the grout white. I appreciate your help.
A product called THE WORKS(used to clean toilets) will clean dull tile. If you are sensitive to hard chemicals wear gloves and open a window(pretty strong). Squirt on, let set then scrub and finish with a final rinse!! Or take a screw driver and scrape the grout(top surface) and re-grout with a similar color and seal!
@Thank You Isabel Pennington I think I may give the scraping and regrouting a try to get a consistent look. Much appreciated.
Hi, where did you get your door? And the hardware for it?