Yes, that is completely normal - my ex bosses son was close to 2 and half before he walked and so was a colleagues neice - my neighbours wee boy was about 17 months and one of my son's friend's little sister just started walking at 19 months. Within a couple of months, you can't tell whether they have been walking for year or just started. Don't worry, in fact, my neighbours son has just turned 3 and can ride a bike without stabilisers, so being a late walker doesn't seem to have affected him too much!
If he will walk round furniture, try moving it so that he has to reach across between two pieces on the route and see if he will get fed up of going down to crawl and back up and tries to just take the step between.