Standard Bar Stool Heights
The standard bar is 42 inches high, which is 3 inches lower than your 45-inch bar. Most standard bar stools are therefore built for the 42-inch-high bar, and have a seat height of between 26 and 28 inches from the floor. Therefore, raising this height by 3 inches to at least 29 inches and no more than 31 inches will properly seat your guests at the bar, with plenty of legroom and easy access to their drinks or food.
Raise or Lower the Bar Stools
Raising or lowering the bar stool heights for your 45-inch-high bar is another way to customize your bar. You can adjust the height to account for the different leg and torso sizes of guests, making each stool individually tailored to everyone in your family. Or, make the stools all the same size, if you own a public bar. Using the average stool height as a guide will ensure most people are comfortable, because these averages are based on the average adult height today. You might also consider adding a few lower and higher stools to suit different customers that come into the bar.
Legroom and Bar Access
Another factor you need to consider is legroom under the bar and the customer's access to the bar top. The customer must be able to sit comfortably on the stool with his feet propped on one of the stool rungs. The legs should not touch the underside of the bar top, and for the most comfort, the upper legs should extend out at a 90-degree angle. If the bar top overhangs the stools and is more than 3 to 4 inches thick, some people may find this hard to do. In this case, consider stools that are on the low end of the recommended height.
Custom Bar Stools
In order to add stools to a 45-inch-high bar, you might have to buy custom-made stools. This incurs more expense in most cases, but you will end up with stools that seat guests very comfortably at your bar. Another option is to buy high bar stools built with seat heights of 31 inches or higher as a stock item. Many bar stool retailers and even some large retailers carry and stock these items regularly. Adjustable-height bar stools will add even more convenience and usability to your bar.