If you are considering remodeling a bathroom or simply replacing a bathtub, it is important to get the correct bathtub dimensions to ensure you buy a replacement tub that is the right size and shape. The process of measuring bathtub dimensions will change slightly according to the type of tub you have and the type of tub you will be installing. If, for example, you own a stand-alone tub such as an iron claw foot tub, you will need to measure differently than if you have a one-piece tub installed into an alcove. Be sure to measure the distance at the longest point of the tub, regardless of the style of tub you own.
When measuring a stand-alone unit, you will need to measure the distance between the farthest points to get the correct bathtub dimensions. Many claw foot and stand-alone tubs are rounded or peaked in the center of the tub on each side, so be sure to stand in the tub itself and measure the distance from the peak on one end to the peak on the other. Measure to the outside lip of the tub to make sure you get the most accurate measurement. Remember that if you are replacing the claw foot tub with a different style of tub, you may need to add a few inches to the measurement to get the most accurate idea of available space in the bathroom.
The bathtub dimensions of a tub with a surround, or a lip of material that extends around the outside of the tub on either side of the tub, will be measured differently than a stand-alone unit. Measure again from the farthest point to the farthest point, and then add a few inches to account for the surround. Mark down the measurements with the surround and without it to get the best and most accurate representation of the size of the tub. When measuring height, measure from the floor outside of the tub to the top of the tub fixture. Do not stand inside the tub when making this measurement; instead, stand outside the tub and measure from the bathroom floor.
The width of the tub will complete the measurements of the bathtub dimensions. Measure from the far wall to the outside lip of the tub to get the width measurement. Once you have the length, width, and height measurements, check you measurements against the most common sizes of bathtub models to find which one will fit best in your bathroom.