Step-by-Step DIY Bathtub Installation

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This is an article on Do-It-Yourself Bathtub Installation. Are you renovating a bathroom to increase the value of your home, as a selling feature to attract buyers, or for your own personal pleasure? Maybe you’re constructing a new home? In any cas

There are some DIY projects that you shouldn’t attempt on your own without proper knowledge and training, such as electrical work. However, there are plenty of areas that DIY can help you keep your budget in check and save yourself the inconvenience of scheduling around a contractor. Bathtub installation is one of those areas. 


A bathtub can be placed once the rough plumbing has been installed or, in the case of a renovation, the old tub has been removed. Let’s look at your options: 

• Alcove tub – this apron front tub is installed between two walls. It’s generally considered the easiest, fastest, and most commonly installed tub. 

• Drop-in tub – a tub deck will need to be installed first. The tile and finishing will also need to be in place. Then, the drop-in-tub is placed within the deck. 

• Undermount tub – it too will require a tub deck, but is placed into an unfinished box. Once in place, the slab deck is then placed over the tub. 

Installation Tips

• Always follow manufacturer instructions so that your warranty won’t be voided. 

• Always check your local building code ordinances and follow them exactly. Aside from safety reasons for your own family, should you ever want to sell your home, a buyer’s inspection that finds an out of code bathroom could be a costly deal breaker. 

• Don’t attempt to install a tub solo; a minimum of two people will be needed to prevent injuring yourself and/or your tub. 

• Measure twice and cut once. 

Installing An Alcove Tub 

The easy installation makes alcove tubs a fan favorite. Again, it’s absolutely necessary that the rough plumbing is completed beforehand. Since tub surround or tile will take about an inch of space, the unfinished walls surrounding the tub should be about an inch larger than the tub’s measurements. Install your tub as follows: 

1. If the water is turned on to the tub’s plumbing, it’s prudent to turn off the water supply at the butterfly valve or ball valve to prevent accidents as you're maneuvering the tub into place. 

2. Use a measuring tape to get the tub's height. Measure and mark this height out onto the back wall of where the tub will be placed. Locate the studs at the corresponding height and screw a row of 2x4s. 

3. The tub’s apron should be facing you, the back of the tub should be toward the stud wall, and the drain and overflow side of the tub should be toward the wall with the plumbing. Now, carefully begin to maneuver the tub until it’s resting on the support ledge and is flush with the stud wall. 

4. Locate the flange and screw it into the studs. 

5. Connect the back piece of the overflow and drain to the plumbing, screw the overflow face plate on, and connect the drain piece. 

6. You’re ready to do your tiling or surround and install your faucet. 

Installing An Undermount Tub 

A paper template that provides the precise dimensions of the surround box will accompany your tub. The template will also be used by the slab deck manufacturer. The deck should be constructed per the manufacturer’s requirements. Remember that your tile shouldn’t be installed at this point! Here are the steps of installation: 

1. Fill the base of the surround box with about 2 inches of dried, crushed mortar. 

2. The tub will now be lifted and placed in the unfinished surround box. 

3. You’ll need to weight the tub with water so that it can settle into the mortar. Rags can be used to clog the overflow and drain holes. 

4. After letting the water out,connect the overflow, drain, and plumbing on the tub deck. 

5. A professional can now install the slab deck. 

Installing a Drop-In Tub

You’ll also have a template with a drop-in tub. This pattern will be used to cut the plywood for the top deck, which will create a hole for the tub to drop in. The steps will be the same as with an undermount aside from having a finished, tiled surround and placing kitchen or bathroom silicone around the surround of the tub while it’s weighted with water. 

1 comment

Guimo Pantuhan
Posted on May 17, 2012