Installation/Technical information

How do I install my tub?

All of our whirlpool tubs can be installed in at least one of three possible ways:
Below, we will explain how each of these three methods work, which tubs are applicable, and we will list tips and tricks for installing your tub for each one. This guide works for both Whirlpool Bath Tubs, and Air Bath Tubs.

Need help choosing between a whirlpool and air tubs? See our guide!

The Drop-In Method

The drop in installation method is the most common installation method for really nice whirlpool baths. You build a raised deck that comes up to the lip of the tub enclosing everything below. You can use tile or marble for the deck top that can be just a few inches larger than the tub or you could have several feet of extra tile top. It’s a nice place for plants or flowers or candles.

Start by determining the depth of the tub so you know how tall your deck needs to be. You want to find the measurement from the underside of the lip of the tub to the bottom of the tub, where the feet or bottom support of the tub is. Basically with the tub sitting on the floor you would measure from the floor to the underside of the lip. Keep in mind that tubs that do not have support feet will sit crooked on the floor because the bottom of the tub is pitched so water runs toward the drain. When the tub is set in place with the top lip level you will have the correct pitch at the bottom of the tub for full draining.

Once you have established that dimension you should add an inch or two to that measurement. If you build your deck a little too tall it’s simple to shim up underneath the tub to close that gap but if you build your deck a little too short the tub will stick up too high when you set it in place and there isn’t anything you can do about that. So build the deck slightly higher than what you think you need.

The idea is to build the structural part, the base of the deck using 2x4 or 2x6 lumber and plywood. You want to get the framework done but leave the front open. If you plan to use tile or marble for the top you will probably want to use 2 layers of 3⁄4” plywood so there is no movement and your tile or grout won’t ever crack. Personally I would also use construction adhesive or wood glue between the layers so it is super strong and with no movement. Make sure you factor in the thickness of your framing materials and your tile thickness with mortar so you end up with a finished height, from the top of the tile to the bottom of your enclosure that is slightly more than the height of your tub from the underside of the lip to the bottom of the outside of the tub. Feel free to call us at 1-800-809-9111 if you would like to speak to an installation expert.

The opening in the top of the deck should be approximately 2” smaller in diameter than the overall diameter of the top lip of the tub you are installing. 2” overall would mean that when you set the tub into this opening the tile will extend 1” under the lip of the tub all the way around. Check the tub to make sure nothing below the lip extends out farther than the lip. Remember the lower part of the tub has to fit through this opening so check that out. Some whirlpools have pumps or fittings that may stick out beyond the footprint of the top. Normally that isn’t a problem because you can set that end in the opening first, slide the tub centered over the opening and it fits. If a tub has a pump on each side that both stick out slightly beyond the top lip you will need to factor that into your installation plan.

Make sure you have proper clearance for your waste and overflow kit too. Hopefully you have reasonable access from the front of the deck and your access panel. Once the tub is set in place you can reach in there and get the drain pipes glued together. If you have the clearance you could install the waste and overflow kit into the tub before you set it into the opening for the final time. Once you put that drain fitting on you need to be very careful with it because the drain hangs off the bottom and could easily crack or break if set down with the weight of the tub on it. If the clearance allows you could set the tub in place first then install and connect the drain kit. This will vary based on your specific installation.

At this point you can install the tile or marble top and tile right up to the edge of your opening. Once your tile is finished, grouted and set you can test fit the tub. Set some 1/8” wood shims around the edge of the opening on the tile top. Carefully set the tub into the opening and gently lower it down onto the shims. The bottom lip of the tub should not set directly on the tile or marble, it should rest only on the shims. Do not step into the tub while it’s hanging from the tub lip. Once the tub is in place look into the open front of your deck at the gap between the bottom of the tub and your floor below the tub. You want somewhere around a 1” gap. If the gap is a few inches, use scrap plywood, 2 x 4, 2 x 6, whatever is needed to build up the floor to reduce the gap to about that 1”. Screw those shim pieces together so they don’t shift of move. If you have about a 1” gap you will only need 1 bag of Portland cement to set most tubs into. If your gap is too big you will need a bunch of heavy Portland cement to fill that gap and that isn’t good or necessary.

Remove the tub from the deck and for simplicity you can have a couple of 2 x 4’s nearby that you can set across the opening in your tile deck top to set the tub on temporarily. Mix some Portland cement powder, not concrete mix. You want a smooth cement mixture without aggregate. Normally a single bag, 40 lb, 50 lb should be enough. You want to mix it to a consistency of approximately peanut butter. The idea is to pile the mortar up several inches tall in a few uniformly placed piles directly under the bathing well of the tub. (Baths that have support feet built into the bottom from the factory don’t require the piles of mortar but it’s still a good idea to mortar or glue the feet down so there is no movement.) Once you have the mortar in place you carefully lower the tub down into the opening and into the mortar. Gently press the tub into your bed of mortar until the bottom lip of the tub just touches the shims. You do not want to force it into the shims. It must only lightly touch the shims. Assuming your tile deck it completely level make sure the lip of the tub is also completely level and just touching the shims all the way around. Do not disturb the tub and let the mortar harden overnight.

Once the mortar is hardened gently remove the wood shims. Wiggle them back and forth and gently ease them out. If you just pull them straight out you might chip the acrylic at the edge. After you have all the shims removed the tub should be completely supported from below and not hanging from the lip. You should have approximately a 1/8” gap between the top of your tile and the underside of the tub lip.

These tubs are all water tested before they leave the factory but a lot can happen between then and the time of final installation. For that reason, before you enclose the front of the deck you need to test the tub. If something got bumped, cracked, etc, now is the time to find it.

Make all your final drain connections and plug the pump or control box into your GFCI 120 volt receptacle. Fill the tub to check for leaks. If you don’t have the faucets completed at this time use a garden hose from another area where there is water available. Fill the tub to a level just over the highest jets. Turn on the pump and check everything over. Make sure it functions properly and check the lower areas for leaks or any sign of water.

drop in bathtub install guide

Once you’re satisfied all is good with the tub, no leaks, no problems, you can enclose the front. Keep in mind that you need to provide an access panel that will allow you reasonable access to the side of the tub with the pump and controls. A reasonable sized access panel must be part of the plan during the initial construction. If you or someone working for you choose not to build an access panel in right away, and you have some minor issue down the road that needs to be dealt with, you are going to be the one that gets to figure out where to cut through walls to gain access. It’s much better to install one right away so it’s in the right place and hopefully you will never need it.

Finally run a small bead of clear or colored 100% silicone rubber into the 1/8” gap between the tile and the tub lip. Make sure you force the silicone into the gap so it goes under the lip of the tub. The silicone will effectively form a rubber gasket between the tub and the tile acting as a cushion and at the same time seal that gap so water will not leak into the underside of the tub.

You can speak to a whirlpool bath expert free weekdays 10-6 and weekends 10-3 central time. Call us at 1-800-809-9111

The Alcove Method

      Most rectangular models can be alcove mounted. This means that you have walls on up to 3 sides of the tub, then you tile right down onto the tub. To achieve this, you can either purchase a tile flange kit from us that will come pre-installed, or you can use one of the other below methods. Looking to make a tub/shower combination? An Alcove installation is probably the way to go. Alcove installations allow for splashed water to fall back into the tub, and not sit on your decking around the tub.

      An alcove installation has walls on 3 sides of the tub. Most rectangular models can be installed in this fashion. Alcove bathtub installations are beneficial when you are tight on space and want to fit a nice whirlpool bathtub into a small area, or when you are replacing a previously existing bathtub/shower unit. Alcove installations are perfect for bath/shower combo setups. For recommendations or help choosing a bathtub to fit your own personal alcove installation, please call us at 1-800-809-9111.

      We offer a tile flange kit to make these types of installations easy. The ABS tile flange kit consists of a thick sheet of ABS plastic that is rivited to the vertical lip of the bathtub. This ABS sheet sticks up above the top edge of the tub and provides you a flat surface to lay tile over. Simply tack the ABS tile flange to your studs as shown in the diagram to the right, then run a thin bead of 100% silicone along the seam between the ABS tile flange and the edge of the tub. This will create a waterproof seal. We can install an ABS tile flange on any rectangular whirlpool models, and we can install it on any or all 3 sides of your tub, so you can do a full alcove install, or a 2 sided wall, or a single wall.

      Once you have the tile flange fastened to the studs, and the gap between the flange and the tub sealed, its time to install your cement board. The tile flange allows you to put your cement board right over the flange so its meets up with the edge of the top. Place a bead of a waterproof silicone sealant between the tub edge and the bottom of your cement board, and you're ready to tile! Tile right down to the tub, and you've just successfully completed an alcove install! Don't forget to use waterproof 100% silicone, not latex silicone, and use a waterproof grout on your tile.

      With any rectangular tubs or corner tubs, we offer a front skirt. We have a 1 piece skirt that can be mounted to be removable. Or we have skirts with an access panel that comes out so you can service your motor if ever necessary. The skirts are a piece of matching acrylic that fit to the front of the tub. You can mount them any way you'd like, or you can have them factory installed for a small fee. Please contact us at 1-800-809-9111 for additional details and pricing on our skirt options.

alcove bathtub installation guide

alcove bathtub installation guide

The Undermount Method

      It is possible to undermount many of our models. To undermount a tub means to have the tub opening placed below a covering, usually made of marble or stone. This requires a tub with a completely flat edge. There are many models that we sell that can be undermounted, but it requires special planning before the purchase, as we need to relocate many of the tub's controls. If you are interested in undermounting a whirlpool from Leisure Concepts, or you would like to know which models can be undermounted, please contact our sales specialists at 1-800-809-9111, or email us at

Read more about bathtub installation: LC Pro Install Guide