The Basic Anatomy of a Hot Tub

Basic Hot Tub Anatomy - Jacuzzi
Not quite sure you know the difference between a hot tub cabinet and shell? Just what are the parts of a hot tub called? When you are spa shopping, it’s important to understand all the basic components and their function. Not to worry, basic hot tub anatomy is pretty simple, and understanding it will help you identify a high-quality hot tub. 

Cabinet and Shell

All hot tubs have a cabinet and shell. However, when you just look at a hot tub, it can be hard to know which is which by name alone. The cabinet is on the outside, while the shell is on the inside of your spa.  Specifically, the outer walls make up the cabinet. When you’re looking at high-quality hot tubs, most models will have at least a couple of options when it comes to cabinet color/style.   The shell is the sculpted interior lining. Like the cabinet, you can often choose the shell color you like. Shells are made from a variety of materials; usually vinyl, rotomolded plastic, or acrylic. The shell cannot be replaced and needs to last the life of your spa, so here is where you’ll see a big difference between entry-level and high-end models. Vinyl, found on entry-level hot tubs, is less expensive but also less durable. Acrylic, found on high-end spas meant to last for 20 years or more, is more expensive but much more durable and energy efficient.


Good hot tubs are designed to be energy-efficient, and for that, it requires high-quality insulation, just like with your home. This is another factor that affects the performance (and price tag) between high-end and entry-level spas. While premium insulation and interior components will cost you more upfront, an energy-efficient hot tub costs just $10-$20 to operate each month — saving you lots of money in the long run. 


Did you know that having a high number of jets doesn’t necessarily mean a hot tub is a high-quality one? It’s actually the position, action, and power of the jets that matters most. Read this to learn more about hot tub jets. 


Hot tubs come with a variety of seating styles. Optimally, the hot tub you choose will offer more than one type. Sometimes you may enjoy reclining in a lounge seat while other times you will want to sit and get a foot or back hydromassage. Seating is so important! That’s why we recommend you try out any hot tub you’re interested in before you buy. A test soak will allow you to try the seats and make sure they are comfortable and provide the targeted massage you need. Here are a few other things to keep in mind about hot tub seating.

Internal Components

The heater, pump, and other internal components have a huge impact on your hot tub’s performance. For instance, without a strong enough pump, your hot tub wouldn’t be able to pump enough water through the jets to give you an effective hydromassage.  Now that you understand the basic anatomy of a hot tub, and why it matters, we invite you to visit us at Fronheiser and check out our selection of awesome hot tubs in person! We’ll answer all your questions and help you find the ideal spa for your needs and budget. With models from Caldera® and Freeflow®, you’ll find the perfect hot tub for all of your needs — only at Fronheiser.  
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Fronheiser Pools

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