Do I Need a Concrete Pad for My Hot Tub?

🧱 Do I Need a Concrete Pad for My Hot Tub? (And Other Base Options Explained)

Straight answers from the pros at Polar Springs Hot Tubs

One of the first questions we get at Polar Springs Hot Tubs — especially from first-time spa buyers — is:

“Do I have to pour a concrete pad for my hot tub?”

And the answer? It depends.

Some hot tubs absolutely require one. Others don’t. But all spas — no matter the size or model — need a solid, level, and stable foundation underneath them to support the weight of water and people combined. Let’s break down your options, and help you make the right decision based on your backyard, your tub, and your budget.

💡 First: Why the Base Matters So Much

A hot tub filled with water and people can easily weigh 3,000 to 6,000 lbs or more.

If your spa isn’t sitting on a level, stable surface, here’s what can happen:

  • It settles unevenly, causing stress cracks in the shell

  • Water doesn’t circulate properly due to tilt

  • Doors, panels, and covers won’t align right

  • Pumps and heaters may strain or fail over time

And once it’s full and wired — you don’t want to move it.

🧱 Concrete Pads: The Gold Standard

For most installations, a poured concrete pad is the best and most universal choice.

Pros:

  • Incredibly durable and level

  • Long-lasting with zero maintenance

  • Ideal for heavier tubs (especially with loungers)

  • 100% required for swim spas (more on that below)

🚫 Cons:

  • More expensive than DIY options

  • Requires time to set and cure (plan ahead)

  • You’ll need to hire a contractor if you’re not handy

Concrete dimensions tip: We recommend at least 4" thick, reinforced, and slightly larger than the spa footprint. For swim spas, we recommend 6"+ with rebar grid and edge form support.

🪨 Gravel Base: The Budget-Friendly Option

A compacted crushed gravel base is a solid option for certain plug-and-play or mid-weight tubs — as long as it’s done right.

Pros:

  • Affordable and DIY-friendly

  • Good drainage

  • Fast to install

🚫 Cons:

  • Must be tightly compacted and framed in (wood or plastic edging)

  • Can shift or settle if not prepped correctly

  • Not suitable for large or high-end hot tubs, or anything with cabinet-mounted equipment

Best for: Less expensive projects.

🪵 Deck Installations: Yes, You Can (With a Few Conditions)

Wondering if your existing deck can support a hot tub? Here’s the short version:

✅ Yes, if:
  • The deck is structurally reinforced to handle 100+ lbs per square foot

  • You’re installing a smaller-to-mid-size spa

  • You’ve consulted with a licensed contractor or engineer

🚫 No, if:
  • It’s a raised platform deck built with standard joists (too much flex)

  • You’re installing a swim spa (never goes on a deck)

  • You don’t want to reinforce or rebuild part of the structure

Pro tip: Some customers cut a “recess” into their deck and place the spa on a concrete or gravel base below — for a clean look and structural integrity.

🏊‍♂️ What About Swim Spas?

No debate here — all swim spas require a concrete pad.

Why?

  • They’re heavy — often 20,000 lbs or more when filled

  • Their long frames must be perfectly flat end-to-end

  • Uneven support leads to warping, cracks, or premature failure

👉 If you’re planning a swim spa installation, talk to the Polar Springs team about exact base requirements, pad dimensions, and reinforcement specs. We work with local contractors to make it seamless.


✅ Final Thoughts

You don’t always need a concrete pad — but you always need a properly prepared base. At Polar Springs Hot Tubs, we help you choose the right setup based on:

  • The model you're buying

  • Your backyard conditions

  • Your budget and long-term plans

Whether it’s gravel, concrete, or a custom deck plan, we’ve seen it all — and we’re here to make sure your install is safe, solid, and stress-free.

📍 Visit us at 1111 Development Drive, Brockville, Ontario
📧 Email info@polarsprings.ca or call 613-572-2777 to talk base prep and book a delivery walkthrough.