Perhaps you have discovered a crack in your hot tub shell; it might be a small one and very shallow, or it may be only a blister in the acrylic surface. All these are likely to occur in hot tubs, especially older ones or those exposed to harsh conditions — sometimes leading to issues like a hot tub pump leaking. However, there is no need to panic, as most of the cracks on the hot tub can be repaired at home using proprietary products.
This guide also relates to other spa issues, such as hot tub pump problems, diagnostics, homemade repairs, and when to call a professional. It is the place to be when it comes to acrylic spa shell damage, leaking hot tubs, or cosmetic surface cracks.
Hot Tub Crack Types and Damage
Cosmetic Damage to Surface: Cracks
Surface cracks appear in most bathtubs in the form of light marks, spider lines, or simple discoloration of the acrylic coating. In the vast majority of cases, it is not severe; it does not reach to the shell below. It is not pressing but can be spread as time goes by without correction.
Shell Cracks (Fair Structural Problem)
Fractures in the spa shell are not good. They will release the water so get them repaired as soon as possible. These are normally the result of impact damage or long-term wear. You can observe that it bubbles, peels off, or has little holes.
Structural Cracks (Severe Damage)
When the crack extends far or to the fiberglass layer beneath the acrylic, it has resulted in structural damage. Such cracks can weaken the entire tub, most commonly in the form of leaking water or even collapse of the shell.
What Leads to the Hot Tub Cracks?
Knowing the causes of cracks, you will be able to avoid those in the future. The most common ones are the following:
- Imbalanced water chemistry (low pH, high levels of sanitizer)
- Cold weather and poor hot tub winterization often lead to cracks caused by freezing water.
- Severe use or impact damage
- Ineffective manufacturing of slim acrylic shells
- Age-related stress fracture and wear
How to Crack Check and a Spa Shell and Check and Identify Cracks
Before you fix anything, diagnose the sort of damage and the extent:
- Visual Examination: Look at the small cracks, bubbles, or even the color change.
- Surface Cracks May Feel Slightly Raised or Even Sharp: Sometimes rough patches on the surface of the skin may feel a bit raised or even sharp.
- Check and See if it has Water Leaks: The water leak can occur through the spa shell.
- Dye or Pressure Tests: Use some food coloring or a pressure gauge to identify leaks — similar to the process explained in our hot tub pump leaking guide.
DIY Hot Tub Crack Repair: How it is Done
If you are handy with tools and the damage is not too extensive, then here is how you can repair it yourself.
a. Assemble The Tools and Materials
You’ll need:
- Hot tub fix kit
- Fiberglass or acrylic filler
- Sandpaper (different grits)
- Scraper knife or scraper
- Protective goggles and gloves
- Gel coat or acrylic topcoat (optional)
b. Drain the Hot Tub and Dry it Up
Cut the power and empty the spa. permit a dry surface; no bonding should occur in the presence of moisture
C. Sand Damaged Area
Clean the area around the crack and smooth the surface with fine-grit sandpaper to provide a superior surface to which the filler can bond. You then should wipe off any dust or dirt that has settled on it.
d. Use the Filler
Make use of an epoxy filler or acrylic to fill the crack using a putty knife or applicator. In deep cracks, repeat the coating a number of times, allowing each coating to dry before the next is applied.
- To make epoxy waterproof better, marine-grade epoxy should be used.
- Smooth the surface as well as you can
- Follow the drying time as recommended by the manufacturer.
e. Let it Heal and Sand Smooth
Once cured (this typically takes 12-24 hours), sand the repaired surface once more to obtain a smooth finish. Clean using a damp cloth.
f. Apply Top Coat or Gel Coat (Optional)
To make it look complete, once the repair is done, paint the spa in an acrylic gel topcoat to match the original color.
g. Top up the Spa and Test
Reconnect power carefully and make sure there’s no leakage or electrical issue — if your breaker trips, check our guide on hot tub GFCI keeps tripping.
When to Have a Professional Crack Repair Hot Tub
It is cheaper to do the repairs by yourself but not always the most suitable way. Consider hiring a pro:
- A crack that is more than 6 inches or one that penetrates through the shell
- That tub is leaking again despite the fact that it was fixed
- You are not really certain about these electrical parts near the crack.
- Damage to plumbing or jet systems is affected
The Following are the Hot Tub Maintenance Tips to Avoid Future Cracks
Prevention is better than cure of cracks before they open. These are some tips:
Stabilize Water Chemistry
- pH: 7.2-7.8
- Alkalinity total: 80-120 ppm
- Calcium hardness: 150250 ppm
- Chlorine or bromine Sanitizer: acceptable concentrations
Guard Against Freezing
- Before the cold weather, be sure to drain your spa and have it winterized.
- A proper spa cover should be used
- Keep the winter heat low.
Check the Shell Monthly
- Check to see whether there are blisters, cracks, peeling, and bubbles.
- Monitor the water level carefully and watch out for any concealed leak.
- spa shell inspection, hot tub maintenance routine
Suggested Crack Repair Tools & Products
Some of the essentials of a hot tub owner are:
- Leak Seal Acrylic Spa Repair Kit
- Marine Grade Epoxy/Waterproof
- Sandpaper Set (Fine and Medium Grit)
- Touch-Up Kit Color-Matching Gel Coat
FAQs
Is It Possible to Fix a Cracked Hot Tub Shell?
Yes! The cracks in acrylic and fiberglass can usually be repaired using epoxy or acrylic filler.
What Cracks the Shell of a Hot Tub?
Some of the general causes could be things such as imbalance of water or freezing of the water. Or there may be impacts or just normal wear with age.
What do I do to Repair a Leaking Hot Tub?
Where it is leaking, empty the tub, then use a repair kit on the hot tub to seal the crack.
Which is Better in Spa Shell Repair acrylic or Epoxy?
Epoxy is good at waterproofing, but acrylic blends in better.
How Much to Repair a Cracked Hot Tub Shell?
Repairing on your own could cost you anything between 30 and 100 dollars. On the one hand, a professional may not be cheap.
Conclusion
Cracks in hot tubs are enough to make you panic, but they do not always mean a full-blown disaster for your hot tub. With the proper diagnosis, repair procedure, and tools, the hot tub can be repaired and the additional damages prevented.
Provided you are feeling bold enough, then you can go ahead and attempt the DIY hot tub crack repair using the guide above. However, in case you feel apprehensive or the damage is too serious, then by all means, call in a professional spa technician. A hot tub is a significant purchase—safeguard it the intelligent way.
