For many spa owners this is not a
problem... that is, if the spa shell is made with an acrylic surface and a
reinforced fiberglass base. On these types of spa shells, the acrylic surface
will sometime crack in many places, but the fiberglass that it is attached to
ensures the watertight integrity of the shell. The biggest advantage of this
type of shell is that it is probably the strongest type of material available.
You can move it, drop it, rough handle it, abuse it, and it usually won't ever
crack all the way through.
When you actually have a REAL problem, you'll know it, because water
will start leaking out of the shell. At that point, it's time to drain the spa,
let it dry, and patch the crack with a fiberglass repair kit.... the same type
used to repair boats and cars, available under the "Bondo" trade
How do you know if you've got a
reinforced fiberglass shell? If you can see the shell underneath the skirt, and
the shell doesn't flex with pressure applied by hand, then it's probably
fiberglass reinforced. You can also tell by looking at the lip edge of the
shell. Usually on this type of shell, the edge of the shell material will be at
least 1/4 to 1/2" thick. Upon close examination, you will be able to see a
thin layer (the surface acrylic) and a thick greyish looking layer which is the
Other types of spa shells may not fair
so well. Some of them are made with only a thin acrylic layer form, and
supported by "full foam insulation". In other words, the foam
completely fills the spa cabinet. These shells are pretty fragile and do not
have the durability that a fiberglass reinforced shell does.
In this case, getting the cracks to
stop cracking any further is extremely important, because once a crack in a
shell like this gets more than say 3-4" long, it really loses a lot of its
ability to keep from contining to separate, even if patched and
The best solution with a shell like
this is to "hole stop" the crack. Drill a small hole, (approximately
1/16" diameter) at the very tip of the crack.
For short cracks of less than 3",
a 1/16" bit should do fine. If more than 3" use a larger bit,
preferably a 1/8" diameter. The larger hole allows for more expansion and
contraction that a longer crack is likely to endure, without fracturing
The round hole will create an area of
structural integrity by virtue of its round shape, and it shouldn't crack any
further, unless of course, stress is continually induced here, or if the
plastic material has aged such that it just won't hold
Once the hole is drilled, it's time to
fill the crack and hole with any type of a good plastic sealant material, such
as "plumbers GOOP", plastic cements that are thick bodied that have
"filling" characteristics, and in some instances, even 100% silicone
caulk will work.
Prepare the area for the sealant by
cleaning it with denatured alcohol. Only apply the alcohol in the
immediate area of the crack, about 1/2" on either side. Let it dry for
about 4 minutes and then apply the sealant over the cleaned area, with an
overlap of about 1/8-1/4" on either side of the crack.
To repair a shell in this manner may
take a couple of attempts, including draining, drying, and refilling the spa to
test for watertight integrity. But in the end, it's still a lot cheaper than
replacing the entire spa, which is usually the only other solution to the
If you have ever repaired a spa shell
crack and have discovered other ways of fixing them, please
email us here and let us know!
We'll try it out and if it works, we'll get your submission included here with
this page.... Thanks