What's The Difference In Mil & Gauge?
Both terms describe a liner's thickness. A mil is one thousandth of an inch and is regulated, while gauge is an unregulated estimate.
Mil and gauge are both used to describe how thick a vinyl liner is, but they are not the same kind of measurement.
Mil is a true, regulated form of measuring the thickness of a liner. One mil is one thousandth of an inch.
Gauge, in vinyl liners, is not regulated. It is more of an estimated thickness based on findings rather than a fixed unit.
That is why you will see liners sold in mils more often than in gauge, and why comparing a mil figure against a gauge figure is not a like for like comparison.
Does a thicker liner last longer?
Usually not, and this is the question behind the question. We have sought answers from liner manufacturers, pool builders and retailers, and most do not believe thickness is a deciding factor in most cases.
Many professional builders actually prefer 20 mil liners, because the extra elasticity helps them fit better. Thicker liners are less pliable and much heavier, which can make installation more difficult.
A properly fitting 20 mil liner will outlast an improperly fitting thicker one.
There are cases where thickness helps. Liners of 27 mil and above give more protection against abrasive pool surfaces and punctures. Liners do not normally fail from either, but the extra protection can be a benefit.
What about fading?
Thicker liners do not fade less. A 20 mil and a 30 mil liner use the same clear coat protection layer.
Liners fade for four reasons: chemical erosion, sun fading, overstretching during installation, and age.
Over-chlorinating is the number one cause. Any chlorine level above 3 PPM will accelerate fading, in much the same way excessive bleach fades clothing.
So what should you choose?
Our recommendation is to choose your liner based on the pattern you like best, rather than passing up the pattern you want because of a thickness figure.
Read more
- Our blog post comparing 20 mil and thicker liners covers this in full.
- For help choosing color, texture and pattern, see our guide to choosing a pool liner.
- Browse our inground pool liners or above ground pool liners.
Still need help?
Didn't find the answer you were looking for? You can always contact us at support@royalswimmingpools.com or choose the category below to see our most frequently asked questions for that topic: