Tri Ply is a term you will come across often when searching for stainless steel cooking ware. The term is used interchangeably with clad and 3 ply. In simpler times, cooking utensils were made of just one metal–stainless steel, aluminum, cast iron, etc.
For whatever reason, manufacturers decided to bond more than one metal together when producing cooking utensils resulting in a three layers. In the case of stainless steel, this was not a bad idea. Tri Ply is important to this metal because stainless cookware alone does not do a good job of cooking food without this layering.
Tri Ply or clad, is essentially the sandwiching of aluminum or copper between an outer and inner layer of stainless steel because it isn’t a metal that distributes heat well.
Aluminum and copper are metals that do. So by layering one of these metals between stainless steel, you can now have pots and pans that heat evenly and thus, cooks food evenly, avoiding problems of hot spots in your food.
It isn’t the only form of layering. There are a few brands that feature 5 ply as well as 7 ply cladding. The more layering a pot has, the more expensive it is.
Tri ply construction or cladding is found mostly on the bottoms of the pots and pans and often looks like a disk. Some brands extend the cladding up along the sides of the pots and pans as well.
All Clad is the most popular brand for using this extended construction of fully clad cooking ware. It comes with a hefty price, too. But there is a highly regarded alternative as well. So the question becomes, does cookware that extends the tri ply construction to the sides cook better than cladding only on the bottom?
Fully clad pots and pans do not have the benefit of being certain that even heat continues beyond the bottom. However, thickness of the material used in the cladding (aluminum or copper) plays an important role, too.
A set of pots and pans with good quality construction is perfectly capable of heating food evenly along both the bottoms and sides especially for smaller pots like saucepans and fry pans even if it is only limited to the bottom.
My recommendation would be to first look for quality cookware from reputable brands. Then choose the type of layering that best suits your cooking habits, family size and budget.
If you are a serious cook, you may want to invest a reasonable amount of money in fully clad cooking ware. But if your cooking habits don’t warrant spending a lot of money on any pots and pans, then by all means go with tri ply cookware that has this layering only on the bottoms of the cookware.