Amount of Fabric Needed for Suit and Pants

Four is way more than enough. A typical formula for an average sized man is 1.5 for pants, 2.5 for a jacket, 3.5 for a suit. Get four anyway just to be safe.

I thought it was 4 yards?

Talk with your suit maker to be sure.

In yards you want 3 3/4 for a suit, 2 1/4 for jacket 1 3/4 to 2 yards for a trouser. In meters a bit less.

Better to have a bit more than too little cloth. Especially if you must cut the suit one way.

A tailor will use less cloth, a CTM house will require more cloth to be safe.

I will said HK tailors use much less cloth than their western brothers.
For 6 feet, 3.25m is enough for suit, if it doesn't have large pattern.

I have suits made in solid fabrics with 3 meters and I am 6'1. I have had suits made with an extra pair of trousers using 3.8 meters.

for conversion between imperial and metric, 1 metre equals 1.08 yards

Isn't that where the saying, "The Whole Nine Yards" came from?

How many yards or meters of fabric does a vest require, Chris?

The saying came from wwII fighter pilots that had 9 yards of 50 cal ammuntion on a belt. When they unloaded on enemys they gave them "the whole nine yards"

+1. And how many yards/meters does a DB jacket require too, if you don't mind?

What is a safe amount for a 3 piece suit, if the vest is to have enormous lapels as seen in pictures from Sator and, on occasion, Manton?

Unless you are just really huge, or your tailor really has a problem cutting, five yards can make a three piece suit for anyone.

No, that came from the ammo strips in Vietnam era helicopter-mounted automatic rifles. One box contained a strip nine yards long.

At least, that is what a military guy told me once.