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itredler
Bath drain size

I need to replace my corroded bath drain so bought a new one but it does not fit. The new one measures 1.75" in diameter where it threads to the bath drain but the old one measured 1.5". I thought these fitting had a standard size so can someone explain this? The specs on the new one say 1.5" but it definitely measures more.

dj1
Re: Bath drain size

We can't guess what you have. You need to disassemble it, then take it to a plumbing supply store. They should be able to match it exactly.

Mastercarpentry
Re: Bath drain size

Most newer drains are 1 1/2", but some are 1 1/4". Many of the old "claw foot" tubs used an 1 3/8" drain which has become something of a specialty item that many plumbing suppliers don't stock but can order for you.

About half of what I know about plumbing was from advice given at plumbing supply store counters. You'll never get that from a clerk at a 'big box' store so if you're going to become a DIY'er, make friends with your local professional trade suppliers- it's time well spent!

Phil

HoustonRemodeler
Re: Bath drain size

Drain pipes are measured in nominal sizes not actual sizes. Take the pipe to a plumbing store and they will tell you what you have.

I'd be willing to bet its 1.5 inches

Mastercarpentry
Re: Bath drain size

True- Pipe size is "nominal" but usually the measurement you see is so close to a nominal size that you will know what you've got. Taking a sample along to match is always a good idea with anything as it avoids the chance of at least some potential mistakes!

And a hint for the more advanced DIY'ers:

Pipe is measured by inside diameter, tubing is measured by outside diameter, so look for the name and that will tell you where to measure.

Phil

bill
Re: Bath drain size

Drain and water pipes are always measured on the inside diameter. until you get to 12 inch pipe then on the outside diameter.

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