mike <miken...@yahoo.com>

Are there any situations where it's acceptable to use a bottle trap
with a 38mm seal on a kitchen sink or do Building Regs always require
a 76mm seal?

Also, what's a "half trap"?

http://www.toolstation.com/shop/Plumbing/Traps+Waste/Appliance+Half+T...

Isn't it either a trap or just a bit of pipe?