I am wanting to finish off a bathroom in my basement. When I bought the house the builder told me that the spot had already been set up for a bathroom, and indeed there is a pipe sticking out of the concrete where the toilet will go and a 14"x14" cut in the concrete that gives access to another pipe where the bathtub will go.

My question is, are these pipes usually vented and trapped? Is there a way I can go about verifying that they are or are not vented and trapped correctly?

Thank you in advance for your help!

I am wanting to finish off a bathroom in my basement. When I bought the house the builder told me that the spot had allready been set up for a bathroom, and indeed there is a pipe sticking out of the concrete where the toilet will go and a 14"x14" cut in the concrete that gives access to another pipe where the bathtub will go.

My question is, are these pipes usually vented and trapped? Is there a way I can go about verifying that they are or are not vented and trapped correctly?

Thank you in advance for your help!
I had similar questions a few months back. What helped expediate the answers was to post a picture of all relevant aspects of your bathroom area. Luckily my roughins and vents were already down

I am wanting to finish off a bathroom in my basement. When I bought the house the builder told me that the spot had allready been set up for a bathroom, and indeed there is a pipe sticking out of the concrete where the toilet will go and a 14"x14" cut in the concrete that gives access to another pipe where the bathtub will go.

My question is, are these pipes usually vented and trapped? Is there a way I can go about verifying that they are or are not vented and trapped correctly?

Thank you in advance for your help!
If the pipe in the tub dap-out's sticking up then it's trapped. If it's horizontal in the hole it's not. As a rule the plumber does not run a vent from the basement out the roof since he isn't installing a basement bath but just leaving you a rough.
Most bathroom groups are roughed in like this.
Toilet connects to sewer main. The toilet wet vents through the lavatory vent. Lavatory connects to toilet drain and runs a vent out the roof or revents back into a dry vent in the attic off the top the stubout tee. The tub/shower connects to the lavatory drain and is wet vented by it. This is a normal rough in and is acceptable both by local and state codes,( unless local codes call for individual vents) but also The Standard Plumbing Code Book. Best of luck, Tom