Active job

Need architecture's help to get consent

We want to replace our bath with a toilet, so I sent an email to the BCC department of WCC and ask do we need building consent for this job. I've got a reply says as I'm not going to add more waste water pile to my property, I don't need building consent. But because the waste pipe for bath is normally (40mm), and waste water pipe for toilet is 100mm, therefore, they still recommended my to get a building consent for this job because it's cheap and quick to do, normally they can issue the consent within 1 day. Therefore, we need an architect's help to draw a pic and get building consent. Please let me know if you have time to help us out. Cheers Edward Sun