How to measure toilet outlet to soil pipe height

[Madrab]

@Mrxman .... What kind of flooring is down? If you raise the toilet up on a piece of wood the size of the pan, it never quite looks right. If the flooring allows then you could add say a 9mm piece of ply over the whole floor that'll give the height needed. Min fall of 18mm per M minimum on a soil pipe, so that equates to 5.45mm@300mm.

B.T.W. - Table 6 covers foul drains/sewers, i.e. the underground pipework.

Doc H1 Table 2 covers discharge pipes, i.e. the soil pipes

 

[Mrxman]

@Mrxman .... What kind of flooring is down? If you raise the toilet up on a piece of wood the size of the pan, it never quite looks right. If the flooring allows then you could add say a 9mm piece of ply over the whole floor that'll give the height needed. Min fall of 18mm per M minimum on a soil pipe, so that equates to 5.45mm@300mm.

B.T.W. - Table 6 covers foul drains/sewers, i.e. the underground pipework.

Doc H1 Table 2 covers discharge pipes, i.e. the soil pipes

View attachment 375478

I've given up on the plinth idea. Tested it and it didn't look great so that idea is out.
I am putting down 6 mm plywood plus some vinyl flooring which is 3.2 mm thick. There's a reason why I didn't use 9 mm ply which is to do with the steps into the bathroom and concern for potential trip hazard. I have accounted for the raised floor though and I think I'll end up with a slope of around 6-7 mm. I need to check it properly though and remove the old toilet to be absolutely certain but let's just say I am optimistic. If not I may need to look at the soil stack and see what can be done.

Thanks for info regarding the sewer pipes. I'll edit my post to avoid misleading anyone.