Angle of lead slate

The diagram below shows a 5:12 roof pitch. From this, I've calculated the angles and included them, they are, 67.4° and 22.6°.

A soil pipe will project out through the kitchen roof, after having being brought from the 1st floor bathroom toilet and immediately through the bathroom wall which locates it within the ground floor kitchen roofspace.

I therefore require a lead slate (in grey on diagram) produced with a specific angle (in blue). This angle is between the lead slate and the attached lead pipe.

For the angle, I was thinking of 22.6° - 2.5° = 20°.

What do you think?

 

It's possible to purchase angled lead slates. For example:

http://www.hotline-chimneys.co.uk/lead-slates-angled/

However, the "best" that can be purchased off-the-shelf appears to be 45 degrees from the slate, whereas I think I would require 20 degrees from the slate. Though I know that these types of lead slate can be produced on a one-off basis, so could probably get one specially made.

What is the SVP?

 

Ok, I see what you mean.

The soil pipe comes straight out through the 1st floor bathroom wall, directly from the toilet, and emerges within the kitchen roof cavity.

The slightly less than horizontal green line is the soil pipe initially within the kitchen roof cavity then emerging from the slates and connecting up to the vertical green SVP.

 

Yes, like this.

 

This is the type of product that I need. In the one you linked the angle between the plate and the tube is 45 degrees.

However, according to my calculations, the angle between the plate and the pipe would need to be 20 degrees. It doesn't appear to be possible to purchase this off-the-shelf, so I'd have to get it made specially.

I'm wondering if I have the calculation of 20 degrees correct to take into account the fact that this pipe has to have a slight slope in it.

 

Thanks very much CraigMcK. What software package did you use to produce the diagram, I just did my original diagram in Paint.

 

Thanks for that!

Would anyone happen to know if a weathering collar would also be required to attached between the lead pipe (from the lead slate) and the attached plastic soil pipe?

http://www.screwfix.com/p/floplast-sp300-weathering-collar-black-110mm/25918

 

Thanks!