Head height for staircase

[5125andrew]

I have an existing staircase from the 1st to the 2nd floor which I want to alter. In order to create more space on the 1st floor for an en suite I want to install a winder staircase like this one -

http://www.staircases.org/Assets/staircase_layouts/SW3W36N3D.pdf

What I am struggling with is how to assess the head height required and how much this will intrude into the room above. I want to minimise this as it is an eaves bedroom and already quite small. I know building regs require 2m clearance from the stair slope but I am having trouble visualising this. Can anyone help?

thanks

 

[chappers]

you need to count up each riser to find the height at each tread.
I use these guys all the time go back to their website and find the plan drawing for this stair.
In this example the total rise is 2.6m for your stair it may be different each rise is therefore 200mm and each going in this case is 223mm.
So here goes.

At the nosing on tread 1 the height will be 200mm at the point where this will be in you room measure up 200mm and then check you have 2m clear above.
Then measure back 900mm ( this is point of intersection between dimensions A and B on their drawing) at this point you will have gon up 2 rises or 400mm mark this point measure up 400mm and make sure you again have 2m clearance above.
Then measure across the wall dimension B in this case 1779mm (this is the intersection of dimensions B and C on their drawing) from a/b you have gone up another 3 rises or 5 rises in total or 1000mm from the floor height so you should therefore have 3m clear from the floor.
Dimension cis 2237.5 and is a total of 8 risesso measure this length and at that point the mark it off at the floor height above drw aline fom 1000mm above floor to this point and that is the line of your stairs make sure you have 2m clearance above this line.
Hope that helps.
Remember though this is only clearance around the perimiter take into account the width of the stairs alsoas there may be some other obstruction above.
If you are not confident doing this yourself then get a local joiner out to measure up and sort a staircase out for you.
You will have to substitute the measurements they give you when you give them your finished floor heights.