A wide, gently rounded helical stairs can add grace and beauty to a significant room that's often under valued - the entrance hall/stairs hall.
A moderate increase in hazard may arise and may be limited due to both ends of the treads being able to accommodate a footfall
This is a stairs perhaps 1200-1500 wide, with 250-350mm treads, 150mm risers and a length of 4 metres.
With the wide steps and gentle slope, its geometry is more suited to that of a public staircase.
This gently sloping piece of winderment [sic] is probably not what you had in mind.
A word of caution.
From TDG K
http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,1651,en.pdf
1.1.6 The varying tread width of a tapered step
can cause people to misjudge distances and can lead
to falls. For this reason, the use of tapered steps
should be avoided. If it is necessary to use them,
they should preferably be situated at the bottom of
the stairs.
Public stairs should not contain tapered steps.
Where consecutive treads are used, a uniform going
should be maintained. For tapered treads, the going
should conform with par. 1.1.4 when measured as
follows
(a) if the flight is narrower than 900 mm,
measured in the middle, and
(b) if the flight is 900 mm or wider, measured 270
mm from each side.
In addition, the going at the narrow end should be a
minimum of 75 mm.
====================================
Sheltered housing suppliers have banned even tapered steps.
Using a helical stairs as the only stairs escape from the upper floors may give rise to problems with safety in use, your insurance, future letting or eventual sell-on.
I recently saw the indent of a lady's head on a plasterboard parition where she'd fallen on a tapered tread from an attic conversion access stairs - luckily she'd fallen near the bottom - she broke her wrist in the fall.
FWIW
ONQ.
[broken link removed]