In order to access the upper floor your new spiral
staircase will either pass through an existing well
opening in that floor or you will need to form a new
one.
In either
case two key dimensions will be used to
specify what staircase components you require.
The instructions opposite explain how to take these
two critical measurements, If a new well opening needs to be formed
you will need to consult a qualified builder.
Firstly measure the width and depth of the opening as shown. We
offer two diameters of spiral stairs, 1400mm and 1600mm. (Now
1200mm Also)
Your well opening will need to be a minimum of
50mm larger in both directions ie. 1450mm x 1450mm minimum for a
1400mm diameter flight).
It may be that you will need to extend your current well Opening.
Secondly measure the floor to floor height that the staircase needs
to rise, this is known as the total rise of the flight be careful
to measure to the finished floor of the upper floor as you will
want the landing platform to sit flush with any floor covering
you may be intending to use . You now have all of the measurements
you need to work out your component requirements.
Treads
and Rises
The next step in working out your component requirements is to decide
how many treads you require (this is done by deciding on a quantity
of treads that gives a suitable individual rise).
Each tread/Landing platform can be adjusted to give an individual
rise of between 200 and 230 mm the maximum rise height allowed by
UK building regulations is 220mm.
Ideally you would want to stay between 200 and 210mm to build a flight
that is most comfortable in use.
To work out the number of rises needed, take your total rise measurement
and try first dividing it by 13 rises, a common number for UK staircases.
This calculation will give you the individual rise which needs to
fall between 200 and 220mm . If it does not then adjust the number
of rises until it does.
You may well find that there is more than one possible solution, ie.
2600mm overall rise divided by 13 rises = individual rise of 200mm,
or the same 2600mm overall rise divided by 12 rises = individual rise
of 216.6mm.
Both are acceptable falling between 200 and 220mm however a rise of
200mm is far more comfortable and would be the preferred solution
in this instance.
Once you have calculated the number of rises that suits your situation
best then you will know how many treads you require. This is one less
than the number of rises as the last rise is accomplished by the landing
platform. So for a 13 rise flight you will need 12 treads plus a landing
platform.
Access
to the first Tread
The final step before making a list of component codes required
Is to check that the first tread will be in a position where access
to it is unimpeded.
Use the drawings below to help. These spiral staircases can he installed
clockwise or anti-clockwise, however this will have some bearing
on the entry point.
Start from the landing platform at the top and count hack down the
flight the relevant number of treads to see where the entry point
is. Make sure that the entry is clear and unimpeded. If it is not
you have 3 ways of altering the situation.
1. Change the position of the landing platform. This is obviously
easier where a round well opening is being used as more flexibility
is available. With a square platform you will have only 4 options
here.
2. Consider installing the staircase anti-clockwise instead. This
will usually alter the entry point.
3. You may be able to adjust the number of rises (remember we said
there is often more than one solution to this number) which will
again alter the entry point.
Using one or more of these methods it is normally possible to work
out a solution.
Once you have finalised the number of treads and the configuration
of the staircase you are ready to specify your components.
Clockwise
layout
Anti-clockwise
layout
The Stair Select System
The Stair Select is a system of standard stocked components that
can be used to complete your installation.
Each stair consists of a maximum of 3 product codes with additional
landing balustrading components available.
Primary Pack
Contains virtually everything required to build your flight including
the centre post. Balustrading for the stairs and balustrading for
the landing platform and 11or 12 treads. All orders will require
a Primary Pack. Tread Pack
The tread pack is an optional item which contains 1 additional tread
with its balustrading. It is used to increase the height of a flight
where the standard 11 or 12 treads in the Primary Pack cannot reach
high enough, Up to 2 extra Tread Packs can he used with a standard
Primary Pack. Landing Pack
Contains a landing platform to complete your flight to suit either
a round or square or rectangular well opening. The Landing Pack
is ordered separately to suit the shape of well opening you are
using. All orders require a Landing pack.
Specifying your components
1. You will always require 1 Primary pack. Select the correct diameter
and model type for your requirements from the list .
2. You will always require 1 Landing pack. Again select the correct
diameter and model type for your requirements. This time you also
need to select either a Round or a Flat landing to suit your well
opening shape.
3. With the Landing and Primary Pack you have a total of 12 rises.
The last step is to add in the relevant number of additional Tread
packs. So for a 14 rise Flight you will need 2 additional Tread
Packs in the correct diameter and model.
4. Finally specify the landing components required using the final
section of the Installation Instructions to decide what you need.
Building Regulations
Building Regulations make specifications regarding 3 key areas relating
to spiral staircases.
Individual Riser Height
UK Building Regulations require that each individual rise must be
of equal height and fall within 170mm to 220mm.
Clear Width
UK Building Regulations require a minimum Clear Width on each tread
of 600mm for staircases serving one room only. These spirals are
available in 2 diameters, 1400mm and 1600mm with clear widths of
607 and 707mm respectively.
These
spiral staircases are not suitable for use as staircases serving
more than one room.
Riser Brackets
For stairs frequented by children, Building Regulations require
the gap between treads to be reduced to under 100mm. An optional
riser bracket is available to achieve this.
