- Project plans
- Project activities
- Legislation and standards
- Industry context
Last edited 31 Dec 2015
Alternating tread stair
Approved document K, Protection from falling, collision and impact, defines an alternating tread stair as:
In dwellings, alternating tread stairs may only be used in loft conversions where there is not enough space for conventional stairs and where the stair is for access to only one habitable room and, if desired, a bathroom and/or a WC (although this must not be the only WC in the dwelling).
Alternating tread stairs should:
- Make alternating steps uniform with parallel nosings.
- Have slip-resistant surfaces on treads.
- Should be constructed so that a 100mm diameter sphere cannot pass through the open risers.
- Provide a minimum clear headroom of 2m.
- Have tread sizes over the wider part of the step in line with the table below, and should comply with the diagram below.
 Related articles on Designing Buildings Wiki
Featured articles and news
New BRE book considers the progression from project-based knowledge creation to whole-life urban knowledge management.
This CIOB article explores the concept of value in building design and construction.
BREEAM and Measurabl announce integration to improve the financial performance of commercial real estate.
Rogers Stirk Harbour + Partners' release new images of soon-to-open 3WTC tower in New York.
A document can be called a bond or a guarantee. Does the name matter and what is the difference between them?
New briefing note is launched focusing on increasing knowledge of housing that promotes health and wellbeing.
Arbitration is a private, contractual form of dispute resolution used in the construction industry.
The European Parliament has approved a revised Energy Performance of Buildings directive.
One in six MPs supports the ring-fencing of retentions as proposed in the 'Aldous Bill'.
A stakeholder is anyone who has an interest in the process or outcome of a construction project.
BRE launches online self-assessment tool for ethical labour sourcing.