Update Our Hot State member checks were launched a few weeks ago and have garnered much interest, however one question that keeps being asked is what boards are used and what ratings in terms of time are available so we thought we'd publish an abridged table showing the solutions available.
We have generated a quick spreadsheet demonstrating the publicly available data we have access to and have listed above to illustrate.
The tool incorporates data available from James Hardie Fermacell boards, and Knauf boards
We have applied a ‘Filter’ and given some brief instructions on how to use / filter using fire rating as an example.
Our data is ‘different’ to others / board manufacturers data as our definition of fire rating integrity is the point at which the ‘hot flange’ reaches the critical temperature – for example the 1st two rows state 39 and 46 minutes and the very last states 63 minutes. Other rows do state 30, 60, 90 minutes and is a foible of the data available and our requirements.
Traditional definitions of ‘Fire Rating’ and ‘Integrity’ in terms of fire relate to measures like:
How long ‘till flame licks through the ‘cold side’ of the wall
How long ‘till a cotton swab instantaneously catches fire due to heat radiating from the wall assembly
All great definitions, however, we are concerned with the point at which the wall stud can no longer carry the applied load defined by the point at which the hot flange reaches the critical temperature. (This temperature figure is NOT listed in the table attached).
All of the above is based on ‘dry lining studs’ which is critical as the larger / heavier / greater cross-sectional area the longer the fire rating – by our definition – as the stud wicks more heat from the boards and thus they can resist the fire for longer.
This then means that we can calculate the stud capacity for any of the wall systems using ANY of the studs in our database – including YOUR (prefererred manufacturer's) STUDS.
This has nothing to do with acoustic or thermal performance – though there is data on whether the ‘system’ has insulation between the studs which does have an impact on acoustics and thermal performance in terms of Part L. This however leads to a much more detailed piece of work around standardisation of systems and studs such as I am trying to carry out through BSi CB/301, and I s a much, much longer email
Using our plug in for Tedds and linking to Tekla Structures for example users can:
Design LGS portal frames in moments – these are lighter than traditional HR steel portals, but only at their most effective upto 20m span, when HR frames work best anyway.
Recently, MMCEngineer Ltd wrote and had approved by the SCI on behalf of NHBC a Stage 1 LGS manual for Birkbeck Structures which covers up to Fifteen Stories which is far more, using their concrete floors, than a load bearing test rig can apply load to simulate
MMCEngineer founder and Engineer Stephen Napper CEng commented
"Our methodology will prove invaluable to their clients submitting designs to the BSA. When they are asked to demonstrate that they can provide fire safe designs at these heights and loads. they will have something accurate to hand."
Designs using these tools relative to the ambient state checks
Selling copies of the design guide which includes:
worked examples to hot state checks,
zero load factor examples and
ambient state checks for the same members
Indicative floor joist designs using various floor loads to illustrate real world loads
If you'd like a copy of the design guide please use the Contact Form at the bottom of the page or use the payment link or request an invoice. We also have a FAQ that answers the most common questions people have asked us about the work.
In time our sister company, Modern Engineered Software Solutions Ltd will be adding the calculations to the plug in’s available for Tedds. This update will be released in due time.
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