Green Building Forum - WUFI Accreditation for Bldg Regs application Tue, 19 Dec 2023 04:19:17 +0000 http://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 WUFI Accreditation for Bldg Regs application http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303531#Comment_303531 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303531#Comment_303531 Tue, 26 Sep 2023 11:21:51 +0100 fostertom
The recently revision to BS5250:2021 was intended to fix its shortcomings, with an excellent whole-building approach to all forms of moisture, in place of the simplistic/prescriptive approach of old BS5250:2002 and :2011. It allows (prefers) use of WUFI via BS 15026, explaining the limitations of the Glaser method via BS13788:2002. Yet I see that Bldg Regs Part C (still 2013 version) still requires compliance with BS5250:2002 (two versions out of date) i.e. use of Glaser method; BS 15026 isn't mentioned anywhere in the current Bldg Regs.

So can WUFI be used at all in UK Bldg Regs? It obviously has been in useful use for years, so what's the route?

And following that, what do I have to do to gain Accreditation to use my WUFI study in a Bldg Regs application? I've done the TGR 2-day course (twice actually) but that included no such certificate. I'm asking this elsewhere, but any idea here?]]> WUFI Accreditation for Bldg Regs application http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303532#Comment_303532 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303532#Comment_303532 Tue, 26 Sep 2023 16:46:38 +0100 djh
"C2. The walls, floors and roof of the building shall adequately
protect the building and people who use the building from
harmful effects caused by:
(a) ground moisture;
(b) precipitation including wind-driven spray;
(c) interstitial and surface condensation; and
(d) spillage of water from or associated with sanitary
fittings or fixed appliances."

It's the approved guidance that mentions the standard and there it's just a statement that if you follow the standard you will meet the requirement. It doesn't forbid other ways of meeting the requirement.

So there's no compulsion to meet the standard or to use it at all; you just have to demonstrate you've met the requirement. I would suggest performing a WUFI analysis and a Glaser analysis and writing up a short report that demonstrates the difference between them and why the WUFI one is more likely to be correct. I'm sure there must be published analyses of Glaser analyses producing incorrect results that you can refer to. You need to find a building inspector who's willing to accept science, or be prepared to appeal a refusal.

edit to add: a reference that may be useful is https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/815953/R1_M10_Research_Summary.pdf

and others found at https://www.gov.uk/government/publications/resistance-to-moisture-in-buildings

"The Ministry of Housing, Communities and Local Government (MHCLG) commissioned PRP to carry out this research study, entitled Research into resistance to moisture in buildings. ....

"Hygrothermal modelling should be used to assess moisture risk as advised in
BS5250 6 . The simple Glaser method is only suitable for moisture closed and
weathertight constructions, whereas dynamic hygrothermal simulation (using
software such as WUFI or Delphin) should be used for moisture open
constructions where wind driven rain or other moisture sources are present. ...."]]> WUFI Accreditation for Bldg Regs application http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303534#Comment_303534 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303534#Comment_303534 Tue, 26 Sep 2023 19:11:31 +0100 fostertom "... will meet requirements if ... in accordance with ... BS 5250:2002 and 13788:2002".

I was freaked by Bldg Insp Refusal saying "The design does not conform to the guidance of BS5250". Should have known better. Much relief - thanks.

With that, just my last para above remains:
Posted By: fostertomwhat do I have to do to gain Accreditation to use my WUFI study in a Bldg Regs application? I've done the TGR 2-day course (twice actually) but that included no such certificate. I'm asking this elsewhere, but any idea here?
]]> WUFI Accreditation for Bldg Regs application http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303552#Comment_303552 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303552#Comment_303552 Wed, 27 Sep 2023 11:45:27 +0100 Doubting_Thomas Posted By: fostertomwhat do I have to do to gain Accreditation

Are you sure there is formal accreditation? I'm sure when I looked into something similar for training 2D thermal bridging calculations (BS EN ISO 10211) it looked as though there was no accreditation body overseeing this.

The onus appeared to be on the individual to demonstrate compliance with the British Standard through their output, but not through any form of qualifications or affiliation to a trade body.

For what it's worth, TU Dublin are offering a series of online courses which I've been considering. One of these (TU5408) is in hygrothermal modelling and results in a certificate, plus it forms part of a wider MSc in Building Performance.

It's run by Joe Little so will be similar to the one you did a few years ago, but in this case has the 'weight' of a university system behind it.

https://www.tudublin.ie/study/professional-development/architecture/]]> WUFI Accreditation for Bldg Regs application http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303557#Comment_303557 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303557#Comment_303557 Wed, 27 Sep 2023 14:09:02 +0100 fostertom But I wonder how it's poss to
Posted By: Doubting_Thomasdemonstrate compliance with the British Standard through their output
when all the Standard describes, I'd guess, is that software must accurately model a list of physics parameters, and users must competently input appropriate data and interpret the results.

I expect there's a Certificate saying that the software complies, but the question is, how can any user demonstrate competence 'through their output' - who's to judge that the 'output' demonstrates competence? Surely competence has to be taken on trust, evidenced by some qualification or accreditation? Or I could have a go at impressing the Bldg Insp with my training and hours, don't know.]]> WUFI Accreditation for Bldg Regs application http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303563#Comment_303563 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303563#Comment_303563 Wed, 27 Sep 2023 20:41:58 +0100 djh Posted By: fostertomSurely competence has to be taken on trustNo the competence of the submitter is assessed by the building control officer/inspector by inspecting their work. Which is open to the situation, apparently increasingly common, where the submitter knows more than the BCO.

I could have a go at impressing the Bldg Insp with my training and hours, don't know.
Exactly. Just write the report or whatever you need to submit in a form s/he expects and put in enough working and references to demonstrate the calculations are genuine.]]> WUFI Accreditation for Bldg Regs application http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303573#Comment_303573 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303573#Comment_303573 Thu, 28 Sep 2023 09:14:31 +0100 fostertom
Last time the issue came up, I contacted several firms who advertise that they use WUFI, to see if they'd do a case study or two for a fee, and they either just said no, or explained they only used it for their own internal projects, wouldn't take the risk of offering it as a consultancy!]]> WUFI Accreditation for Bldg Regs application http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303879#Comment_303879 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303879#Comment_303879 Mon, 16 Oct 2023 11:59:33 +0100 TimSmall
At the time, I gave wufi calcs (moisture content graphs at key locations) along with a brief one paragraph summary. The local authority building inspect at the time said he was happy with it.

The same building control submission included a rear extension, which we're only just now finishing up.

A couple of weeks ago I requested a site visit for a newly constructed soakaway in the back garden. New building inspector arrived and said that they couldn't find any notes for anything to do with the loft conversion.

I couldn't find the summary paragraph, but still had the graphs, so resubmitted them last week together with a 3 page essay.

I'll let you know how I get on!]]> WUFI Accreditation for Bldg Regs application http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303896#Comment_303896 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303896#Comment_303896 Wed, 18 Oct 2023 06:35:02 +0100 cjard WUFI Accreditation for Bldg Regs application http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303899#Comment_303899 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17970&Focus=303899#Comment_303899 Wed, 18 Oct 2023 09:33:20 +0100 fostertom