System build-up evidence review banner — layered build-up aligned against a technical section drawing

Evidence area

Is the proposed build-up the one that was actually tested?

Most build-up evidence questions come down to one comparison: the configuration that was tested, certified, classified or declared, against the configuration being proposed.

The Bench puts the two side by side — layer by layer, fixing by fixing — and sets out in writing where they match and where they do not.

Independent evidence review. Not certification, Building Control or design sign-off.

The questions that usually arrive with a build-up query

Is this the tested build-up?

The documents describe a configuration, and someone wants confirmation the project build-up is the same one.

Does one change break the evidence?

A layer, thickness, fixing or substrate has changed, and the question is whether the evidence still applies.

Which document covers the whole assembly?

Each product has paperwork, but nothing obviously covers the build-up as a complete system.

What do we need to show for this exact configuration?

The project needs an evidence position for the build-up as proposed — not for the products in isolation.

Galvanised steel U channel profile
Galvanised U channel
Galvanised steel top hat rail profile
Top hat rail
Galvanised steel frame at 600mm centres
Framing at 600mm centres
Board fixing detail with screw and washer into a galvanised profile
Board fixing detail

The paperwork behind a build-up question

Every enquiry is different, and you do not need a complete set before getting in touch — send what you have. These are the documents that usually matter:

  • Test, classification or assessment reports for the build-up
  • Declarations of performance and data sheets for each layer
  • Drawings of the proposed build-up, with thicknesses and fixings
  • Installation guidance for the system
  • Any certificates or third-party assessments held for the assembly
  • The question as raised — the email, comment or specification query

Where build-up evidence usually falls short

A layer thickness or density has changed

The proposed build-up uses a different thickness or grade than the documented configuration.

The fixings differ

Fixing type, centres or penetration depth on the project do not match what sits behind the evidence.

A 'minor' substitution falls outside the scope

One swapped component takes the assembly outside what was tested, certified or declared.

Product documents are presented as assembly evidence

Individual data sheets are stacked up as if they proved the performance of the complete build-up.

A written build-up comparison you can use

The Bench compares the documented build-up with the proposed build-up, and puts the position in writing.

  • Compare the tested, certified or declared build-up with the proposed one, layer by layer
  • Identify which differences are likely to matter for the question being asked
  • Separate product evidence from assembly evidence
  • Produce a gap register of missing, unclear or non-matching evidence
  • Provide a written summary you can use with the project team

The output is written — a review note, clarification note, gap register or evidence summary you can use with the project team. We quote before any written work starts.

Clear about the limits of the review

The Bench reviews evidence and gives written guidance. For system build-ups in particular, the limits matter:

  • Certification, testing or classification of the build-up
  • Building Control or other statutory sign-off
  • Fire engineering or structural judgement on the build-up
  • Design responsibility for the build-up or its details

Those decisions remain with the appointed competent person or organisation for the project. Our written review is there to support them, not replace them.

Product knowledge that may relate to this evidence area

Where a product question sits behind this evidence area, the product knowledge pages set out the typical questions and the evidence commonly reviewed:

Product logos identify the product areas our evidence records cover. They do not imply certification, approval, endorsement or guaranteed acceptance of any product or build-up.

Build-up evidence question holding up the job?

Send the question, the proposed build-up and the documents you already have. No charge to submit an enquiry — we quote before any written work starts.