LearnThe Bench library
Learn holds what The Bench has published: questions worked through in full, the eight areas construction product questions usually fall into, and a dated watch on the rules behind the evidence.
It is organised by how you want to read, not by what we want to sell. There is no publishing schedule — nothing is published before its evidence is ready.
You know the topic
Go straight to an evidence area.
Each area sets out the questions that usually arrive, the documents that decide them and where the evidence tends to fall short.
You know the question, not where it belongs
Find your route.
Two kinds of published work. An Investigation puts the full evidence base to a question the industry argues about. A Bench Evidence Note works one evidence question through, end to end. The two series are numbered separately.
External Wall Design in a Changing UK Climate
Cavities are argued about in absolutes, in both directions. The review reframes the question and puts it to the evidence: when can cavity, part-cavity and cavity-free external walls perform safely and durably, and what evidence shows it. Conclusions are calibrated, and where the evidence runs out it says so.
Scope: an evidence review of wall strategies — not an assessment of any project build-up.
Why specification, exposure and maintenance matter for reactive fire-protection coatings on structural steel
R120 tells you a fire-resistance period. It does not tell you the whole evidence position. The applicable evidence also depends on the member, system build-up, environmental exposure, application and lifecycle conditions.
Scope: reactive coatings on structural steel only. The Bench and connected businesses have commercial interests in passive-fire-protection systems; the Note does not assess, compare, rank or recommend any product.
How to read separate assembly evidence where two wall constructions meet
Two wall constructions can each have sound supporting evidence. This note explains how to check whether that evidence, or other applicable information, addresses the place where they meet.
Scope: how to read separate evidence where two wall constructions meet; fire only, England and the GB product regime. The Bench and connected businesses have commercial interests in passive-fire-protection systems; the Note does not assess, compare, rank or recommend any product.
Everything listed here is live. New kinds of content are added only once something has been published.
A real technical question worked through in full — scope fixed first, calibrated conclusions, limits stated.
Live · 1 published
Cavity vs No Cavity?
One evidence question — specification, applicability and where the evidence stops — worked through end to end.
Live · 2 published
The Fire Rating Is Only the Start
What Covers the Junction?
Reports
The full published reports, with sources and confidence reasoning, as PDFs.
Live · 3 published
Cavity vs No Cavity? — External Issue 02 (PDF)
The Fire Rating Is Only the Start (PDF)
What Covers the Junction? (PDF)
The eight areas enquiries usually fall into — what gets asked, which documents decide it, where the evidence usually falls short.
Live · 8 areas
See the index below
What construction product evidence has to do, what it is declared for, and where the rules are moving — checked against primary sources, with the higher-risk building regime kept separate. England only; not legal advice.
Live · reviewed 23 September 2026
Videos
Questions talked through on camera, with the evidence in shot.
Live · 3 on this site
Cavity vs No Cavity? — technical briefing (14 min)
The Fire Rating Is Only the Start — short (65 s)
What Covers the Junction? — short film (43 s)
Each area sets out the questions that usually arrive, the documents that decide them and where the evidence tends to fall short. The related public study is listed where one exists; where none exists yet, the gap is stated.
Reaction to fire, fire resistance, classification reports and field of application — checked against the build-up actually proposed.
The Fire Rating Is Only the Start — Reactive coatings on structural steel only — not evidence for boards or any other product.
Cavity vs No Cavity? — External-wall fire pathways and assembly scope.
Declared values, U-value calculations and thermal claims — checked against the actual build-up, thickness and substrate.
Cavity vs No Cavity? — Solar gain and summer heat — climate discussion, not a U-value result.
Condensation, moisture and mould queries — the evidence and the assumptions behind it, conditions included.
Cavity vs No Cavity? — Moisture pathways and cavity functions.
Racking board evidence — test method, category, frame, fixing pattern and substrate against the project assumptions.
The Bench has not yet published a racking-specific study.
Cladding, carrier boards and external wall system evidence — checked against the project detail under scrutiny.
Cavity vs No Cavity? — The external wall cavity question, worked through in full.
The core comparison behind most evidence questions: the build-up that was tested against the build-up being proposed.
Cavity vs No Cavity? — What a wall system must do, and where its interfaces fail.
The Fire Rating Is Only the Start — Coating system build-up — reactive coatings on structural steel only.
Wall, floor and ceiling system evidence against the detail being drawn, specified or installed — junctions included.
No dedicated Bench investigation yet.
Render and brick slip systems reviewed as assemblies — carrier board included — with evidence-transfer risk flagged.
Cavity vs No Cavity? — Cavity and cavity-free assembly scope — not approval of any render or slip system.
Most construction product questions do not stall because there is no evidence. They stall because the evidence does not quite answer the project-specific question being asked. These are the gaps that come up most often, whatever the topic.
An evidence gap does not automatically mean a product or detail is unsuitable. It means the available information may not answer the project-specific question without further review, clarification or specialist input.
Each evidence area above sets out where the evidence tends to fall short for its topic. If one of these gaps is holding up your question, find your route or ask The Bench.
Send the question, the project detail and the documents you already have. No charge to submit — we quote before any written work starts.
Not sure where your question sits? Find your route ›
What helps us start
You do not need a complete set to get in touch — send what you have.