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Indoor Air Quality Under Building Regs Part F — 2026 Update

The CO2 thresholds in the 2026 amendment, what counts as compliance, and the in-room sensors that pass DEC audit.

Tier 1 · Best PracticeUK4.7 (64 ratings)893 learners
EF
Dr. Emma ForsbergCEng MIMechE MCIBSE

HVAC Principal — Cundall

Section 1 of 4

First principles & design

Start from the physics — the why — then the design that flows from it. First principles is the design: the judgement AI can't recite.

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The design · EngTree Engineering

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Section 2 of 4

Validation — codes & standards

The codes are the validation. Here's the chartered review, the standards cited, and the trust score that stands behind this design.

Knowledge Index™

75/100
Strongly verified
See breakdown
  • Author credentials (20%)14.0
  • Specialism match (10%)5.0
  • Validators × tier (25%)23.5
  • Standards currency (10%)0.0
  • Recency (10%)10.0
  • Field-application signal (10%)7.8
  • No dissent flag (5%)5.0
  • Jurisdictional precision (10%)10.0
  • · Author credential: CEng
  • · 1 validator
  • · Some cited standards may be superseded

EngTree's algorithmic trust score. Computed nightly from author credentials, validator chain, standards currency and recency. Higher is better.

Validators (1)

  • IM

    Prof. Ian Murray

    CEng FIMechE FCIBSE

    Verified against Approved Document F

    9 Apr 2026

Standards cited

  • Approved Document F
  • CIBSE TM40

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Section 3 of 4

Interfaces & buildability

Where the validated design meets reality — coordination, technical interfaces, construction management, and the disciplines that hand off to each other. The bit textbooks skip.

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Section 4 of 4

Delivery — on site

How it's actually built — by the trade professional who does it. Same topic, two credential chains: design ↔ delivery. EngTree Trade.

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Design → Delivery

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design_slug: iaq-building-regs-part-f-2026 · no pair wired

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Ask & discuss· Roots · 12 comments

  • James O. (Graduate Geotechnical Engineer)

    3 weeks ago

    Used the α=0.45 figure on a job in Hackney last month — bentonite-installed piles, below water table. Load test came back within 4% of predicted. The negative skin friction reminder saved us; the made ground there is recent and consolidating measurably.

    ▲ 18Reply

  • Helena V., CEng MICE

    2 weeks ago

    The end-bearing reduction in fissured zones isn't widely appreciated. We had a project at Bank station where the textbook approach would've given us 30% more capacity than the actual fissured London clay supports. Recommend adding a sketch of typical fissure mapping.

    ▲ 11Reply

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Other perspectives on this topic

Multiple creators publish takes on the same sub-topic. Different experience, different jurisdictions, different angles. All chartered-validated, all ranked by Knowledge Index.

4 of 4 perspectives