Reading the H1 report

Whether you are looking at the live result on the H1 page or the generated PDF, the same structure applies: a headline verdict, the heat-loss comparison behind it, the hard-rule checks that apply regardless, and the advisory notes that help you trust the numbers.

The headline verdict

The overall verdict is Pass or Fail. It folds together the whole-building heat-loss comparison (§2.1.2.6) and the hard rules - the glazing cap (§2.1.2.5) and the minimum construction R-values (§2.1.2.11). If any hard rule fails, the headline fails, even when the heat-loss comparison passes on its own.

The heat-loss check

This is the core of the Calculation Method: your proposed building's heat loss must not exceed the reference building's for its climate zone. Three figures tell the story:

• Proposed (HL) - your building's heat loss, from Equation 2.1.
• Reference (HL) - the reference building's heat loss, from the Table 2.1.2.7 coefficients for the zone.
• Headroom - how much room you have (proposed under reference), as a value and a percentage. Positive headroom passes; negative fails.

Expand element breakdowns to see the contribution of each element (roof, wall, floor, glazing, door, skylight) on the proposed side, and the reference bucket it is compared against.

Hard-rule checks

Some limits apply regardless of the heat-loss trade-off. Each is shown pass, fail, or not applicable:

• Glazing cap (§2.1.2.5) - wall glazing must be 40% or less of the gross wall area; above that, the Calculation Method does not apply.
• Minimum construction R-values (§2.1.2.11) - roof R2.6, wall R1.0, and other (suspended) floor R1.3.
• Heated-element minimums (§2.1.2.12) - higher minimums where an element serves a specifically heated space.

A construction can clear the heat-loss comparison and still fail a minimum, so these are surfaced separately.

Advisory notes

These never change the verdict; they help you catch a take-off that does not add up:

• Take-off reconciliation - opening-versus-element sanity checks (for example, more glazing area than wall).
• Opening R-value plausibility (Appendix D) - flags a window, door or skylight R-value that looks out of range.
• §2.1.2.13 defaults applied - where a default R-value was used because a value was not supplied (R0.18 for an opaque element, R0.15 for a window or glazed door).

Required disclosures on the report

The PDF carries an always-on disclosures strip: the framing fraction assumed, any supplied or externally-determined value, and any plausibility caution. They are the reviewer's map of what to check before certifying. A downlight derate, where one applies, shows its working in the validation-warnings section.

Project status

A project's status travels with the report:

Status	Meaning
Draft	Working state; report carries a preview watermark.
In Review	Set aside for a check; still editable, still watermarked.
Submitted	Awaiting final sign-off; report prints without the watermark.
Approved	Locked. Copy it to revise.

Review comments are not tied to a status - colleagues on a shared project can comment against elements at any time, and a submitted project stays reviewable.

Next

• How Thermly calculates compliance - the method behind the numbers.
• Generating your H1 report.