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Insights · UK commercial rooftop PV

Clear guides for the roofs that matter.

Grouped by why you arrived — compliance deadlines, timing triggers, checking the numbers, and working at portfolio scale.

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Compliance & deadlines

UK energy compliance deadlines

ESOS progress updates, Welsh public sector net zero 2030, and PSDS Phase 4 (heat capital; portal closed) — dates, thresholds, and links to free official guidance.

See the deadlines →

Timing & triggers

Solar and roof replacement

Re-roofing and rooftop solar share access, fixings and structural allowance — why the decision is cheapest at replacement, and locked once the new roof is on.

See why sequence matters →

Checking the numbers · Planned

Reading an installer proposal

What to check when a quote arrives — yield assumptions, capex basis, tariff, and self-consumption — before you treat the headline payback as a decision.

Planned

Working at portfolio scale

Ranking an estate

  • Yield
  • Capex
  • Tariff
  • Self-consumption
  • Financial

You cannot rank roofs from thirty installer proposals — each uses its own yield, capex and tariff. Comparison needs identical assumptions on every building; the ranking is the product.

See why ranking is the product →

Start here

Popular guides

Six places to begin if you are new to commercial solar feasibility.

Uncategorised

What a feasibility study is

What it covers, what it is not, and who commissions one.

Uncategorised

What a study costs in the UK

Fixed fees, what drives price, and what you should expect to pay.

Uncategorised

Why independence matters

What changes when nobody is paid to say yes - incentives, assumptions, and the park verdict.

Checking the numbers

Study vs installer quote

Why a quote is not a decision document - and when each is useful.

Checking the numbers

Is commercial solar worth it?

When UK rooftops stack up - and when they do not - before you spend on surveys.

Checking the numbers

Commercial solar payback

How UK rooftop payback is calculated, and what moves the number.

Compliance & deadlines

What forces the decision

Regulation with dates — the UK obligations that put a deadline on your roofs.

In this section

Timing & triggers

When the decision is cheapest

Moments when the solar case is reset or locked — roof replacement, load change, and other triggers.

In this section

Checking the numbers

What the figures depend on

How to test payback, yield, and installer proposals — and what moves the numbers.

In this section

Working at portfolio scale

Many roofs, one order

Ranking an estate under identical assumptions — the comparison problem, not thirty separate studies.

In this section

Uncategorised

Also in the library

Guides that do not yet map to an arrival category — process, engineering, and building-type pages.

In this section

One roof, or the whole estate.

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