An open method for sustainable digital decisions
Digital decisions can lock in energy demand, emissions, cost, dependencies and hardware consequences years before those outcomes become visible in reporting.
SDAF provides an open, evidence-governed method for comparing functionally equivalent options and creating a transparent, reviewable sustainable digital architecture decision.
Open, vendor-neutral and designed to complement—not replace—established standards and specialist methods.
Questions SDAF helps you answer
Every important technology decision creates consequences. SDAF gives teams a shared way to understand, evaluate and decide before those consequences become difficult to reverse.
Are the alternatives functionally equivalent?
Consider energy, carbon, circularity, lifecycle and cost.
Keep sources, assumptions and evidence gaps visible.
Assess evidence quality and confidence separately from impact.
Cost, risk, performance and sustainability may align—or conflict. An apparent improvement may defer a cost, transfer an impact or create a new dependency.
Create a reviewable decision record before making the commitment.
See SDAF in action
SDAF Studio provides a guided workspace for comparing options, recording evidence and assumptions, examining environmental and financial trade-offs, and preparing a decision for accountable review.
The vision
Why this matters now
AI, cloud platforms and data-intensive services are increasing demand for compute, energy, water and hardware. At the same time, organizations face greater scrutiny over environmental claims, investment choices and supply-chain impacts.
Architecture choices increasingly influence energy demand, infrastructure scale and hardware turnover.
Decision owners need to distinguish measured data from supplier claims, benchmarks, assumptions and unknowns.
The best opportunity to avoid impact is before architecture, procurement and lifecycle choices become difficult to reverse.
What SDAF means
SDAF is an open, vendor-neutral reference framework for making evidence-based, transparent and defensible sustainability decisions about digital systems.
Architecture, procurement and lifecycle decisions can lock in environmental consequences long before they appear in a sustainability report. SDAF brings those consequences into the decision while there is still time to change the outcome.
It provides a structured, repeatable route from requirements and comparable evidence to a traceable, reviewable decision. Sustainability becomes part of architecture, procurement and lifecycle choices—not only something reported afterwards.
Leaders, architects, sustainability and finance teams, procurement, engineering, operations, risk, governance and assurance can use the same decision structure across projects, services, portfolios and supply chains.
SDAF does not prescribe a technology, supplier or calculation tool. It does not replace legislation, standards, certification schemes or specialist methods; it helps teams apply them coherently within a decision.
Who uses SDAF
SDAF gives technical, sustainability, commercial and governance stakeholders a shared basis for understanding the same decision.
Compare strategic technology options and make sustainability part of architecture governance.
Embed functional equivalence, boundaries and environmental criteria while solutions can still change.
Improve evidence quality, methodological consistency and the traceability of environmental claims.
Evaluate suppliers, acquisition routes, lifecycle effects, cost and retention choices consistently.
Understand trade-offs, uncertainty and approval conditions before committing investment.
Enterprise integration
SDAF does not require sustainability to initiate a decision or create a parallel approval process. It brings environmental, financial, lifecycle and evidence consequences into the forums where application, architecture, cost, procurement and asset decisions already happen.
SDAF can also preserve material operational, dependency, knowledge and workforce consequences where they affect the durability or governability of an architecture decision. These remain distinct from environmental results and are referred to the appropriate specialist process.
Sustainability does not need to initiate or dominate every technology decision. Environmental and lifecycle consequences should remain visible alongside cost, risk, resilience, performance and operational considerations wherever decisions are already being made.
Why SDAF is different
SDAF complements accounting and reporting approaches by bringing comparable evidence into the architecture decision itself.
| A common sustainability assessment | SDAF |
|---|---|
| Often applied after decisions | Informs decisions before impacts are locked in |
| Individual environmental metrics | Energy, carbon, lifecycle, circularity and cost |
| Comparability may be unclear | Functional equivalence and boundaries defined first |
| Assumptions can disappear into results | Evidence, assumptions, uncertainty and confidence remain visible |
| Point-in-time recommendation | Governed path from decision framing to assurance |
Start with the method
It makes the logic behind a sustainability claim visible: what is being compared, what is inside the boundary, which evidence supports the result and how uncertainty affects confidence.
State the intended outcome, functional unit, reference flow, system boundary and equivalent service before comparing options.
Comparable by designConsider operational energy, carbon, lifecycle effects, circularity and cost across the parts of the system that the decision can influence.
Lifecycle visibilityKeep actual data, derived values, benchmarks, assumptions and unknowns distinct so the result carries an honest level of confidence.
Evidence before claimsThe framework
A beginner can follow the sequence from the initial question to an assured recommendation. Experienced practitioners can go deeper into the eight-part framework, evidence trail and methodological controls.
Define the decision, purpose, ownership and sustainability intent.
Set the functional unit, boundaries, reference flow and equivalent service.
Compare energy, carbon, lifecycle, circularity and value using traceable inputs.
Translate the evidence into an owned technical recommendation and conditions.
Challenge confidence, sensitivity, completeness and reproducibility before release.
Purpose, principles, terminology, applicability and normative structure.
The controlled five-phase assessment lifecycle from Orient to Assure.
Boundaries, evidence quality, methods, uncertainty, confidence and traceability.
Evidence sufficiency, stability and the defensible decision record.
Lifecycle burdens and circularity benefits without double counting.
Oversight, independence, conformance and assurance requirements.
Roles, systems, controls, capability and operating cadence.
Controlled evidence exchange across organizations and methods.
Explore SDAF
The homepage is your orientation. Go deeper only where it is useful: understand the origin, apply the method, browse the evidence base or follow the latest thinking.
See the phases, evidence rules and decision architecture.
Explore the method → ApplicationBuild an evidence-backed, reviewable decision record.
Open Studio → LibraryFind publications, worked examples, public methods and standards.
Open the library → InsightsRead exploratory articles without changing the normative method.
Read the latest insight → OriginUnderstand the observations, questions and accountable human process behind the framework.
Read the journey → AdoptionIntegrate SDAF into the governance and operating model you already have.
Open the Playbook →Open participation
SDAF is intended to provide neutral ground for people and organisations that influence digital architecture decisions. Participation is open; endorsement, certification and preferential status are not implied.
SDAF welcomes participation from practitioners, decision owners, technology and service providers, operators, researchers, sustainability specialists, assurance organisations, customers and standards bodies.
Participants are invited to test SDAF against real decisions, challenge its assumptions, propose mappings, contribute evidence models, share implementation experience and identify gaps.
Feedback and completed worked examples are especially welcome. Examples may show a successful recommendation, a conditional outcome, an inconclusive assessment or a decision not to proceed. Each can strengthen the method when its evidence, assumptions and limitations remain visible.
Open participation. Transparent contribution. Independent governance.
Use SDAF in a pilot or implementation and share what worked, what failed and what remains unclear.
Explore how measurements, estimates, telemetry, declarations or datasets can support a traceable SDAF assessment.
Share a completed assessment, decision pattern or anonymised case so others can learn from its evidence, trade-offs and outcome.
Question assumptions, identify missing perspectives and propose transparent improvements or standards mappings.
Why trust SDAF
SDAF does not ask users to accept a hidden score. The method, source material, evidence classifications, assumptions and release history can be reviewed independently.
The complete repository, supporting documents, diagrams and change history are available for review.
Browse GitHubZenodo provides the authoritative publication record and a persistent DOI for citation.
Open ZenodoGHG Protocol Scope 2 and relevant ISO lifecycle, carbon, PUE and circularity standards inform the applicable methods.
Actual, derived, benchmark, assumed and missing evidence remain distinct. Incomplete required evidence cannot support a conclusive result.
Open framework · shared progress
SDAF is intended to grow through practical use, constructive challenge and shared learning. If you apply it, find a gap, want to run a pilot, contribute evidence or explore standards alignment, your perspective is welcome.
