Supplier Code of Conduct

Version 1.0 · Effective 15 May 2026

1. Who this code applies to

This code applies to every supplier, contractor, consultant, agency, and other business partner that we engage with directly (a “Supplier”), and to all of their employees, workers, agency labour, and sub-contractors. Acceptance of this code is a condition of doing business with Atreeum.

Where we say “you” in the rest of this document, we mean the Supplier and everyone working for or on behalf of the Supplier.

2. Our core principles

The labour standards in this code are based on the Ethical Trading Initiative Base Code, which itself draws on the International Labour Organization conventions. They are the floor, not the ceiling.

1. Employment is freely chosen There is no forced, bonded, indentured, trafficked, or involuntary prison labour anywhere in your operations. Workers are not required to lodge deposits or identity papers with you. They are free to leave their employment after reasonable notice.
2. Freedom of association is respected Workers have the right to join or form trade unions of their own choosing and to bargain collectively. You do not interfere with this right. Where law restricts it, you facilitate equivalent means of independent and free worker representation.
3. Working conditions are safe and hygienic You provide a safe and clean working environment with the necessary equipment and training to perform the work. You comply with applicable health and safety law and take reasonable steps to prevent accidents and injury.
4. Child labour shall not be used You do not employ anyone below the legal minimum age for work, which in the United Kingdom is 13 for light work and 16 for full employment. You do not use children of any age in hazardous work. If existing child labour is found in your supply chain, you remediate the situation in the child's interests.
5. Living wages are paid Wages and benefits meet at least national legal standards or industry benchmarks, whichever is higher. In the United Kingdom we expect you to pay at or above the Real Living Wage rate published by the Living Wage Foundation, not merely the National Minimum Wage. Deductions from wages for disciplinary measures are not permitted.
6. Working hours are not excessive Working hours comply with national law and industry benchmarks, whichever offers greater protection. You will not require workers to work more than 48 hours per week on a regular basis, and overtime is voluntary, compensated, and not excessive.
7. No discrimination is practised There is no discrimination in hiring, compensation, training, promotion, termination, or retirement based on race, caste, national origin, religion, age, disability, gender, marital status, sexual orientation, union membership, or political affiliation.
8. Regular employment is provided Work performed is on the basis of a recognised employment relationship established through national law and practice. You do not use labour-only contracting, sub-contracting, or false self-employment to avoid obligations to workers.
9. No harsh or inhumane treatment Physical abuse, threats of physical abuse, sexual or other harassment, verbal abuse, or other forms of intimidation are prohibited.

3. Modern slavery and human trafficking

You confirm that:

• You comply with the UK Modern Slavery Act 2015 and equivalent legislation in any jurisdiction where you operate.
• You do not, and you have taken reasonable steps to ensure that your own suppliers do not, engage in any form of slavery, servitude, forced or compulsory labour, or human trafficking.
• If you are required to publish a statement under section 54 of the Modern Slavery Act 2015 (turnover £36m or more), you have done so and will provide a copy to us on request.
• If you become aware of modern slavery or trafficking in your operations or your supply chain, you will tell us within 5 working days of discovery.

You can read our own Modern Slavery Statement at atreeum.co.uk/modern-slavery.html.

4. Sector-specific requirements

Atreeum sources from sectors that carry meaningful additional risks. Where the categories below apply to you, additional standards apply on top of the core principles in section 2.

4.1 Solar photovoltaic and inverter suppliers

• Provide upstream traceability through the Solar Stewardship Initiative (SSI) certification, the SEIA Solar Supply Chain Traceability Protocol, or an equivalent independently-audited scheme acceptable to us.
• Disclose the country of polysilicon, ingot, wafer, cell, and module manufacture for each product line we purchase.
• Permit independent third-party audits of the upstream supply chain for products supplied to us.

4.2 Battery storage and electric vehicle suppliers

If you supply battery cells, packs, modules, EVs, or EV-charging equipment to Atreeum, you must:

• Provide due diligence on cobalt, lithium, nickel, and graphite supply chains aligned with the Initiative for Responsible Mining Assurance (IRMA) standard, the OECD Due Diligence Guidance for Responsible Supply Chains of Minerals from Conflict-Affected and High-Risk Areas, or an equivalent scheme acceptable to us.
• Disclose the country of mining and refining for the principal battery minerals in the products supplied to us.
• Demonstrate that no products supplied to us contain cobalt sourced through artisanal mining in the Democratic Republic of the Congo without IRMA or equivalent third-party assurance.

4.3 Off-site and modular manufacturing partners

If you manufacture homes, pods, panels, or other significant components for Atreeum, you must:

• Hold a current Gangmasters and Labour Abuse Authority (GLAA) licence where required by UK law, or its equivalent in your jurisdiction.
• Directly employ the majority of your factory-floor workforce. We expect agency or temporary labour to make up no more than 20% of your workforce on the days our products are being made, except where a written exception has been agreed with us in advance.
• Provide on request a copy of your right-to-work checks and your most recent factory health-and-safety audit.
• Permit Atreeum to visit and audit your manufacturing site with reasonable notice.

4.4 Site contractors and groundworks

If you carry out works on an Atreeum village site, you must:

• Comply with the Construction (Design and Management) Regulations 2015 (CDM 2015) and all relevant health and safety legislation.
• Conduct right-to-work checks on every person, including subcontractor labour, before they begin work on site.
• Ensure that any labour-supply agencies you use are GLAA-licensed.
• Notify us in writing of any subcontractor before they are engaged on an Atreeum site. The same standards in this code flow through to them.

4.5 Service and maintenance contractors at operational villages

If you provide cleaning, landscaping, maintenance, or similar services at a completed Atreeum village, you must:

• Hold a current GLAA licence where applicable.
• Pay at or above the Real Living Wage to every worker performing services at our villages.
• Recruit ethically: charge no recruitment fees to workers and provide written employment contracts in a language each worker understands.

5. Business ethics

5.1 Anti-bribery and anti-corruption

You comply with the UK Bribery Act 2010 and equivalent legislation in any jurisdiction where you operate. You do not offer, give, request, or accept any bribe, kickback, or improper payment, whether to or from a public official or a private party. You do not engage in facilitation payments. You keep accurate books and records.

5.2 Conflicts of interest

You disclose to us in advance any actual, potential, or perceived conflict of interest involving Atreeum employees, contractors, directors, or members of their immediate families.

5.3 Fair competition

You comply with applicable competition and anti-trust law. You do not enter into agreements with competitors that would fix prices, allocate markets, or rig bids.

5.4 Sanctions and export controls

You comply with the UK and equivalent international sanctions regimes and export controls applicable to the goods, services, software, and technology you supply.

5.5 Confidentiality and data protection

You protect any confidential information of Atreeum or of our seeders and customers that comes into your possession. If you handle personal data on our behalf you act as our data processor, comply with the UK GDPR and the Data Protection Act 2018, and enter into appropriate written data-processing terms with us. Our Privacy Notice is at atreeum.co.uk/privacy.html.

6. Environment and community

6.1 Environmental compliance

You comply with all applicable environmental legislation, hold any necessary permits and licences, and operate them within the required conditions. You take reasonable steps to reduce the environmental impact of the goods and services you supply to us.

6.2 Climate and carbon

Atreeum is building energy-positive housing on net-zero principles. We expect significant suppliers (those representing more than 5% of our annual spend) to be able to provide carbon-footprint information for products supplied to us, and to engage constructively with us on reducing it over time.

6.3 Local community

Where work is carried out in or near an Atreeum village or supplier facility, you respect the surrounding community, manage noise, dust, traffic, and other impacts responsibly, and engage with local authorities and residents in good faith.

7. Sub-contracting and supply chain

You take reasonable steps to ensure that your own suppliers and sub-contractors comply with standards equivalent to those in this code. Specifically:

• You include compliance obligations in your contracts with your sub-contractors that are no less stringent than this code.
• You exercise risk-based due diligence on those sub-contractors who present higher modern-slavery, labour, or environmental risk.
• You do not sub-contract any part of the work you perform for Atreeum to a third party without our prior written consent where the work involves on-site presence at an Atreeum village or direct contribution to the manufacture of an Atreeum home.

8. Monitoring, audit, and reporting

8.1 Self-assessment

On request, you will complete and return to us a self-assessment questionnaire confirming your compliance with this code and providing supporting evidence.

8.2 Right to audit

We reserve the right, on reasonable notice (normally not less than 5 working days, but immediately in the case of suspected serious breach), to audit your compliance with this code. We may carry out the audit ourselves, or commission an independent third party to do so. You will provide reasonable access and cooperation. We pay our own audit costs unless the audit identifies a material breach, in which case you pay our reasonable costs.

8.3 Reporting concerns

If you become aware of a breach of this code (in your own operations or in your supply chain) you will:

• Tell us in writing within 5 working days of discovery.
• Propose a remediation plan with a timeline.
• Implement the agreed plan and report on progress.

Anyone (a Supplier's employee, an Atreeum employee, a member of the public, a seeder) can report a suspected breach of this code in confidence by emailing hello@atreeum.co.uk with “Supplier Code” in the subject line. We do not retaliate against people who report in good faith and we keep the reporter's identity confidential to the extent we are lawfully able.

9. Consequences of breach

We expect to handle most breaches through dialogue and remediation. Where a breach is identified, our normal approach is:

1. Discuss the issue with you and agree a written remediation plan with a clear timeline.
2. Monitor your delivery of the plan. Continue to do business with you while it is being delivered, subject to the seriousness of the breach.
3. If the plan is not delivered on time, or if a further breach occurs, suspend new orders and re-evaluate the relationship.
4. Terminate the relationship in cases of serious or repeated breach, of breach involving forced or child labour, or of failure to engage with remediation.

We retain the right to immediately suspend or terminate any contract for material breach of this code, in particular any breach involving modern slavery, child labour, bribery, or sanctions.

10. Updates to this code

We will review and may update this code from time to time, in particular as our supply chains expand and as our understanding of the risks improves. We will notify Suppliers of material changes in writing and the current version will always be at atreeum.co.uk/supplier-code.html. The version that applies to a given contract is the version current at the date the contract was signed, unless we have agreed an update in writing.