Sierra Building Services

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Sierra Building Services Limited
Last updated: 22 August 2026

Sierra Building Services Limited (“Sierra”, “we”, “us”) is the data controller for the personal information described in this policy. This page explains what we collect, why, how long we keep it and what you can do about it.

Company: Sierra Building Services Limited, registered in England & Wales, company number 08288946
Registered office: 3rd Floor Lawford House, Albert Place, London N3 1QA
Contact: info@sierrabuildingservices.co.uk

1. The information we collect

When you contact us. The enquiry form on this website asks for your name, email address, company and a description of what you need. If you email or call us instead, we hold whatever you choose to tell us. We use this to answer your enquiry and, if it turns into work, to scope and price it.

When we work for you. To produce an O&M manual or a CDM Health & Safety File we need your project material — specifications, technical submittals, commissioning records, test certificates, as-built drawings, drawing registers and similar. These documents routinely contain personal information about third parties: the names, job titles, signatures and contact details of engineers, commissioning technicians, designers, principal contractors and duty holders. We process that information because it belongs in the deliverable, and because a handover document is not compliant without it.

When we invoice you. Billing contact, purchase order or cost code, and payment records.

We do not collect special category data, and we do not ask for it. Please do not send us health, biometric or similar information — if it appears in project material, tell us so we can remove it.

2. Why we are allowed to process it

  • Answering enquiries — our legitimate interest in responding to people who contact us about our services.
  • Delivering a project — performance of our contract with you, and our legitimate interest in producing a document that meets CDM 2015, BSRIA BG 79 and Building Safety Act requirements.
  • Third-party personal data inside project files — our legitimate interest, and yours, in compiling complete and accurate handover documentation. We have assessed that this is a limited and expected use: the individuals concerned provided the information in a professional capacity for exactly this purpose.
  • Invoicing, accounting and record-keeping — our legal obligations under UK company and tax law.

3. Who we share it with

We do not sell your information and we do not share it for marketing. We use the following providers, each of which processes data on our instructions:

  • Microsoft (Microsoft 365, SharePoint, Outlook) — email, file storage and project folders. UK / EU.
  • Automattic (WordPress.com, Jetpack) — this website and its enquiry form. USA, under approved transfer safeguards.
  • Intuit (QuickBooks) — invoicing and accounting records. UK / USA, under approved transfer safeguards.
  • Anthropic (Claude) — AI-assisted drafting, see section 4. USA, under approved transfer safeguards.

We will also disclose information where the law requires it, or to our accountant, insurer or legal advisers where necessary.

4. AI-assisted document production

We use AI tools, currently Anthropic’s Claude, to help draft and structure documents from the material you send us. You should know three things about this:

  1. A qualified person reviews everything. No document leaves us without being checked by a human against a written quality-control checklist. The AI drafts; we are responsible for the result.
  2. Your material is not used to train AI models. Anthropic’s commercial terms state that data submitted through its API is not used to train its models. We rely on that undertaking and review it periodically.
  3. We keep the exposure minimal. We pass only the material needed to produce your document, and we do not retain project content in AI systems beyond the production of that document.

If you would prefer your project to be produced without AI assistance, tell us before we start and we will confirm whether we can accommodate it and what that means for the price and timescale.

5. How long we keep it

  • Enquiries that do not become work — 12 months, then deleted.
  • Project files and deliverables — six years from completion of the project. This matches the limitation period for a negligence claim, and means we can reissue or defend a document if it is ever questioned. After six years the project folder is deleted.
  • Accounting records — six years from the end of the accounting period, as required by law.

6. How we keep it safe

Project material is held in access-controlled Microsoft 365 storage. Each client’s folder is shared only with that client and with us — we do not use public or open links. Access is protected by multi-factor authentication. Where we engage a freelance reviewer, they sign a written confidentiality agreement before they are given access to anything.

7. Your rights

Under UK GDPR you can ask us to give you a copy of the personal information we hold about you, correct it if it is wrong, delete it, restrict or object to how we use it, or provide it in a portable format. You can also object to processing we carry out on the basis of legitimate interests.

To exercise any of these, email info@sierrabuildingservices.co.uk. We will respond within one month. There is no charge.

If you are unhappy with how we have handled your information, please tell us first so we can put it right. You also have the right to complain to the Information Commissioner’s Office at ico.org.uk/make-a-complaint or on 0303 123 1113.

8. Cookies

This website is hosted on WordPress.com and sets a small number of cookies that are necessary for the site and its enquiry form to work, and to collect anonymous visitor statistics. We do not run advertising cookies or third-party tracking. If we add analytics or advertising in future we will update this policy and add a cookie banner before doing so.

9. Changes to this policy

We will update this page when our practices change and will revise the date at the top. Material changes affecting existing clients will be notified by email.