Building Regulations

Are a set of standards intended to protect people’s safety, health and welfare in and around built environments.

For an annexe, luxury retreat, education room or outbuilding, building controls primary focus will be the ground, structure, thermal performance, ventilation, passive and active fire measures. All of these can be easily mitigated and planned for.

Below is Schedule 2, Class 6 from the Building Regulations 2010 – this sets out exempt buildings or works.

Small Detached Buildings

1.  A detached single storey building, having a floor area which does not exceed 30m², which contains no sleeping accommodation and is a building—

(a) no point of which is less than one metre from the boundary of its curtilage; or

(b)which is constructed substantially of non-combustible material.

2.  A detached building designed and intended to shelter people from the effects of nuclear, chemical or conventional weapons, and not used for any other purpose, if—

(a)its floor area does not exceed 30m²; and

(b)the excavation for the building is no closer to any exposed part of another building or structure than a distance equal to the depth of the excavation plus one metre.

3.  A detached building, having a floor area which does not exceed 15m², which contains no sleeping accommodation.

ANX Plan Appraisal

We will assess the annexe, outbuilding or luxury retreats design and specification, for compliance with building control. Pragmatic feedback will be given on any potential contraventions to ensure your project is delivered without delays, and costs are kept under control.

Building Control Drawings

At ANX, we offer a comprehensive service for building control drawings, ensuring compliance with all regulations. Our RIBA-accredited architect will produce a full set of building control drawings tailored to your annexe, outbuilding, or luxury retreat. We review these drawings carefully and provide expert guidance on any contraventions, ensuring your project meets all required standards and regulations.

Pre Compliance

With the building control drawings, we can arrange for a building control inspector to review the documents to confirm that they are neither defective nor do they indicate that work carried out in accordance with them would contravene any provisions of the building regulations.

Notification

At ANX, we offer a service to prepare and submit a comprehensive pack of information required by local authorities or approved inspectors. This pack requires a site plan for the annexe or retreat, technical drawings, and completed forms detailing the project type, address, and specific information. Recognising that inspectors are often very busy, we prioritise building strong working relationships by submitting clear, detailed, and accurate information in a timely manner.

Inspections

Missing an inspection can be very costly and create delays. We coordinate with the inspectors, who act on behalf of the owner of the annexe, outbuilding, or luxury retreat. Typically, three key inspections are required—ground, structure, and finished build. It is the responsibility of the project team to arrange these inspections. By treating inspectors as part of the team and planning ahead, we help ensure that your project is delivered on time.

Approval

Electrical certificates for Part P of the regulations, and any other paper work will be coordinated and provided to the building control inspector. All our teams have the relevant accreditations to complete the required paper work and commissioning of services. Final approval is very rewarding as its confirmation that the annexe, outbuilding or luxury retreat meets regulations and gives closure to the project.

Why is a Build Over Agreement Required?

Building over a public sewer without approval can lead to a violation of local water authority regulations and Building Regulations.

These rules apply to annexes, garden rooms, studios, extensions, mobile home gyms, garden offices, saunas, hot tubs – in summary, anything than can obstruct access to or damage a public sewer.

Maintenance

If the sewerage company needs to carry out maintenance or repairs and the annexe, studio, mobile home or outbuilding restricts access, they could demand that you remove part or all of your annexe or outbuilding. The cost of removal and subsequent repairs would likely fall on the property owner.

Legal

The lack of a build over agreement could be flagged during conveyancing checks. This might delay a sale or lower a property’s value, as buyers may be concerned about potential risks or future liabilities

Damage

Without proper assessment and planning, the outbuilding could damage the sewer. This might occur if the outbuilding’s foundations put undue pressure on the sewer or if excavation disturbs it. A damaged sewer could lead to flooding or sewage backups, creating health hazards and further financial liabilities.

Insurance

Many home insurance providers require that any work involving public sewers be properly permitted. Without a Build Over Agreement, insurers may refuse to cover related claims, especially if the building has caused damage to the sewer.

Our Approach

ANX are able to, and have extensive experience of, obtaining build over agreements. There are three classes of build over agreement, the bigger the diameter the more rigorous the rules are.

Class 1 – Sewers up to 160mm (6″)

Class 2 – Sewers 160mm (6″) to 375mm (15″)

Class 3  – Sewers over 375mm (15″)

The following steps are required 1. Locate and determine the sewer type 2.Identify or design a solution 3. Complete the paper work 4. Submit the application 5. Complete a CCTV survey 6. Undertake construction work 6. Post construction CCTV survey 7. Receive the Build Over Agreement.

Build Over Agreement

ANX organises and provides all services required to meet the local water authority’s requirements. Each site must be assessed individually.

Identify & Review

Is a build over required? We identify the relevant water authority early in the process, as each has its own rules regarding build overs, with some authorities not accepting them. It’s important to consider the size, depth, type, and operation of the pipe, as well as to review the location, building design, and foundation arrangements.

CCTV Surveys

Asset plans supplied by the water authority are often inaccurate or unavailable. We can arrange for a survey of the drains, which may be required by the water authority both prior to and after construction in some cases.

Design & Implementation

If the a build over is required we recommend a solution, organise and submit the required information, brief yours or our site teams, monitor the site work if needed and close out any post construction requirements.

BSI

The are many certification schemes such as BSI and BREEAM. We can advise on compliance with or when certification can be used. Examples would be BREEAM for Radon or BSI3632:2023 for a mobile home. BSI3632 is a standard for the construction of a mobile home, and required to meet the zero or reduced VAT treatment.

Health & Safety

ANX is an SSIP registered member having completed the PQS Pre – Qualification – Scheme. No matter the size of the project, health & safety measures are required. At ANX we can support with construction phase plans, risk assessments, method statements, site setup requirements, inductions along with general advice.

Its not likely the project will be notifiable with HSE. A construction project is considered notifiable if it meets any of the following criteria, the project is expected to last more than 30 working days, is expected to have more than 20 workers working at the same time at any point, is expected to exceed 500 person days of construction work.

Building Safety Act 2022

We can act on your behalf and provide advice to ensure that safety is demonstrated throughout the process. While small projects may be perceived as low risk, it’s important not to underestimate the requirements, especially for commercial buildings or in situations where tight access could impact fire safety.

Central to the act is the legal requirement for all individuals and organisations involved in design and construction to demonstrate competence in ensuring compliance with Building Regulations. This obligation applies across all sectors, from small residential modifications to large-scale, complex mixed-use developments. Regardless of whether the designer or contractor holds legal responsibility for compliance, the duty to meet these standards applies uniformly to all parties involved in the process.