High-Capacity Air Tightness Testing

High-Capacity Air Tightness Testing for Buildings Over 10,000 m²

As building regulations tighten and energy performance standards continue to rise, airtightness testing has become a critical part of modern construction. For large commercial and industrial developments, achieving compliance is no longer just about meeting regulations — it’s about improving long-term efficiency, reducing operational costs, and ensuring high-quality construction standards.

However, testing very large buildings requires far more than standard equipment and basic experience.

APT Sound Testing is one of the few specialist companies in the UK with the capability to carry out air pressure testing on buildings exceeding 10,000 m². Backed by a high-powered 6-fan blower door system, Level 2 ATTMA registration, and UKAS accreditation, we provide reliable, accurate, and fully compliant airtightness testing for even the most complex projects.

Specialist Equipment for Very Large Buildings

Most air tightness testing companies operate with one or two fans, which is generally sufficient for residential properties and smaller commercial units. Large-scale developments, however, demand significantly greater airflow and testing capacity.

APT Sound Testing has invested in an advanced multi-fan blower door system specifically designed for testing large-volume buildings, including:

• Warehouses and logistics centres
• Supermarkets and large retail developments
• Schools, hospitals, and public sector buildings
• Multi-storey residential developments
• Industrial and manufacturing facilities
• Buildings with complex internal zoning

Our high-capacity system allows us to maintain stable test pressures across vast internal spaces while delivering highly accurate results. This not only ensures compliance with ATTMA TSL1, TSL2, and Part L requirements, but also reduces testing time and minimises disruption to construction programmes.

For buildings over 10,000 m², this level of capability is essential — and still relatively rare within the industry.

Why Accreditation Matters

Large-scale airtightness testing is not simply about using larger fans. It requires technical expertise, precise procedures, and recognised accreditation to ensure results are accepted by Building Control and project stakeholders.

APT Sound Testing is:

• Level 2 ATTMA Registered — authorised to test large, complex, and multi-zone buildings
• UKAS Accredited — providing independently verified testing procedures and traceable results

This gives contractors, developers, and consultants complete confidence that testing is carried out to the highest industry standards.

Our accreditation helps clients achieve:

• Compliance with Building Regulations Part L
• Acceptance by Building Control and warranty providers
• Support for BREEAM and sustainability targets
• Reduced risk of costly retesting or project delays

For large and high-value developments, using an accredited testing provider is essential to avoid unnecessary complications later in the programme.

Advanced Air Leakage Diagnostic Surveys

Achieving airtightness on large buildings can be challenging. Minor defects repeated across thousands of square metres can quickly lead to significant leakage rates.

To help identify and resolve problems efficiently, APT Sound Testing provides detailed air leakage diagnostic surveys using advanced testing methods.

Smoke Testing

Under pressurised conditions, smoke testing visually identifies leakage paths throughout the building envelope, including:

• Cladding interface failures
• Poorly sealed service penetrations
• Faulty window and door seals
• Roof-to-wall junction leakage
• Hidden construction gaps and voids

This allows contractors to pinpoint issues quickly and carry out targeted remedial works.

Thermal Imaging Surveys

Thermal imaging inspections are another highly effective diagnostic tool, especially when combined with depressurisation testing.

Thermal imaging can identify:

• Cold air infiltration
• Missing or poorly installed insulation
• Thermal bridging
• Hidden air leakage not visible during visual inspections

These surveys provide valuable insight into both airtightness performance and overall building envelope quality.

Detailed Leakage Reporting

APT Sound Testing provides comprehensive reports designed to help site teams resolve issues quickly and efficiently.

Our reports include:

• Annotated photographs and thermal images
• Leakage severity assessments
• Root-cause analysis
• Recommended remedial actions
• Prioritised sealing guidance

This structured approach helps contractors achieve compliance faster while avoiding unnecessary remedial costs.

Why Large Buildings Need Specialist Testing

Testing a building over 10,000 m² is fundamentally different from testing smaller properties. It requires:

• High-capacity blower door systems
• Advanced airflow measurement
• Multi-zone testing strategies
• Experienced engineers
• Robust diagnostic procedures
• Accredited reporting methods

Without the correct expertise and equipment, test results can become unreliable — potentially leading to failed compliance, programme delays, and expensive retesting.

APT Sound Testing removes these risks by providing a complete large-building airtightness testing solution from initial consultation through to final certification.

Supporting Projects from Design to Completion

Modern construction programmes are demanding, and airtightness performance must often be achieved within tight timescales.

APT Sound Testing supports clients throughout the entire process with services including:

• Design-stage consultancy
• Pre-test inspections
• Large-scale air pressure testing
• Diagnostic leakage surveys
• Remedial guidance and support
• Fast-turnaround reporting

Our objective is simple: help projects achieve compliance first time.

Airtightness Testing for BREEAM and Energy Efficiency

For developments targeting BREEAM certification, improved EPC ratings, or enhanced energy performance, airtightness plays a major role in overall building efficiency.

Our testing services support:

• BREEAM Hea 02 and Ene 01 credits
• Improved EPC and SBEM calculations
• Reduced heating and cooling demand
• Lower long-term operational energy costs

On large buildings, even small improvements in airtightness can result in significant energy savings over the building’s lifespan.

Why Choose APT Sound Testing?

APT Sound Testing is trusted nationwide for large-scale airtightness testing because we combine specialist equipment with accredited expertise.

Our services include:

• High-powered blower door systems for buildings above 10,000 m²
• Level 2 ATTMA Registered testing
• UKAS Accredited procedures
• Smoke testing and thermal imaging diagnostics
• Detailed and actionable reporting
• Fast turnaround times
• Nationwide coverage

We continue to support contractors, developers, architects, and consultants across the UK on some of the country’s most demanding airtightness projects.

Contact APT Sound Testing

For large-scale air pressure testing, air leakage diagnostics, or technical advice, contact APT Sound Testing today.

Phone: 07775 623464
Email: info@aptsoundtesting.co.uk
Website: https://aptsoundtesting.co.uk/