Building Performance

How your building
really performs.

We test, measure, and diagnose how buildings actually perform — not how they were designed to. Using calibrated airtightness testing, thermal imaging, and in-situ measurement, we give you the hard data you need to make informed decisions.

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The Performance Gap

Up to 5×
Gap between designed and actual energy use
£30bn
Annual cost of the performance gap to the UK
80%
Of 2050's buildings already exist today

Our Services

Six ways to measure your building.

Airtightness Testing

We conduct air permeability tests to BS EN ISO 9972 using calibrated blower door equipment. Whether you need compliance testing for Building Regulations, pre-retrofit baseline data, or quality assurance checks during construction, we deliver accurate, certified results.

BS EN ISO 9972
Deliverables: Air permeability test certificate, identified leakage paths, recommendations for improvement

Drone Thermographic Surveys

Large-scale thermal imaging from our CAA-licensed drone platform. We survey entire building elevations, roofs, and estates quickly and efficiently, identifying thermal anomalies, insulation defects, moisture ingress, and heat loss patterns.

CAA Licensed
Deliverables: Calibrated thermal images, annotated report with defect identification, RGB comparison imagery

Handheld Thermographic Surveys

Detailed, close-range thermal imaging for internal and external building inspections. We identify thermal bridges, insulation gaps, air leakage paths, moisture issues, and underfloor heating faults with precision.

Calibrated Equipment
Deliverables: Thermal survey report, calibrated thermal images with annotations, defect schedule

In-Situ U-Value Measurement

Direct measurement of how much heat passes through your building fabric under real conditions. Unlike calculated U-values, in-situ measurement tells you what your walls, roofs, and floors are actually doing — essential for retrofit planning.

BS ISO 9869-1
Deliverables: Measured U-value report, comparison with design values, recommendations for improvement

Thermal Bridge Assessment

Identification and quantification of thermal bridges — the junctions and details where heat bypasses your insulation. Critical for retrofit design, Passivhaus projects, and understanding real heat loss.

Psi-value calculations
Deliverables: Thermal bridge analysis report, psi-value calculations, design recommendations

PHPP Energy Modelling Support

We provide measured input data for Passivhaus Planning Package (PHPP) models — real airtightness results, measured U-values, and thermal bridge values that make your energy model reflect reality, not assumptions.

PHPP compatible
Deliverables: PHPP-ready data inputs, supporting test certificates, consultation on building performance

Why Measure

The gap between design and reality.

Buildings rarely perform as designed. Research consistently shows a significant "performance gap" between predicted and actual energy use. Our testing bridges that gap — giving you the evidence to make better decisions, prove compliance, secure funding, and deliver buildings that actually work.

Whether you're planning a retrofit, verifying new construction, or building an evidence base for funding applications — measured data beats assumptions every time.

Retrotec blower door equipment set up for airtightness testing in a doorway

Standards & Accreditations

BS EN ISO 9972
BS ISO 9869-1
Building Regs Part L
MCIAT Chartered
CAA Licensed
Calibrated Equipment

FAQ

Frequently asked questions

What is an airtightness test and do I need one? +
An airtightness test (air permeability test) measures how much air leaks through your building's envelope. Under current Building Regulations, all new dwellings in the UK require an airtightness test. It's also increasingly used for retrofit assessment, Passivhaus certification, and quality assurance during construction.
What standard do you test to? +
We test to BS EN ISO 9972, which is the standard referenced by UK Building Regulations. We can also test to Passivhaus requirements where needed. All our equipment is calibrated and our results are accepted by building control throughout the UK.
How much does an airtightness test cost? +
For a standard single dwelling, airtightness testing typically costs between £250-400 depending on location and size. Larger buildings, multi-unit developments, and commercial properties are quoted individually. We provide results on site and certificates within 48 hours. Contact us for a quote.
When is the best time to do a thermal survey? +
Thermal surveys are most effective during the heating season (October to March) when there's a significant temperature difference between inside and outside the building. For drone thermography, early morning surveys before sunrise often give the clearest results.
What's the difference between drone and handheld thermography? +
Drone thermography covers large areas quickly — entire building elevations, roofs, and estates in a fraction of the time it would take from ground level. It's ideal for housing stock surveys and hard-to-reach areas. Handheld thermography provides more detailed, close-range analysis for internal surveys, specific defect investigation, and diagnostic work.

Need to know how your building really performs?

From a single airtightness test to a full estate-wide thermal survey — we'll scope the right approach for your project.

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