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EAC South West Energy Assessment Consultancy

Building Regulations · Part L

Air Tightness Testing in Cornwall & the South West

EAC South West provides CIBSE TM23 Level 1 air tightness testing in Cornwall and across the South West using UKAS-calibrated Pulse equipment for buildings up to 4000 m³. Fast, accurate and minimally disruptive—results accepted by Building Control.

What is air tightness testing?

Air tightness testing (often called an air pressure test) measures uncontrolled air leakage through the building envelope. High leakage means higher heat loss and higher energy bills.

Building Regulations. New builds, conversions, and many renovations require testing to demonstrate compliance with Part L.

Why our Pulse method?

  • Minimal disruption — low-pressure pulse avoids extensive door sealing and stress on the fabric.
  • Faster turnaround — quick setup and analysis for faster completion.
  • Accurate permeability — robust results accepted by Building Control.

Timing

When should testing be carried out?

Stage 1

Envelope completion (pre-finishes)

Catch issues early to avoid delays and rework.

  • Identify air leakage paths before finishes
  • Discuss observations on site with PM
  • Agree remedials without holding up programme
Stage 2

Final test (pre-handover)

Confirm compliance and issue the report.

  • Windows/doors fitted and sealed
  • Electrical outlets fitted
  • Ventilation and services commissioned

Related services: SAP / EPC · Mechanical Ventilation Testing · Building Regulation Compliance.

Pre-test checklist

What we need before testing

Documents to send us

Email ahead of your appointment.

  • Floor plans and section drawings
  • Design-stage SAP report for each dwelling
  • Site address and main site contact

Email documents

On-site ready checks

Have these complete before we arrive.

  • Services sealed: pipe/cable penetrations
  • Vapour barrier: taped and sealed
  • Trickle vents: installed & closed
  • Loft hatch: in place with draught strip
  • Water traps: filled
  • Windows/doors: perimeter sealed, draught seals fitted
  • Boiler flue: sealed around penetration
  • Power on site

On-site testing

What to expect on the day

We bring our portable Pulse system to site and complete low-pressure tests with minimal disruption. Results and observations are discussed with your project manager, and a formal report can be produced.

Arrival & setup

Quick pre-check, confirm power, and identify any obvious leakage points for sealing.

Pulse test

Low-pressure air pulse measurement — fast, accurate, and gentle on the building envelope.

Results & advice

We review findings on site and advise practical next steps to meet Part L requirements.

Common areas of leakage

Standards & schemes

EAC South West accreditations

Independently accredited testing with calibrated equipment — evidence Building Control can rely on.

Book your air tightness test

Fast, accredited testing for compliant handovers — typically with minimal disruption on site.

We cover Cornwall (Penzance, Truro, Falmouth, St Ives), plus Devon, Somerset & Dorset.

Email us to schedule
or call 07866153540

Air tightness testing – FAQs

Do you offer air tightness testing in Cornwall?

Yes. We test across Cornwall—Penzance, St Ives, Truro, Falmouth and beyond—and the wider South West. We’re CIBSE TM23 Level 1 accredited and use UKAS-calibrated Pulse equipment.

Is Pulse testing accepted by Building Control?

Yes. Our results are accepted by Building Control Bodies. You receive an official report that demonstrates compliance with Part L.

When’s the best time to book?

Ideally twice: once at envelope completion (pre-finishes) to catch leaks early, and again pre-handover for the final certificate.

Do you cover the South West outside Cornwall?

We regularly test in Devon, Somerset and Dorset. Contact us to check availability.