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Family-run · South East London · Since 2019

Ventilation that actually shifts the damp

Ductwork, MVHR, extract systems and air conditioning — designed, installed and commissioned across Beckenham, Bromley, West Wickham, Chislehurst, Dulwich and South East London.

  • 20+ yearson the tools
  • CPD certificatedBESA Academy & CIBSE-approved
  • Commissionedairflow measured, not assumed

What We Do

Domestic and commercial ventilation, heating and cooling — designed properly, installed neatly, and commissioned so the airflow is measured rather than assumed.

MVHR Installation

Whole-house mechanical ventilation with heat recovery — designed, ducted and balanced so every room gets its share without throwing your heating out of the window.

  • Whole-house MVHR design and installation
  • Semi-rigid radial and rigid duct systems
  • Commissioning with measured airflow at every valve
  • Filter changes and servicing afterwards

Ductwork Installation

Rigid and spiral ductwork, sized and routed to keep resistance and noise down. Set out square and bracketed properly — because on an exposed run the setting-out is the finish.

  • Round spiral ductwork
  • Square and rectangular ductwork
  • Plastic ductwork and flat channel
  • Small-bore and semi-rigid tubing
  • Fabric duct socks
  • Insulated and acoustically lined runs

AHU & Fan Coil Units

Air handling units and fan coil units set, connected and commissioned — plinths, anti-vibration mounts, flexible connections and access left where the next person can actually reach it.

  • Air handling unit (AHU) installation
  • Fan coil unit (FCU) installation
  • In-line and mixed-flow fan installation
  • Attenuators, dampers and access panels

Extract Systems

Bathroom, kitchen and utility extract that meets the Part F rate at the grille, not just on the box. Ducted to outside properly, never into a loft void.

  • Continuous mechanical extract (MEV)
  • Intermittent extract fans
  • Positive input ventilation (PIV)
  • Commercial and kitchen extract

Air Conditioning

Installation and planned maintenance for split and multi-split systems — filters, coils, condensate and performance checked before the hot weather finds the fault for you.

  • Air conditioning installation
  • Servicing and planned maintenance
  • Filter, coil and condensate cleaning
  • Fault-finding and performance checks

Maintenance Plans

A system nobody services stops doing what it was installed to do, quietly. Pick the interval that suits the kit and we book it in rather than waiting for you to notice.

  • Three-monthly service visits
  • Six-monthly service visits
  • Annual service visits
  • Reactive call-outs for existing customers

Damp & Mould Surveys

Measurement first: humidity, surface temperatures and actual extract rates. You get a written report on what is causing it, not a guess and a quote for a bigger fan.

  • Humidity and surface temperature readings
  • Measured extract rates at every terminal
  • Written report with the cause named
  • Landlord and managing-agent reports

Commercial Fit-Out

Supply and extract for units, venues and workspaces — coordinated with the other trades so the ductwork lands where the ceiling design says it should.

  • Warehouse and industrial unit ventilation
  • Gyms, venues and hospitality
  • Offices and workspace fit-out
  • Food production and clean spaces

Landlord Damp & Mould — Awaab’s Law

Investigation, a written report naming the cause, the fix, and a dated evidence trail — because the question is no longer whether you fixed it, but whether you can show what you did and when.

  • Damp and mould investigation with recorded readings
  • Written report against the Approved Document F minimums
  • Extract, MEV, PIV or MVHR remediation
  • Commissioning certificate with the measured rate at each valve
  • Every document dated and downloadable from the client portal
How this works for a portfolio

Heat recovery, in section

Where the warmth goes

An extract fan throws your heating out through the wall. A heat recovery unit takes the warmth out of the stale air on its way past and hands it to the fresh air coming in. Scroll to follow one lungful of air all the way through the machine.

OUTSIDE INSIDE — CEILING VOID BEDROOM BATHROOM Condensate drain, trapped HEAT RECOVERY UNIT 21°C from kitchen & bathroom 6°C leaves cold 3°C outdoor air 18°C delivered to the bedrooms WHAT IS INSIDE 1 Filter on each incoming stream 2 Counter-flow heat exchanger 3 One fan each way, balanced 4 Insulated — outdoor runs only 1 2 3 4 Heat crosses. The air does not.
  • Insulated — outdoor runs only
  • Filter on each incoming stream
  • Counter-flow exchanger

Illustrative figures at 85% heat recovery on a 3 °C day. The real numbers depend on the unit and the duct layout, and are proved by measurement at commissioning — not by the brochure.

  1. 1

    Extract · 21 °C

    The damp air leaves first

    A valve in the bathroom ceiling pulls air out continuously — from the rooms where the moisture is actually made. It leaves at room temperature, taking the moisture with it before it reaches a cold wall and turns into condensation.

  2. 2

    Exhaust · 6 °C

    It gives up its warmth on the way out

    Through a filter, through one half of the exchanger, through the fan and out to the wall grille. By the time it reaches the outside it is close to outdoor temperature — the warmth you paid for has been left behind in the unit.

  3. 3

    Intake · 3 °C

    Cold fresh air comes in the other side

    Filtered outdoor air enters through its own grille, set well away from the exhaust so the unit can't breathe back in what it has just thrown out, and runs into the other half of the exchanger. The plates keep the two streams apart: heat passes between them, air never does.

  4. 4

    Supply · 18 °C

    It arrives warm, where you sleep and sit

    The warmed fresh air is delivered to the bedrooms and living room. That is the whole trick: the full air change the regulations ask for, without paying to heat the house twice — which is exactly what an extract fan on its own makes you do.

About us

You deal with the person who surveyed it

Cavalli Ventilation is a family-run business in South East London. Niki has worked in ventilation since 2003 and has traded as Cavalli Ventilation since July 2019. His father works alongside him, and his son joins them when they are busy. The person who comes out and looks at your property is the person who does the work.

We are ventilation engineers first. We design, install and commission MVHR, MEV, PIV, extract systems, air handling units, ductwork, duct socks and air conditioning, across both commercial and residential work. That is the reason our damp surveys measure the ventilation rather than just recommending you improve it — it is the system we install for a living, and we can prove what it achieves before and after.

We do not do bodge jobs. Every install is left as though it were going in our own home — set out properly, finished properly, commissioned to a measured rate and documented. If it does not look right, it is not finished.
  • 2003 In ventilation since
  • July 2019 Trading as Cavalli Ventilation
  • Family-run Three generations on the tools
  • Measured Airflow recorded at every terminal, not assumed
  • Commercial & domestic Warehouses and gyms through to a single bathroom fan
  • Company no. 12092552 Registered in England & Wales

Recent work

Bare soffit to a commissioned system

Drag the handle across the photograph. This one is LT Foods in Harlow: air handling units, insulated supply ducting run the length of the space, and grilles set out to give even distribution across the floor — then balanced and measured before we called it finished.

Photographs of recent installations are on our Instagram while we put this gallery together.

See our work on Instagram
Heating & cooling ductwork

Family-run since 2019, and still the people who turn up

You deal with the same engineers from survey to commissioning. No call centre, no subcontracted crew you have never met, and no job signed off without the airflow measured. And you follow the whole job in our own client app — quotes, documents, servicing dates and a direct line to your engineer.

20+ Years on the tools
36 South East London areas covered
CPD certificated
  • Ventilation: Approved Document FNuaire, through the BESA Academy
  • Understanding Mechanical VentilationCIBSE-approved CPD · Airflow, through the BESA Academy

Both completed by Niki Cavalli in August 2026 — the certificates are on the site.

Commissioned, not guessed

Every install is signed off with a calibrated anemometer at the grille. A fan rated at 30 l/s routinely delivers far less once ducting, bends and a terminal are on it — the only number that counts is the one measured in your room.

Two things you can try right now

Both are free, take a minute, and tell you something useful before you speak to anyone.

Not sure where to start?

Send us a message with what you have noticed at home. We will tell you honestly whether you need a survey, a system, or neither.

Trained on the systems we install

Certificated — and here they are

Most trade sites show you a row of logos. These are the actual certificates, both sat in August 2026. Tap either one to read it, or download the PDF.

  • Company no. 12092552 Registered in England & Wales. Trading as Cavalli Ventilation since July 2019, and in ventilation since 2003.
  • Airflow measured on every install A calibrated anemometer at the grille, recorded and handed over. The only figure that counts is the one measured in your room.