Cost & commercial
A compliant clean is not a flat fee with a certificate stapled on. The figure is built from a handful of real drivers - system size, grease load, access, height and the verification behind the certificate. Here is each one.
The short answer
A TR19 Grease clean is priced from the job, and the job is the sum of a few things: how big the system is, how much grease is in it, how hard it is to reach, whether the work is at height, and the verification and certification that make the result defensible. Change any one and the price moves. Understanding the drivers is how you read a quote and tell a fair one from a hopeful one.
Size, scope and grease load
The first driver is scope. A compliant clean runs the whole system - canopy, filters, the horizontal and vertical ductwork, the fan and motor, and the discharge point - so a longer, more complex network simply takes more labour, more equipment and more hours. Bends, risers and hidden sections all add time because each has to be reached and cleaned, not just passed over.
The second is grease load. A system cleaned on schedule carries soft, manageable deposits; a first-ever or long-overdue clean carries thick, carbonised grease that has to be scraped, brushed and degreased off, with more waste to remove. Soft grease is measured with a Wet Film Thickness Test and hard carbonised deposits with a Deposit Thickness Test - and the heavier the reading, the more work the clean represents.
Access, height and timing
Access is often the biggest swing. Ductwork concealed above false ceilings, in roof voids or up external walls takes time and equipment to reach, and if the system has too few access panels, provision has to be made before it can be cleaned to bare metal. Height compounds this - vertical risers and roof-mounted fans mean working at height with the right access equipment, which adds cost and planning. And timing matters: most kitchens are cleaned overnight or early morning to protect trading, which carries an out-of-hours labour premium that is usually worth paying.
These are the drivers that make two similar-looking kitchens price differently. A short, low-level, well-maintained system barely touches them; a tall, concealed, neglected one hits every one. A survey is what reads them accurately, which is why a real quote follows a survey rather than a phone call.
The verification is part of the price, not an extra
The last driver is easy to overlook: verification and certification are work, and a compliant price includes them. That means the post-clean testing that confirms surfaces below fifty microns, the qualified technician time to carry it and sign it off, the report with before-and-after photographs and deposit readings, and the entry on the register that makes the certificate checkable. A quote that leaves these out looks cheaper because it is doing less - and a certificate without them behind it is worth little when it is examined.
Questions
System size and scope, grease load, access provision, whether the work is at height, timing such as out-of-hours, and the verification and certification. The price is the sum of these, not a flat fee.
A regularly cleaned system has soft, manageable deposits; a neglected one has thick, carbonised grease that must be scraped, brushed and degreased off with more waste to remove. Heavier readings mean more work.
Often a lot. Concealed runs above ceilings or up risers take time and equipment to reach, and if there are too few access panels, provision must be made first. Height adds working-at-height equipment and planning on top.
No - the verification and certification are part of a compliant clean. That includes post-clean testing to below fifty microns, qualified technician time, the report with photos and readings, and the register entry. A quote that omits these is doing less.
Because the drivers - size, load, access, height - can only be read by looking. A survey measures the grease and checks what is reachable, turning the drivers into a firm, itemised figure instead of a guess.
Phoenix Duct Clean · by the numbers
We survey, then quote with the drivers itemised - size, grease load, access, height and verification - so you can see exactly where the cost sits and why, rather than a single opaque figure.