Chimney Testing and the CPR

We test System chimney products to BS EN 1856-1 and metal flue liners and connecting flue pipes to  BS EN 1856-2

Any chimney sold in the United Kingdom (and any country in the European Union), must comply to the Construction Products Directive (CPR). A company or individual selling a chimney into the UK market must ensure that the product has a CE mark. A chimney includes everything except the appliance (e.g. woodburner) itself.

 Chimneys can be tested for :

  • Thermal performance
  • Resistance to thermal shock at 1100°C
  • Resistance to moisture ingress
  • Crushing and impact strength

We also carry out pre-approval or development tests on chimneys.

Investigational work and consultancy advice on other chimney types, including clay and concrete products is also provided on a commercial basis. On-site troubleshooting with problem chimneys or expert witness services are available.

Alternatively, our fully-equipped test rig can be made available for use by manufacturers' own staff to develop new products for market.

How do I obtain a CE Mark?

The point of a CE mark is to assure the consumer that a product is safe and fit for purpose. To obtain a CE mark for a chimney product, it must have:

  • a robust manufacturer’s file (to prove its construction quality, safety and fitness for purpose)
  • regular factory production control (FPC) inspections

How we can help

Assuming that there is an EN standard for my product… Most building products are covered by CE marking. The definitive list is held at We can look at the manufacturer’s declaration for your product and check that it complies with the appropriate EN standard. If it complies, we can then conduct a factory production control (FPC) examination of the production process for your product (one of the conditions of CE marking). We can conduct FPC assessments on any System 3 (and above) chimney. A CE mark can then be applied for.

What if there is no EN standard for my product?

Then the manufacturer must assemble a product file, which we can examine, along with a product sample. If we agree that the product is safe and fit for purpose we will write a letter on headed notepaper to confirm this. This letter is your evidence that your product:

  • Is not covered by an EN standard
  • Will pass the requirements of Building Control as regards product quality

 Such letters should be acceptable to any reasonable Building Control Officer.

What should the manufacturer's product file contain?

  • Detailed drawings defining the product
  • Materials of construction
  • Installation instructions
  • Hazards sheets etc (if appropriate)
  • Design calculations
  • Own and/or 3rd part laboratory test results
  • Written evidence of successful performance in the field over an extended period, under both reasonable use and foreseeable abuse
  • Written evidence that the product is not subject to significant numbers of complaints etc

What if the file is insufficient to show compliance?

If the manufacturer’s declaration does not comply with the standard, we can test your product and, subject to testing, provide you with a declaration that your product is fit for purpose. If further product development is required, then we can retest your product when this has taken place. We can then carry out an FPC inspection on the product.  Armed with a declaration and evidence of an FPC inspection, you can then apply for a CE mark. We have been testing chimneys for decades. 

Why Kiwa?

We have been testing chimneys for decades. Our experience, knowledge and fully equipped test laboratory make us the obvious choice for testing. We are known for being helpful, friendly and supportive too.