Chimneys

Chimneys serve to discharge flue gases into the outside air via an outlet above roof level. They must be designed in such a way that no flue gases can escape into living areas and the surrounding building components are not exposed to excessive temperatures. In cases where resistance-to-fire requirements exist in accordance with the Building Codes of the federal states (Landesbauordnungen), it must also be ensured that the fire cannot spread to other storeys.

Chimneys are divided into Chimneys for solid fuels and Chimneys for liquid and gaseous fuels.

Chimneys for liquid and gaseous fuels serve to discharge flue gases from the combustion of heating oil or gas.

Chimneys for solid fuels serve to discharge gases from the combustion of solid fuels, such as pellets or briquettes. During the combustion, soot may accumulate on the insides of the building components carrying the flue gas and may lead to soot fires with temperatures exceeding 1,000 °C. For this reason, chimneys for solid fuels must be designed to be resistant to soot fire.

Condensate can form during the combustion of solid, liquid or gaseous fuels. Chimneys designed for operation under these wet conditions must therefore be condensate-resistant and feature condensate drainage.

Regulatory framework

See Fittings, components and thermal insulation products for chimneys and Chimneys for liquid and gaseous fuels.

Application forms

National procedure

A national technical approval (abZ) and/or oder general construction technique permit (aBG) is granted upon application (see Model Building Code (MBO), Sections 16a(2) and18(2) and (4)). This also applies to amendments and supplements to, or renewals of existing approvals and/or construction technique permits.

No formal requirements apply. The following information is needed: name and address of the applicant, description of the product and/or construction technique and its field of use or application, type of decision required (new decision, amendment or supplement to, or renewal of, an existing decision).

Please feel free to use the template below.

Application for a national technical approval and/or construction technique permit (3 pages)

Version: January 2018; Application form

Application for amendment / supplementation / renewal of a national technical approval and/or construction technique permit (4 pages)

Version: January 2018; Application form

Guideline: How to provide drawings for national technical approvals and general construction technique permits (5 pages)

Version: July 2017

European Technical Assessment (ETA)

To start the ETA procedure, please submit the form below. We will then check if the prerequisites for issuing an ETA are met, i.e., in particular, if the product is not fully covered by an existing harmonised standard. If the prerequisites are met, we will check whether a European Assessment Document (EAD) covering the requested assessment scope already exists or still needs to be developed. If an EAD needs to be developed or amended, a complete technical file needs to be established before the procedure can begin.

Form for requesting a European Technical Assessment (ETA) (2 pages)

Last updated: 16 June 2022

Voluntary evaluations of fitness for use

Where the relevant harmonised standard is incomplete, economic actors can provide product performance information on a voluntary basis. DIBt offers independent validation and confirmation of such additional performance information in the form of a voluntary evaluation of fitness for use.

Order for an evaluation (4 pages)

of fitness for use of construction products

Ronny Schmidt
Head of Section – Combustion Appliances, Chimneys, Building Services

Phone +49 30 78730-473
Email rsi(at)dibt(.)de

Legal reference documents

Testing, certification, inspection