Chimneys and Flues - Section 13 - Functional Requirements and Design

Oct 23, 2026

Upload by Damian

TECHNICAL MANUAL section 13 covers chimneys and flues, defining functional requirements, limitations, and key expectations for masonry, gas flue outlets, and false chimney stacks. It sets workmanship controls including commissioning certification, tolerance compliance, and technically competent installation, plus storage and testing standards for materials. It specifies design duties for efficient fuel operation, adequate combustion air, structural integrity, fire protection, weather resistance, damp proofing, and safe discharge of combustion products, including requirements for structural calculations outside Building Regulations.

LanguageEnglish

CategoryTechnology

FormatPDF

Pages15

Reading Time38 min

AccessFree to download

Functional Requirements

Masonry

Gas Flue Outlets

False Chimney Stacks

Limitations of Functional Requirements

Workmanship

Materials

Design

Masonry: General requirements

Provision of information

Construction

TECHNICAL MANUAL VERSION 11 13: CHIMNEYS AND FLUES 13. Chimneys and Flues Contents Functional Requirements 13.1 Masonry 13.2 Gas Flue Outlets 13.3 False Chimney Stacks Limitations of Functional Requirements 1. These Functional Requirements do not and will not apply to create any policy liability for any remedial works carried out by the contractor or otherwise, nor to any materials used in those remedial works. 2. The guidance provided in this Section, is guidance that provides a suggested solution to meeting the Functional Requirements. If an alternative solution is selected, then this must still meet the Functional Requirements. Workmanship 1. A commissioning certification is required for any work completed by an approved installer. 2. All workmanship must be within the tolerance requirements set out in this Technical Manual. 3. All work is to be carried out by a technically competent person in a workmanlike manner. Materials 1. All materials should be stored, installed and protected correctly in a manner that will not cause damage or deterioration of the product. 2. All materials, products and building systems shall be appropriately tested and approved for their intended purpose. 3. All load bearing structural elements providing support to the Home will have a service life of not less than 60 years, unless specifically agreed otherwise with us. All other parts of the Home will have a lesser durability and need planned maintenance, repair or replacement during that reduced period. 4. Whilst there is and can be no Policy responsibility and/or liability for any roof covering, window / door or‘Decorative external cladding’(i.e. Cladding which is decorative only and the substrate wall provides the main weather proof barrier) to achieve a performance service life of 60 years or less, such elements shall be designed and constructed so they have an intended service life of not less than where stipulated within this Manual. 5. All materials should be suitable for the relative exposure of the building in accordance with the relevant British Standards. Design 1. Chimneys, flues, flue-pipes, fireplace recesses and hearths shall be designed and constructed so that they: a. Ensure efficient operation of the fuel-burning appliance for which they have been designed; b. Are provided with sufficient air for proper combustion of the fuel; c. Are structurally sound and do not adversely affect the structural stability of the building where they pass through floors, walls or roofs; d. Protect the structure and fabric of the building from the effects of fire; e. Do not adversely affect the ability of the building to resist the effects of weather and ground moisture; f. Discharge the products of combustion safely to the outside air. 2. Structural elements outside the parameters of Building Regulations must be supported by structural calculations provided by a suitably qualified expert. 3. Damp proofing works should prevent any external moisture passing into the internal environment of the building. © MD Insurance Services Limited 2023 388 CHIMNEYS AND FLUES 13. Chimneys and Flues 13.1 Masonry 13.1.1 MASONRY: General requirements Provision of information A full set of design drawings and specifications shall be made available to the Warranty Provider and all other interested parties prior to the associated works starting on site. This may include: 1. Design details indicating proposed chimney position, layout and height. 2. Details and specification of all materials to be used in the construction of a chimney (e.g. DPC, flashing, soakers, proposed flues, etc.) 3. Details of fire stopping in cavities around flue penetrations. 4. Details of fire places and hearths. 5. A copy of a commissioning certificate will be required at completion to be handed to the Warranty Surveyor. The Warranty surveyor, at their discretion, may also request supporting information tha

FAQs

What information must be provided before chimney works start on site?

A full set of design drawings and specifications must be made available to the Warranty Provider and other interested parties before work begins. This includes chimney position, layout and height, materials specifications, fire stopping details, and information such as commissioning certification at completion.

What requirements apply to workmanship for completed chimney and flue works?

Commissioning certification is required for work completed by an approved installer. All workmanship must meet the tolerance requirements in the Technical Manual and be carried out by a technically competent person in a workmanlike manner.

How should chimneys be designed and constructed to meet the manual’s performance goals?

Chimneys and related components must ensure efficient appliance operation, provide sufficient air for proper combustion, protect the building structure from fire effects, maintain resistance to weather and ground moisture, and safely discharge combustion products to outside air.

Oct 23, 2026

Upload by Damian