Twin wall insulated exhaust system

THERM+ GEP is high quality, stainless steel, twin wall, pre-insulated exhaust system.

With a continuously welded liner and outer casing provides a pressure resistant joint for applications up to 5000 Pa positive pressure H1 level at 600°C flue gas temperature (BSEN 1856-1).

Available in 50mm or 100mm insulation, Therm+ GEP has been specially designed for standby diesel and gas fuel generators. Complete with a comprehensive range of standard accessories to suit all applications and environments.

It is available in 6 diameters (from Ø150 up to Ø400mm).







Product details

>Optimisation: High thermal performance ensures maximum efficiency of exhaust operation and minimum use of space in the building with controlled surface temperature guaranteeing personnel safety.

> Performance: CE marked to BSEN 1856-1

Safety: Very robust joints require brackets at only 3 metre intervals, with up to 16 metres on a base support with 3 metres free-standing capability.

> Installation: Easy to install push fit joints secured with quick action toggle clip Locking Band, wide range of quality engineered support components with exceptional ability to adjust to suit the building fabric.

> Innovation: Range of specially designed components to provide additional security to personnel and building fabric against explosion and protection of the exhaust system against implosion.

> Engineered: Pressure tight joints up to 5000 Pa (H1). Complete with a specially developed Joint Seal, expansion bellows no longer required.




All of the products offered by Cheminées Poujoulat have been rigorously tested in every configuration by the CERIC Laboratory to ensure they meet highest standards (Building Regulation Document J - Amendments to Approved Documents).


Technical data

> Insulation: 50mm

> Insulation: 100mm

> Max. Temperature limitation: 600°C
> CE marking: 0071-CPR-19655

Ø150 to Ø200 T600 H1 W V2 L50 050 O50
Ø250 to Ø350 T600 H1 W V2 L50 060 O50
Ø350 to Ø400 T600 H1 W V2 L50 070 O75


The unique push-fit system developed by Poujoulat avoids the thermal bridges at the connections and allows the free expansion of the inner wall.

Installation & regulation



We develop the product and apply it to your project.

We provide a full thermal and structural design, with working drawings, fully compliant to British and European Standards.

We produce Clean Air Act calculations and ADMS4 dispersion modelling.

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