|CIRIA 665 CHARACTERISTIC SITUATION 2||CIRIA 665 CHARACTERISTIC SITUATION 3-6||BS8485 AMBER 1||BS8485 AMBER 2 & RED||BRE 211 RADON||NHBC AMBER 1||NHBC AMBER 2|
Protech GM+ is a high performance proprietary reinforced gas barrier, that has been specifically designed to conform with the latest guidance documents. Due to its unique composition the membrane is extremely robust and flexible and therefore easy to install on site. The membrane also provides protection from damp and, therefore, there is no need to install a separate DPM.
Ciria 665, BS8485 & Local Authority Ground Gas Handbook recommend that gas membranes are specified on the basis of the ‘need to survive’ construction, i.e. use one that is puncture and tear resistant.
Thickness should not be the main determinant of the suitability of a membrane for a particular site, although it can indirectly influence some key performance parameters.
In practice, because of the nature of construction sites, the durability, survivability and robustness of membranes are equally important than purely permeability to gas.
Protech GM+ incorporates a reinforced grid to ensure that maximum protection is achieved when installed to manufacturers’ instructions.
The need for high quality workmanship during installation should not be under-estimated. The health and safety of the occupants of the building is dependant on its satisfactory performance. If installed incorrectly or damaged during the construction process, the membrane is rendered ineffective and will fail to provide adequate protection against the ingress of ground gas or vapours.
|CO2 PERMEABILITY BRE GAS CHROMATOGRAPH||0.06 g/m2 31 ml/m2/day|
On sites where venting is required, our Provoid Venting System should be used. We can provide design advice for both passive and active venting systems to suit individual site requirements.
Roll out Protech GM+ gas membrane and apply Protech GM doublesided sealing tape 50mm from edge of Protech GM+ gas membrane and run a stiff brush down the Protech GM double-sided sealing tape to ensure it is well adhered to Protech GM+ gas membrane.
Roll out next sheet of Protech GM+ gas membrane maintaining a minimum 150mm overlap with bottom sheet.
Starting at one end of the run of membrane, pull back the corner of the top sheet of the Protech GM+ gas membrane to expose the Protech GM double-sided sealing tape. Pick the release paper form the top of the Protech GM double-sided sealing tape and pull the release paper away from the Protech GM double-sided tape whilst walking down the length of the Protech GM+ gas membrane to be jointed.
To complete the joint, apply firm pressure with a stiff brush to the joint as shown below to ensure that any trapped air escapes and the two sheets of Protech GM+ are firmly adhered and well sealed.
Preformed Protech Tophats are available in all popular pipe sizes ranging from 55mm-225mm
BS 8215, Design and Installation of DPCs, recommends that ‘3-dimensional shapes in DPC should be pre-fabricated’ avoiding site fabrication.
The A. Proctor Group Ltd recommends the use of preformed corner units to achieve gas tight seal.
Preformed corner units are a technically better solution for gas proofing and are also cost effective, due to the added time it takes to create similar details in situ.