The new development of 2 residential properties at Lime Kilns, East Calder in Scotland has
been provided with a high-quality VOC protection barrier in the form of Protech VOC Flex
from the A. Proctor Group.
Prior to construction and in line with the guidance and legislation for brownfield site
developments, an investigation of the site revealed the presence of historic VOCs. In
full compliance with CIRIA C735 and the guidelines laid out in the British Standard
8485:2015 (+ A1 2019) and CIRIA C748, the geomembrane was installed by the specialist
gas membrane contractor Structureseal Services. As laid out in CIRIA C735 the VOC
geomembrane was thermal heat welded and all joints air lance tested in accordance with
ASTM D4437-08 2013 in conjunction with the third-party validation engineer. The thermal
heat welded joints were carried out by approved NVQ Level 2 gas membrane installers,
including the installation of the A Proctor Group’s Provoid 25 cuspated geocomposite
subfloor venting blanket to form a passive dispersal layer in conjunction with Provoid ground
mounted gully vents to the perimeter of the houses. This combined achieved a “very good
performance” passive venting installation fully compliant with BS8485:2015 (+A1 2019)
Table 6.
Martin Taylor, Commercial Director of Structureseal Services commented, “we have
successfully used Protech VOC Flex on several VOC vapour protection projects. It offers
high-performance protection in compliance with CIRIA C748, is extremely robust and
has many benefits which make it easy to install on site. One of these being that when the
geomembrane is folded the product has “memory”, which enhances the speed, finished
appearance and quality of the overall installation.”
The A. Proctor Group has over twenty years of experience in providing solutions for
the safe development of brownfield land, and a range of ground gas protection products
to make the development of these sites safer and easier. Following extensive research
and development, Protech VOC Flex was introduced as a high-class performance VOC
membrane, part of the Group’s comprehensive range of ground gas protection products.
Protech VOC Flex is a 6-layer flexible proprietary reinforced VOC gas barrier suitable for
use on brownfield sites that require protection from dangerous contaminants.
The A. Proctor Group’s expert design and specification advice allowed the project at East
Calder on behalf of Concept Completed, to achieve a fully compliant design for ground gas
protection measures for the project. Working with developers, specifiers and contractors
the A. Proctor Group can provide safe, cost-effective and value-engineered solutions.
Technical services include CAD detailing and project-specific recommendations utilising the
latest guidance and ensure compliance with current legislation and standards including the
BS8485:2015 (+ A1 2019) and CIRIA C748. Site Investigation Reports and Gas Monitoring
Results can be reviewed and specialist advice can be provided to ensure full compliance and
correct product selection.

Protech VOC Flex
Brochures

Datasheets

Installation Guides

Material Properties

UK Availability

Certification

CAD Details

Global Availability

Material Properties
Protech VOC Flex
Property | Test Method | Result |
---|---|---|
Roll Size | - | 50 x 2 m |
Thickness | - | 0.55 mm |
Weight | ISO 536 | 564 gsm |
Tensile Strength | EN 12311-1 | MD 700 / CD 640 N/50mm |
Elongation | EN 12311-1 | MD 30% CD 25% |
Nail Tear Resistance | EN 12311-1 | MD 500 / CD 540 N |
Methane Permeability | ISO 15105-1 | ≤0.1 ml/m2/day |
Determination of Chemical Resistance | EN 14414 Methods A-D | Pass - No visual degradation |
Resistance to Naphthalene | ISO 15105-2 (EN 14414 Method C) | Pass |
Resistance to Benzene | ISO 15105-2 (EN 14414 Method C) | Pass |
Resistance to Toluene | ISO 15105-2 (EN 14414 Method C) | Pass |
Resistance to Hexane | ISO 15105-2 (EN 14414 Method C) | Pass |
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