Medite Vent MDF


Medite Vent®

Medite Vent MDF is a high performance breathable external sheathing panel suitable for use in all types of timber frame structures. Combining high racking strength in excess of Category 1 requirements with excellent vapour permeability and high weather resistance, it is the perfect choice for the outer layer in ‘diffusion open’ wall and roofing applications.


Features and Benefits
● Breathable sheathing panel suited to diffusion open systems
● Very low water vapour diffusion factor to prevent condensation (Tested by Fraunhofer Institute for Building Physics)
● High performance – Category 1 racking strength (Tested by UKAS accredited laboratory)
● Zero added formaldehyde contributing to healthy environments
● CE Marked in accordance with EN 13986
● Manufactured from FSC® timber from our own forests

Properties: Medite Vent complies with EN 622-5 MDF.RWH requirements and EN 14964 for use in rigid underlays in roofing and walls. Medite Vent is FSC certified and manufactured from timber from our own FSC certified forests.

Timber Frame Sheathing Panel: Medite Vent is classified as a structural board which is suitable for use in humid conditions, Service Class 2 Conditions to Eurocode 5 (EN 1995-1-1). It is suitable for use in biological hazard classes 1 and 2 of EN 335-3.


Medite Vent panel fixing properties have been evaluated for typical fasteners used in the timber construction industry. The characteristic lateral load carrying capacities (Fv,Rk) for fasteners loaded in single shear in C16 timber are shown as below:

The lateral shear capacity of fasteners can be used for racking design to EN 1995-1-1. The results are validated with racking tests performed in accordance with EN 594:2011.


Installation: When installing Medite Vent boards a 3mm expansion gap should be left around the edges of the board to accommodate any movement resulting from changes in humidity. It is essential that the gaps are kept free from plaster, mortar and other debris during construction.

Medite Vent may be installed with typical timber fixings such as nails (smooth and threaded), staples and woodscrews. Typical specified nail diameters range from 2.7mm to 3.35mm depending on the building class and method of driving. The smaller of these diameters is preferable for 38mm thick studs to reduce the possibility of splitting. All fixings should be a minimum of 50mm in length or 2.5 times the thickness of the panel, whichever is greater.

Fixings should be galvanised, stainless steel or have similar corrosion resistant properties.

The type size and spacing of fixings should be confirmed by the timber frame panel designer.

Fixings should be spaced at maximum 150mm centres along panel perimeters and at 300mm centres on intermediate studs. Fixings must be at least 10mm from the edge of the panel.

In order to avoid buckling, fixings should commence at the top centre of the panel and continue outwards and downwards.

Medite Vent is suitable for sheathing timber frame wall panels with stud framing not less than 38mm in width and at a maximum of 600mm centres. Suitable sawing, routing and drilling tools should always be used.

During and especially after installation the boards must be protected from direct contact with water with a suitable weatherproof breathable membrane.

Hygrothermal Design: Due to its very low water vapour diffusion factor Medite Vent is principally adopted as sheathing in applications where drying of the structure is required. If a weather/breather membrane is used in combination with Medite Vent, it is recommended to use a membrane with a vapour diffusion factor equivalent or lower to that of Medite Vent.

A condensation risk analysis or advanced hygrothermal assessment of composite wall systems is recommended to ensure that the construction will not be at risk of moisture damage throughout the life of the building. Detailed recommendations for control of condensation are given in BS 5250 which now refers to EN ISO 13788 as the method of calculation (Glaser method) but more modern and advanced methods of hygrothermal simulation are recommended, as detailed in EN 15026.

Supply: 12 x 1197 x 2397mm (other dimensions on request)

Storage: Medite Vent sheets should be stored horizontally and lifted clear of the floor using dry bearers as supports. Individual bearers should be of equal thickness and placed at not more than 600mm centres.

Service: For further information relating to transportation, handling, cutting or technical advice please contact your local Coillte Panel Products Sales representative or Coillte Panel Products Technical Support Personnel through any of our European offices:
+44 (0) 1322 424900
+31 (0) 475 399740
+353 (0) 51 832700
As we continually update our technical datasheets, please check on that you have the latest version.

All Medite MDF products supplied for use in the construction and civil engineering industries are CE marked according to the requirements of the harmonized European standard for wood based panels EN 13986. This provides the necessary assurance  to customers and users that Medite conforms with the European MDF standard, EN 622-5 and meets all the essential requirements for the Construction Products Regulation (supersedes Construction Products Directive) that are relevant to the product. In accordance with the provisions of Third Party Certification required within the Final Regulations Order of the Airborne Toxic Control Measure (ATCM) by the California Air Resources Board (CARB) all Medite MDF products are CARB Phase 2 Compliant. The approved Third Part Certifier (TPC) Entwicklungs-und Pruflabor Holztechnologie Gmbh (EPHTPC No W-08-010) is contracted to Medite to perform  the quarterly assessment of the factory production control and to have stipulated formaldehyde tests carried out by the accredited EPH test laboratory.

This leaflet is provided for information purposes only and no liability or responsibility of any kind is accepted by Coillte Panel Products or their representatives, although Coillte Panel Products has used reasonable efforts to verify the accuracy of any advice, recommendation or information. Coillte Panel Products reserves the right to alteration of its products, product information and product range without any notice.


All information on this page is provided in good faith. We however cannot guarantee any of the contents.
We are always here to help in anyway we can, but you must satisfy yourself the information is correct before starting any projects,
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