Phi Group Permacrib wall


Permacrib is world renown patented and BBA certified timber crib retaining wall system. It has been used extensively and successfully in Ireland for over 25 years.

Permacrib is a structurally engineered timber crib walling retaining wall system, utilising the traditional gravity wall design concept. Gravity retaining walls can designed to either BS 8002 or the latest Eurocode 7. It consists of open cell modules created by interlocking lightweight and durable timber crib walling components. When filled with compacted well graded stone, these modules have the mass required to counteract the earth pressures and surcharge loadings. Structural integrity is achieved through the interaction of the crib elements and the granular fill within.

Permacrib timber crib is also often used as a facing for other slope stabilisation systems such as reinforced earth or soil nailed embankments.


All Permacrib timber crib components are pressure treated to BS8417:2003 using High Concentration Copper Azole preservative. Complete cell penetration is achieved to give full protection. The resultant timber is fully resistant against fungal and insect attack.

This patented timber treatment process along with stringent timber selection results in a highly durable and extremely long lasting system which is highly resistant against degradation by fungi and insect attack and provides a long structural design life. The recent switch to Tanalith “E” preservative means that Permacrib timber crib is safe to use even in playgrounds.

Typical Applications

Permacrib timber crib has been used extensively and successfully in Ireland over 25 years. Past high profile applications include structures on the M11 in Kilmcanogue, Woodies in Bray, The Pavillion Shopping Centre in Swords, M3 Motorway and Limerick County Council Offices.

Typical uses include simple landscaping walls all the way up to major civil engineering retaining structures. BBA certification verifies suitability for use. Additionally, Permacrib timber crib walling can be used to provide landscaped and aesthetically pleasing face to reinforced earth or soil nailed structures. It can also act as a facing to sheet pilling or concrete retaining walls, as well as creating vertical acoustic barriers.

  • Roads and railway embankments
  • Bridge wingwalls
  • Retaining walls
  • Landscaping walls
  • Noise barrier
  • Facing for soil nailing and reinforced earth
  • Facing for sheet piling
  • Facing for concrete retaining walls

Appearance and Landscaping

Permacrib walls can also be landscaped by incorporating growbags and planting with a variety of plants and vegetation, which enhances its natural appearance, helping the wall blend into its surroundings.


Permacrib is manufactured from specially selected and graded Radiata Pine softwood timber from managed, cultivated, renewable forest resources. This ensures that environmental concerns for the conservation of resources and a sustainable future are met.


  • Semi-soft natural appearance
  • Can be vegetated
  • Great flexibility of design
  • Diverse applications
  • BBA certification
  • Simple and quick to build
  • Immediate serviceability
  • Pressure treated to BS8417:2003
  • Sourced from managed sustainable forests
  • Long Design life
  • Permacrib is now available with Tanalith “E” preservative

Permacrib has BBA approval Certificate Number 95/3115


Download Permacrib Brochure (PDF)

Download BBA Certificate Number 95/3115 (PDF)