Phi Group has been involved with this project, at the former Dumfries College site, for a long time prior to actual commencement on site. After a lengthy design and planning process, permission to start construction of the much needed housing was given in 2019. In all 75 units will be constructed on this part of the site for Loreburn Housing Group.

Permacrib timber crib

The project

Once planning was granted, works started quickly, with the enabling works package was let to Ashleigh (Scotland) limited. As part of the planning conditions, an acoustic bund was required on the perimeter of the site to screen the new houses from existing properties. This bund needed to be 5.0m high and 315m long, with an additional acoustic fence on top and fell within the enabling works.

The challenge

If space is not a concern, then installing a bund with gently sloping sides is possible, and is also the most cost effective solution as it is simply an earthworks exercise. However, as is often the case, space is at a premium and the land take for the bund had to be kept to an manageable level, to maximise the available development space. To do this the slopes of the bund need to be made steeper.This can be done by using back to back structures if you need to steepen up both sides, or simply steepening up one side of the slope. Reinforced soil can be a good option for this, as can a gravity retaining wall to one side of the bund.

The solution

In this instance our BBA Certified Permacrib timber crib solution was chosen as the preferred method. Phi Group designed, supplied and installed a Permacrib wall to one side of the new bund. The Permacrib retaining wall is 315m long and up to 5.26m retained height. In all over 1,500m2 of Permacrib has been installed, working closely with Ashleigh (Scotland) to ensure the bund was constructed safely and on programme.

Project facts


Loreburn Housing Group

Keller business unit(s)

Phi Group

Main contractor(s)

Ashleigh (Scotland) Limited


Asher Associates Limited