Case Studies

Demolition and Site Clearance Work at Ockford Ridge

LOCATION Ockford Ridge
Godalming
Surrey GU7 2NR
CONTRACT START DATE October 2016
CONTRACT COMPLETION DATE TBC

Demolition and Site Clearance Work at Site B, 21 – 34 (odds & evens) Ockford Ridge, Godalming, Surrey GU7 2NR

Waverley Borough Council is investing in its housing stock at Ockford Ridge, Godalming to enhance it for the benefit of its existing residents and future generations. Ockford Ridge housing is 80 years old and was originally built to house the workers who constructed the A3. Six sites (A to F) are being redeveloped in phases up until 2025.

Dorton Demolition & Excavation Limited (Dde) completed demolition works to Site D in October 2016.  Site D, two-storey semi-detached houses Nos. 45, 46, 47, 48, 49, 50, 51 & 52 Ockford Ridge, was the first to have been completed and is now fully occupied with six houses and ten flats. Ground works were completed in 2017 with no obstructions encountered in the ground.

Site D – October 2016

Site D – July 2018

Dde was awarded sites B and C demolition contracts through competitive tendering under a public procurement procedure in May 2020. Both sites comprised of brick-constructed residential dwellings surrounded by mature gardens laid with areas of amenity grass, introduced shrubs and hard standing. Site B was made up of six semi-detached houses and two number large four-terraced houses and Site C seven semi-detached houses and one number large four-terraced house.

Sites B & C typical semi-detached houses

Sites B & C typical terraced house

The Covid-19 outbreak and the subsequent UK government-imposed lockdown measures in England directly impacted on the possession dates for both sites. Works could not start as planned. Possession of Site B was finally given in late December 2020 for a start on site in January 2021.

At this stage it was not clear how the coronavirus pandemic would impact on timescales for Site C, hence this case study is focused on Site B only.

Site B measures approximately 0.47 hectares and is located to the south west of Ockford Ridge and the central recreation ground. The site comprised of 14 dwellings which were set within a cul-de-sac. The surrounding area was primarily residential in character. The north western site boundary formed part of the edge of the Ockford Ridge development and backed onto Eashing Cemetery.

Scope of demolition works: 1. Clearance of rubbish, boundary and garden fencing in disrepair, timber decking, outbuildings, green garden waste and overgrown trees, shrubs and hedges. Below photos of the site pre-possession.

  1. Removal of asbestos contaminated materials from the houses and outbuildings.

During the breaking out of concrete paths around the houses, we uncovered asbestos in the form of shuttering to the underside of the concrete slabs.  Works were immediately stopped pending sampling and testing.  The laboratory report confirmed the presence of asbestos cement. The contaminated concrete and hardcore underneath were removed from site.

  1. Grading the site generally for a level working platform to accommodate mobile elevated working platforms, 40-yard RORO’s and demolition traffic. Roof tiles, hanging tiles and soffits were to be stripped by hand under the supervision of an Ecological consultant. Soft spots in the ground were excavated and filled with imported sub-base material and thoroughly compacted. Timber bog mats were laid as stable working platforms.

Winter 2020-21 saw rainfall well above average. Total rainfall was 207.9mm with 156.8mm in 2019-20, 150mm in 2018-19 and 206.8mm in 2017-18.

There was a very low number of known roosting bats, and the Ecological consultant, under a Low Impact Class Licence, considered it was not necessary to strip the entire roofs but just a meter wide strip along all roof edges along with any lead flashing, hanging tiles and porches.

  1. Soft Strip and Demolition of houses, outbuildings and external structures to ground level, breaking up ground bearing floor slabs, foundations and hardstanding in their entirety.
Ockford Ridge
  1. Removal of all other demolition arisings from site. Salvage and recycling of arisings wherever possible including bricks, roof tiles, timbers, doors and floorboards.
  1. Leave a clean and relatively level site on completion. The ground was raked to aid with water drainage.
Ockford Ridge

Demolition was carried out in a primarily residential environment. A permanent banksman was employed by Dorton Demolition to provide safe access and egress for site traffic throughout the duration of the project. His was also responsible for assisting pedestrians and especially children to understand the site safety measures and diverted routes to the bus stop and road junction whenever practically possible. Access to the bus stop and public footpaths was maintained at all times.

Site traffic routes and times were coordinated with school routes, travel routes and peak travel times of local residents and schools. Timing and sequencing of heavy goods vehicular movements was successfully co-ordinated to avoid peak times for School drop off and pick-ups. Parking of all our vehicles was inside the site confines with no vehicles parked on pavements and adjoining roads.

Wheel washing and road sweeping facilities were provided on site and managed on a daily basis. A water spray system provided regular dampening down for dust control.

Despite the challenges caused by the coronavirus pandemic and especially having to operate a Covid-secure site, coupled with Winter 2020-21 extreme weather conditions, Dde completed the demolition works on time.

Construction work at Site B is now well underway with no obstructions encountered in the ground.