Structural Renovations Limited commenced work on site at Westminster Court in September. The project consists of concrete repair, corrosion management and protective coatings to the 9 storey, purpose built residential block, which over looks the sea.
The reinforced concrete had been previously repaired and existing repairs had began to fail, combined with ‘new’ defects that had presented themselves.
The blocks close proximity to the sea has accelerated the deterioration of the concrete due to the effects of airborne chloride contamination and it was therefore proposed that a form of corrosion control should be adopted to prolong the life of not only the repaired areas but the concrete in its entirety.
The working areas have been scaffolded and clad with debris netting, to provide a safe and efficient mean of access.
Following a visual and hammer tap survey, all defective areas of concrete were broken back to sound substrate and the reinforcement treated with a cement rich primer. All prepared and treated areas were then reinstated using a hand placed, polymer modified repair mortar.
The corrosion management system involved drilling and installing vapour phase inhibitor capsules in a grid pattern across all concrete faces. These capsules will release their inhibiting properties over 12-48 months around the reinforcement, providing a passivating protective layer, which reduces exposure to harmful chlorides.
All concrete surfaces are then to be pressure washed to remove dirt and loose materials, followed by the application of a water based primer/adhesion promoter.
Finally, the entire primed area will be protected with a pigmented, elastomeric, anti-carbonation coating.
All products are produced by Sika Limited and this particular system, once complete will provide the client with a 10 year guarantee.
The works are programmed for completion in early November.
Structural Renovations are currently working at Victoria House in London, SW1. Victoria House is a 5 storey residential block completed in 1959. The front elevation is mainly brickwork, whereas the rear elevation extends with concrete access walkways, staircase and access to the basement.
Structural Renovations are employed to carry out extensive concrete repairs to the window cills & heads, walkway soffits, return walls and supporting columns. The defective areas were repaired using Sika MonoTop 615 and then all previously coated areas were treated with SikaGard 675W ElastoColor and all previously uncoated concrete was treated with SikaGard 680S Clearglaze.
The walkway decks, stairs and landings were repaired using Sika MonoTop 630 and were then treated with a reinforced waterproof non-slip coating made up of Sika Bonding Primer, Sikafloor 405, reinforced with Reemat Premium and Sikafloor 420.
Additional works to the front elevation were carried out which included sympathetic colour matched repairs to the front entrance using Remmers Restoration Mortar, replacement render to the gable wall & retaining walls as well as Helifix crack stitching and installation of Helibeams.
Structural Renovations were awarded the contract to complete extensive structural repairs and apply protective coatings to all reinforced concrete within the landmark structure, known as The Observer Building, in Hastings town centre.
The building was originally constructed for the publishers and printers, F. J. Parsons, in 1924 and was designed by the Hastings architect, Henry Ward.
The building was subsequently used by The Observer Newspaper as both a printworks and its administrative centre, until vacating in 1985. The building has remained empty and neglected in the years between, which has allowed significant deterioration to be caused to the entire building fabric and in particular the reinforced concrete structure.
A number of surveys have been conducted over the years, when various parties showed an interest in taking on the building and each survey shows the increasing damage caused, in the main, by water ingress.
The building was finally purchased by White Rock Neighbourhood Ventures in late 2018, who, together with the assistance of various funders, intend to bring this impressive building back to life and utilise the enormous space available.
Our works have involved surveying all concrete surfaces to identify the full extent of defective concrete, before its removal back to a sound substrate. All exposed reinforcement is carefully prepared prior to be in treated with a proprietary primer. The prepared areas are reinstated using a cementitious, polymer modified repair mortar.
Due to the sheer size of the structure internally (in excess of 5,000m²), it was decided that the protective anti-carbonation coatings would be applied by airless spray equipment, which was purchased specifically for this project and has enabled the process to be sped up considerably.
During the works approximately 15 tonnes of repair mortar will be used and over 2,000 litres of anti-carbonation coatings.
It is testament to the original design and construction of this building, which was left to decay for so long that its repair was viable, and demolition was not necessary.
The external elevations of the building are hoped to be completed as part of a separate phase, which will be carried out in the near future.
The 4th and 5th floors are currently being refurbished at Devon House and Structural Renovations have been employed to carry out the concrete repairs.
Devon House is situated on Great Portland Street and is part of the Langham Estate portfolio.
The floor slabs have been constructed from clinker concrete and steel filler joists. The filler joists have corroded and caused the concrete and plaster to crack and spall.
The defective concrete was removed from around the filler joists, the corrosion was removed by mechanical wire brushing and then the cleaned steel was primed with two coats of Fosroc Nitoprime Zincrich Plus. A galvanised mesh was fixed over the exposed steel and the concrete was reinstated with Fosroc Renderoc HB.
Structural Renovations have been working at Hallam House on Hallam Street since late 2018. The building is part of the Langham Estate portfolio and we have been working closely with the Estate’s Principal Contractor, Millane Contract Services and the Consulting Engineer, Jacobs.
The building is currently being refurbished and upgraded. In the basement plant rooms and brick vaults we have installed a new waterproof render using Flexcrete materials. Concrete repairs and anti-carbonation coatings have been carried out within the rear lightwell to the window heads and cills.
Internally, the existing lift was removed, and we were required to carry out extensive repairs to the staircase that wraps around the lift core. Existing supporting steel work was cut out and the landings and strings were repaired back to the original surface profile as required by the contractor installing the new glass lift.
Structural Renovations have secured a 12 week project to remove brick slips from a 5 storey purpose built office block in Hove, known as Preece House.
The structure was built in 1980 when the fixing of brick slips (thin sections of brick) was still a relatively popular design feature. This gave the impression of an entirely brick built building, when in fact the slips were adhered, using mortar over the floor plate edges to conceal them, a little like tiling.
Over time the mortar used to affix the slips can fail, either through poor preparation at time of construction, or freeze/thaw activity, if moisture has penetrated behind them. This can lead to failure and the slips falling from the building, causing a significant health and safety risk.
Following a diagnostic survey earlier in the year it was identified that a significant amount of brick slips had failed or were beginning to fail. At this time the building was made safe by removing all loose slips, to reduce the risk to people or property.
A number of remedial actions were considered and in October the decision was taken to remove all brick slips from the building, thus removing the health and safety risk altogether.
The majority of the works is being carried out from scaffolding, which due to the shape of the building is cantilevered in places. Low level areas are being accessed from lightweight aluminium mobile towers.
Following the brick slip removal process, the exposed reinforced concrete substrate is surveyed, to identify if repairs are required. These are being carried out using Flexcrete Monomix, as part of their proprietary concrete repair system.
Once repaired we are contracted to apply Monolevel FC (fairing mortar), followed by the application of Flexcrete Monodex Ultra (pigmented anti-carbonation coating).
Associated works items, such as replacing perished sealants and localised repointing have now also been instructed and it is anticipated that the works will complete in mid-February 2019.