A variety of subflooring solutions specified for mental health revamp
Bostik products were used on the redevelopment of St Ann's Hospital
The redevelopment of St Ann’s Hospital, a multi-purpose healthcare campus in Tottenham, included a new, purpose-built mental health inpatient building.
Designed to transform the care of patients and the working conditions of staff, the 74-bed mental health facility involved extensive redevelopment of the previous wards on the site and is rated BREEAM ‘Excellent’ for sustainability.
Bedford-based flooring contractor, Blade Flooring, was appointed to install the floor coverings throughout the redevelopment, and turned Bostik for its technical specifications and subfloor preparation products.
The project was large and varied, with the subfloors in the unit’s three blocks having different requirements that needed to be treated in unique ways.
For example, some parts of the subfloor were made of concrete and others were made of plywood.
For the concrete areas, the Bostik team advised that Blade Flooring apply its HYTEC E570 ONE COAT damp-proof membrane (DPM) to suppress the residual moisture in the subfloor, followed by GRIP A526 UNIVERSAL PRIMER and SCREEDMASTER SL C540 FLOW smoothing compound, which provides improved workability and excellent flow characteristics.
For the plywood areas, once they had been primed, Bostik specified SCREEDMASTER SL C530 FLEX, a fibre-reinforced, heavy-duty smoothing compound that is particularly suited for application onto wooden floors.
This varied approach continued into Blocks G and H where, again, some parts of the subfloor were concrete and others were plywood.
In this case, however, there were a number of hydration cracks in the surface of the concrete. These was overcome with Bostik RENO P520 EASY, a crack repair system including a solvent-free, 2K repair resin and stitching pins.
RENO P520 EASY can be mixed easily within its containers and dries in just 30 minutes.
Once the cracks had been filled in, the team primed the surface with GRIP A936 XPRESS, Bostik’s water-based primer with high grip and a fast-drying time, before smoothing it with SCREEDMASTER SL C530 FLEX.
And Block B required yet another approach, as there was Lytag screed present in parts of the subfloor.
In some areas, this could be worked around, while in others it was so damaged that it needed to be removed.
In the areas where a new screed was required, Bostik advised Blade Flooring to apply a slurry mix of TECHNIS C720 FLOW – a pre-blended, rapid-fluid screed, mixed with Bostik SBR – a co-polymer latex that toughens, waterproofs, and improves the chemical and abrasion resistance of screeds.
Once the slurry mix was applied to the prepared substrate, TECHNIS C720 FLOW was again used to reinstate the levels where the Lytag screed had been removed.
Once applied, TECHNIS C720 FLOW can receive moisture sensitive floor coverings in as little as seven days.
This product, with its rapid drying performance, helped to keep the programme on track.
The team then primed the surface with GRIP A936 XPRESS, before a layer of SCREEDMASTER SL C540 FLOW was applied to smooth the subfloor ready for the adhesive and floor coverings.
Bostik’s technical advice and subfloor preparation products enabled Blade Flooring to navigate a complex and demanding installation, ensuring they could install the floor coverings to the highest standard, on time for the hospital to open its doors to patients.
Ian Dennis, technical specification manager at Bostik, said: “This was a large project that involved modernising a sprawling 1950s hospital.
“It was therefore necessary to advise Blade Flooring on a range of different subfloors, which were in various states of disrepair and had a number of requirements.
“With a project like this, you don’t know what you’re going to find until you lift the flooring and, in this case, there was everything from Lytag screed to old pipework.
“However, once our team had inspected the site, we presented Blade Flooring with a set of recommendations for how to prepare the subfloors and this enabled them to get the job done.”
James Hall, business development director at Blade Flooring, added: “This was a demanding project with many challenges due to the sheer size of the building, as well as its age.
“You are inevitably going to face challenges on such an old site, but with Bostik’s experience and products, we were able to meet these challenges and install the flooring on time and to the right quality.”
The new mental health facility is part of a project to create a modern health campus with direct benefits to the local community.
With a sustainable mix of mental health and other services, the St Ann’s Hospital site includes services provided by Moorfields Eye Hospital, Whittington Health community health services, and North Middlesex University Hospital breast screening services.
In the next phase of the development, homes for the local community and an open space for the public will also be created.