Stainless Steel in the Built Environment

REFLECTING ON MILTON KEYNES

In Spring 2022 Hotel La Tour in Milton Keynes opened to critical acclaim as one of the most impressive architectural projects completed over the Covid 19 pandemic Standing thirteen stories high, the hotel is the tallest structure in the area and has panoramic views of both the city and open fields and spaces

Constructed from ninety tonnes of 1 5mm 316L UltraMarine Polished stainless steel the building is stunning and reflects the excellent use of stainless steel in the built environment

Lensi Photography

The use of reflective stainless steel finishes is not new in an architectural setting There are many examples from buildings clad in this finish from Dubai to Birmingham and now Milton Keynes joins them with a project that is both aesthetically pleasing and providing a surface that will withstand urban contamination with the correct cleaning regime.

Like all construction projects, limiting the cross contamination of ferrous on site when the building is being finished and fitted out can be a challenge Concrete splash is also something to avoid when the infrastructure is being dug out and developed but with the quality team on site inspecting for issues such as these any affected panels were able to be either cleaned or quickly replaced

The UltraMarine finish is produced with polishing mops and compounds with a technique that minimises the mechanical mop marks for the final finish With reflectivity measuring 63 > 70% on the 316L 2B substrate the consistency of the finish made it an ideal finish to ensure visual matchability on the structure as a whole

Project managing such a large project can be time consuming and difficult. With a weekly schedule for sizes and quantities of sheets to be completed for the next stage in the project working closely together with the supply chain is essential

Overall the project was finished three months early meaning the fit out and snag stages could commence in the majority prior to opening

Keeping the finish looking its best is essesntial on such a landmark building and the use of UltraMarine on 316L stainless steel means that the surface is less than 0 05 µm which will help mitigate cross contamination of particles sitting on the surface finish and discolouring

The machines used to polish the material were two Autopullit polishing lines which had been installed during the summer of 2019 as additional lines to expand the Bright Polishing section. Working with a rotating and oscillating polishing mop the finish of each sheet was checked on completion against a control sample piece that had been approved by the architects at the initial design stage This continuity of finish ensured that each panel has the same degree of reflectivity and colour enabling the formation and fabrication of the panels in any order that suited the construction of the building

One of the downsides to using such a reflective finish is that scratches on the surface can be ugly and very obvious and spoil the 'wow' factor particularly at eye level. If the scratches are higher up on the building then whilst the may not be visible to the naked eye they do pose a risk for streaking and discolouration if contaminates sit within the scratches and then are flushed with rain wash off. These scratches can also be subject to aqueous contamination where particles in rain, from exhaust fumes or nearby construction are deposited. However once the structure is complete the higher panels are unlikely to be scratched or damaged and those at 'people level' usually have regular inspections as part of maintenance regimes.

Cleaning the external cladding should be done with a mild washing up liquid solution and rinsed well, not rubbed, to avoid streaking and scratching.

Overall the Hotel will be a landmark for many years to come.