GPF Lewis commissioned LSJ Engineering as the structural steel contractor in a building refurbishment. This was the first part of our work at Mortimer St (the second part is this feature staircase).
- Client: GPF Lewis
- Structural detailing by: DMR Structural Ltd
- Job duration: March 2021-January 2022
We are the appointed structural steel contractor to GPF Lewis, the main contractor refurbishing a building in Mortimer St, W1.
This is a very complicated job as the main part of the works is a vertical extension forming a new 5th floor level. The 5th floor of the building is currently the roof of the 4th floor!




We have had to strengthen the existing steel frame at critical points of the current roof level in order to take the new structure’s weight… The total weight of steelwork alone is over 60 tonnes! Some of the new cranked roof beams weigh over 2 tonnes, and the only way to get these to the new level is by lifting them with a mobile crane. GPF Lewis arranged for several weekend road closures to set up a 130 tonne mobile crane and lift the new steelwork into place.
Here are some more of our photos and, excitingly, some drone footage taken by GPF Lewis! You can find their write up of the project here. We hope you’ve found this post interesting – if you’d like to read about our feature staircase work on the same project, click here.






Are you interested in commissioning steel work from LSJ Engineering?
We are available for steel work projects! Get in touch here or email info@lsjeng.co.uk. Alternatively, phone us on 01702 290 585. You can find more of our structural steel work projects, including other vertical extensions, here. We look forward to hearing from you.
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