Vertical Extension at Mortimer St, Mayfair, London (Mortimer St Part One)

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).

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!

crane and steel work against sky
bird's eye view of the ground from vertical extension work at Mortimer St, London
crane moving steel bar at Mortimer St, London, as part of steel works and vertical extension
crane and steel work being moved at a vertical extension in Mortimer St, London

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.

view of a vertical crane as part of steel work at Mortimer St, London

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.

Steel Staircase for WeWork, Blackfriars Bridge, London

LTB appointed us to design a basement-to-ground-floor steel staircase at a new WeWork office just south of Blackfriars Bridge, London. This is one of a handful of jobs we’ve done for LTB at WeWork offices over the years (here are the others!).

  • Client: LTB
  • Structural detail by: Mark Ebbs
  • Job Date: December 2020

The staircase needed to span over 9 metres, without support posts. This is normally achieved with an off-the-shelf structural steel section such as channel or box section. In this case, however, the stringer had to look as slim as possible. Furthermore, it could be no wider than the balustrade bolted to it. Our team achieved the desired specifications by fabricating a hollow box section from 15mm plates, welded together to make a section size of 400mm x 75mm. The plates were fully welded together to give the strength required. The welds were ground flat to achieve a clean look.

Each stringer was made in two sections and spliced back together on site before erecting. Here is the staircase in our workshop:

Each stringer, once assembled, weighed over 800kgs! We took great care to avoid damaging the finishes. Roustabout lifting gear erected the stringers.

The balustrade is bolted directly to the top of each stringer. Because it needed to fit perfectly, we assembled the stair and made the balustrades on the stringers in our workshop. Then we dismantled it all and sent it to be powder coated by Mulberry and Pier.

We also delivered a raised floor area and ramp balustrade for the ground floor, in the same style. We delivered and completed the works in plenty of time before handover. There was also minimal touching up of the paintwork!

What do you think of the finished staircase?

Note: you can click on each photo to enlarge it.

Interested in commissioning a steel staircase from LSJ Engineering?

We are open for commercial steel work! Get in touch with our team here or email us on info@lsjeng.co.uk. Alternatively, call 01702 290 585. We look forward to hearing from you! You can view write ups of our other staircase projects here.

Steel Staircase at Project Q, Thames Barrier, London

LSJ Engineering built a steel staircase for Project Q at London’s Thames Barrier in autumn 2020.

Construction management company Chisholm and Winch employed us to design, supply and fit a steel staircase to the new Thames Barrier control building in south east London. Balfour Beatty. constructed the new Thames Barrier building.

This was a simple stair… except that the half landing had to be radiused on-plan, in order to match the reinforced concrete (RC) frame of the adjacent wall. Following an electronic laser survey of the curved RC wall, we built the stair to fit. Furthermore, Chisholm and Winch needed to ensure that the build up of insulation and plasterboard, applied to the RC, perfectly matched the wall. Bearing this in mind, we trial-built the stair at our works in Shoeburyness, Essex. This allowed us to check that the rolled stringers perfect fit the laser-cut landing plates, and fit the wall without gaps or clashes.

Once powder coated a rather bright yellow off-site, the stair was delivered and fitted without any issues!

What do you think of the finished product? Although a complex job, our team worked brilliantly to ensure we fulfilled our brief.

Do you require a steel staircase for your construction project?

We are open for commercial steel projects. Contact the team here, or email us via info@lsjeng.co.uk. Alternatively, you can phone us on 01702 290 585. You can view write ups of our other staircase projects here.

External Staircase Replacement in Harrow

ACAI Group commissioned LSJ Engineering to work on a commercial property in Harrow, Greater London. The property included a badly corroded external staircase, so our team designed and fitted replacement.

The existing stair (probably in excess of 20 years old!) did not conform to current regulations. Unfortunately, the replacement stair did not meet regulations either, due to space restrictions. Permission was, therefore, granted by Building Control to replace ‘like for like’ in terms of tread goings and risers.

At the time of this project, our in-house drafting facilities were very busy on other projects, so the design work and drawings were carried out by Sam Thewsey of DSD Ltd.

This was an office access stair, so we carried out the removal and replacement over 4 long days, partly over a weekend in order to minimise disruption to the businesses.

The new stair stringers, treads and balustrade were hot dip galvanized for durability.  What do you think of the finished staircase?

Note: you can click on the images to enlarge them.

An external staircase replacement in Harrow: https://lsjengineering.co.uk/2021/01/04/external-staircase-replacement-in-harrow/

Do you require a replacement external staircase?

We are open for commercial staircase work. You can get in touch with the team here, or  email info@lsjeng.co.uk. Alternatively, phone us on 01702 290 585. We look forward to hearing from you! You can view write ups of our other staircase projects here.

Feature Staircase for Xero, Kings Cross, London

Denton Associates commissioned LSJ Engineering to design a feature staircase for an office fit out for Xero in Kings Cross.

The challenge on this job was that the stair ran from 7th to 8th floor levels, and the only access was via a 2.5m long lift. This meant that all the stair stringer and balustrade sections had to be less than 2.5m in length! They still required powder coating off site.

Our team designed the stringers to have neat joints. This allowed them to be bolted together once we got them to the correct level. It also ensured the stingers are as strong as if they were on one piece. The half landing support posts formed an ‘X’ to reflect the end client’s logo.

The perforated balustrade panels were bespoke, punched to form neat borders around each balustrade, while the copper handrails were fitted by others.

LSJ also undertook the demolition works to form the stair void opening in the 8th floor slab. We subcontracted to Evolution Enabling of Rayleigh, who installed a crash deck, saw cut and removed the slab, which was equally as challenging as the stair install.

A feature staircase for Xero at King’s Cross, London: https://lsjengineering.co.uk/2020/12/29/feature-staircase-xero-london/

Are you interested in commissioning a feature staircase from LSJ Engineering?

We are open for commercial steel and staircase work! Get in touch with the LSJ team here, email info@lsjeng.co.uk or call 01702 290 585. You can view write ups of our other staircase projects here.

Feature Steel Staircase for Harmony, Oxford St, London

L&J Contracts of Rayleigh commissioned the LSJ Engineering team to design, supply and fit a feature steel staircase to a new Harmony flagship store in Oxford Street, central London. Did you know that Oxford Street is one of the busiest shopping streets in Europe? We’re used to large commercial jobs, but it’s not every day we get to work in such an iconic location! It made a nice change from basements and new builds…

The staircase was to have an industrial look. Our team had an assigned budget and therefore designed the staircase accordingly. We suggested constructing a steel stair and balustrade. Furthermore, we suggested it should be powder coated, with a stainless steel, horizontal tensioned, wire infill.

Construction and installation was a smooth process, with the project completed to our satisfaction.

What do you think of the final ‘look’ of the staircase?

Note: you can enlarge the images by clicking on them.

Thinking of commissioning a feature steel staircase?

LSJ Engineering is available for commercial steel work projects! Get in touch with the team here, or email info@lsjeng.co.uk. Alternatively, phone us on 01702 290 585. We look forward to hearing from you! You can view write ups of our other staircase projects, including work for WeWork and Xero, here.

Secondary Steelwork for Comast Construction Ltd, City Island, East London

The LSJ Engineering team worked on this secondary steelwork project for over two years, for Comcast Construction.

We carried out various secondary steelwork structures to a site in East London for Comast Construction, who were themselves under contract to Ballymore Group.

The works partly consisted of steel roof and staircase structures which were connected to a reinforced concrete building. Our biggest challenges were our extremely difficult access problems!

We achieved the safe installation of the new roof structure by using a truck-mounted access platform and a 5 axle Speiring mobile tower crane. These were from City Lifting. The internal steelwork and stair structures were erected using manual lifting gear, such a chain blocks and scissor lift access platforms.

Take a look at the plans and construction process below! What do you think of the finished work?

Note: you can enlarge the images by clicking on them.

 

Are you looking for secondary structural steelwork for a commercial property?

We are available for structural steelwork projects! Contact us here, email info@lsjeng.co.uk or call 01702 290 585. You can find more of our structural steel work projects here. We look forward to hearing from you!

Steel Feature Staircase at Berners St, Westminster, London

Oktra, an office fit out company, commissioned the LSJ team to design, supply and fit a feature staircase for their Berners St project in Westminster, London. The staircase’s design complicated this job somewhat, but we’re pleased with the result!

  • Client: Oktra
  • Modelled by: Mark Ebbs
  • Job date: May 2020

This stair is unusual in that the stair stringers extend to full height in order to form balustrades, with handrails fixed to the inside face. The unique design made installation quite challenging! This was because the large powder-coated sections had to be manually taken through a double door on site, then around internal doorways, and finally lifted down to basement level. All without damaging the finishes…

The area in which the stair was installed was very tight, so we trial erected the stair in our workshop. During the trial we discovered a major problem fitting the treads. Because the stair was destined for such a small space, had we not spotted the issue until we arrived on site in Westminster, we would not have been able to install it. As it was, we changed a few design details at headquarters. In fact, installation went very smoothly and ahead of programme. What do you think of the completed staircase?

Note: you can enlarge the images by clicking on them.

Are you looking for a feature steel staircase for your commercial property?

Our team is available for new projects. Get in touch here or email info@lsjeng.co.uk. Alternatively, call 01702 290 585. We look forward to hearing from you! You can view write ups of our other staircase projects here.

External Basement Access Staircase at Old Burlington St, Mayfair, London

ACAI Group commissioned us to replace a badly corroded external basement access staircase at their property in Old Burlington Street in Mayfair, London.

  • Client: ACAI Group
  • Modelled by: Mark Ebbs
  • Job date: June 2020

The existing staircase, which was probably over 30 years old, did not conform to current safety regulations. Due to space restrictions, nor could the replacement stair. Building Control granted permission, therefore, to replace ‘like for like’ in  terms of tread goings and risers. This can happen with older buildings.

Our new stair stringers and balustrade were powder-coated in an external grade finish before instalment. The treads, meanwhile, were hot dip galvanized rather than powder-coated, for durability.

What do you think of the finished basement access staircase? We’re pleased with the results! Designing and fitting staircases in ‘difficult’ circumstances, such as when space constrictions do not allow us to work to standard safety specifications, can be difficult. It’s always gratifying when these projects go well!

Note: you can enlarge the images by clicking on them.

external access steel staircase by LSJ Engineering, at Old Burlington St, Mayfair, London
drawing of steel basement access staircase by LSJ Engineering, at Old Burlington St, Mayfair, London
steel basement access staircase by LSJ Engineering, at Old Burlington St, Mayfair, London
steel staircase by LSJ Engineering, at Old Burlington St, Mayfair, London
steel staircase by LSJ Engineering, at Old Burlington St, Mayfair, London
steel staircase by LSJ Engineering, at Old Burlington St, Mayfair, London
steel staircase by LSJ Engineering, at Old Burlington St, Mayfair, London
steel basement access staircase by LSJ Engineering, at Old Burlington St, Mayfair, London
steel basement access staircase by LSJ Engineering, at Old Burlington St, Mayfair, London

Thinking of commissioning a staircase or structural steel work from LSJ Engineering?

We are open for commercial work, including basement access staircases. Get in touch with our team here, email info@lsjeng.co.uk or call 01702 290 585. We look forward to hearing from you! You can view write ups of our other staircase projects here.

Internal Fire Escape Stairs for WeWork East Road, London

LTB enlisted the LSJ Engineering team to create some internal fire escape stairs for WeWork’s building in East Road, London. LTB is contracted to refit offices for office company WeWork. We have, therefore, done a few jobs on WeWork sites (you can see them here!). Usually we do ‘regular’ staircases for the main building, but on this project our brief concerned internal fire escape stairs.

  • Client: LTB
  • Modelled by: Mark Ebbs
  • Date: June-July 2018

The building’s general layout dictated our design constraints on this project. The stair runs up through voids in the building’s concrete floors (formed during the building’s construction). The stair stringers are supported at each level from floor slabs. Half landings, meanwhile, are supported on posts. You can see the plans for the fire escape in the gallery below.

A 3D survey was taken of the whole stair void area. We designed the entire stair, which has a balustrade with perforated sheet infill panels. The stair was powder coated off-site prior to installation.

In order to produce the stair stringers, Pegasus Profiles laser cut one piece each from steel plate. Pegasus Profiles carried out this part of the project because they have CNC machines large enough for the job!

Once the stair stringers and powder coating were complete, all that remained was installation! What do you think of the finished fire escape?

Note: you can enlarge the images by clicking on them.

internal fire escape stairs with scaffold at WeWork, East Road
drawing of nine story fire escape by LSJ Engineering
drawing of nine story fire escape by LSJ Engineering

Considering commissioning internal fire escape stairs from LSJ Engineering?

We are available for fire escape construction work! Get in touch here, or email info@lsjeng.co.uk. Alternatively, you can phone us on 01702 290 585. We look forward to hearing from you. You can view write ups of our other commercial staircase projects here.