View source for The Lexicon, Bracknell, Berkshire

==Article in [http://www.newsteelconstruction.com/wp/wp-content/uploads/digi/NSCmarch16digi/index.html#/10/ NSC March 2016]==
{{#image_template:image=File:The_Lexicon-1.jpg‎|align=right|wrap=true|caption=Visualisation of a Lexicon mall|width=400}}
'''New town makeover'''<br>
Steel [[Construction|construction]] is playing a leading role in a £250M [[Retail_buildings|retail scheme]] that will transform a large swathe of Bracknell town centre.<br> 

One of the new towns built after the Second World War to ease inner city congestion and provide war weary families with modern housing, Bracknell is now getting a much-needed makeover.

[[Construction|Construction]] work is now under way on Phase 2 of a new retail quarter in the town centre designed by BDP and Chapman Taylor for Bracknell Regeneration Partnership, a joint venture between Legal & General and Schroders along with Bracknell Forest Council. Working on behalf of main contractor Mace, Severfield is undertaking all of the structural steelwork for phase two, as well as [[Construction#Installation of metal decking|installing metal decking]].

Known as The Lexicon, the scheme is a shopping and [[Leisure_buildings| leisure destination]], which promises a vibrant mix of brands and experiences and a high quality mix of shops and venues connected in a pedestrian-friendly environment.

Phase one of the scheme consisted of the [[Construction|construction]] of a steel-framed Waitrose [[Retail_buildings#Supermarkets|supermarket]] that was completed in 2011. Acting as one of the anchors for the overall scheme, this structure was [[Fabrication|fabricated]], supplied and [[Construction#Steel erection|erected]] by Billington Structures.

Phase two, which kicked off on site in 2015 covers an area of 60,000m<sup>2</sup> and comprises two department stores, [[Retail_buildings|retail units]], restaurants and cafes, a 12-screen [[Leisure_buildings#Theatres and auditoria|cinema]], [[Car_parks|multi-storey car park]] and 92 [[Residential_and_mixed-use_buildings|apartments]].
{{#image_template:image=File:The_Lexicon-5.jpg‎|align=left|wrap=true|caption=Billington Structures [[Construction#Steel erection|erected]] the Phase one Waitrose store|width=300}}
Prior to Mace starting on site, the demolition of the site’s 1960s and 70s built shopping district had been completed. Early works included a huge earthmoving operation to level the sloping topography. Piling was then undertaken and this work has continued alongside the steel programme, although in areas where it had been completed, Severfield was able to begin [[Construction#Steel erection|erecting]] the new structures.

Mace Project Director Andrew James says six of the new structures within the scheme are [[Braced_frames|steel-framed]] buildings and the material was chosen for its [[Long-span_beams|long-span]] qualities and [[Retail_buildings#Speed of construction|speed of construction]]. Another important consideration is steel’s [[Retail_buildings#Flexibility|flexibility and adaptability]], which allows for different shop configurations to be installed if and when the client changes or retail requirements alter.

A further building within Phase two is also [[Braced_frames|steel-framed]] and this is a nine-storey structure dating back to the 1980s (pictured Below). Originally designed as an office block on top of a two-level retail [[Residential_and_mixed-use_buildings#Podium structures|podium]], the structure is being renovated to accommodate [[Residential_and_mixed-use_buildings|residential units]] on the upper seven levels. The original [[Residential_and_mixed-use_buildings#Podium structures|podium]] has been demolished and approximately 300t of new steelwork will be [[Construction#Site bolting|bolted]] to the existing tower to form a much larger two-level [[Residential_and_mixed-use_buildings#Podium structures|podium]] that will accommodate an H&M store as well as numerous food outlets.

The six new steel structures being [[Construction#Steel erection|erected]] by Severfield consist of two anchor department stores (Marks and Spencer, and Fenwick), and four other [[Retail_buildings|retail blocks]], one of which incorporates the [[Leisure_buildings#Theatres and auditoria|cinema]] complex. The two 7,400m<sup>2</sup> department stores are situated either side of the concrete-framed multi-storey [[Car_parks|car park]], and because they link directly into the facility their designs have dictated the latter’s.

The M&S store is based around a 9.6m × 9.6m steel [[Concept_design#Floor grids|grid pattern]] that consists of a basement plant level and loading dock with two trading floors above. Each trading floor has a 6m floor-to-ceiling height that allows it to tie into alternate [[Car_parks|car park]] floors, as the latter structure is based around a 3m floor-to-ceiling height.

M&S was the first building to be [[Construction#Steel erection|erected]], as this part of the site’s footprint was the first to have its groundworks completed. “This area had a very steep slope that had to be infilled,” says Mr James. “Plus getting the anchor stores [[Construction#Steel erection|erected]] first was important as they have the longest fit-out programmes.”
{{#image_template:image=File:The_Lexicon-4.jpg‎|align=left|caption=Bracknell’s retail offering will be more than doubled|width=600}}
Just before M&S was fully [[Construction#Steel erection|erected]] another Severfield [[Construction#Steel erection|erection]] gang had begun on the adjacent Fenwick store. “Using a number of 80t-capacity [[Construction#Mobile cranes|mobile cranes]] and up to five gangs of erectors we have staggered the steel programme so at least two buildings are being progressed at any one time,” explains Severfield Project Manager Robin Hamill.

The Fenwick store is based around a slightly larger 11.4m steel [[Concept_design#Floor grids|grid pattern]] incorporating three trading levels with an additional 1,400m<sup>2</sup> future expansion zone. With three trading floors to fit into a building with a similar height to the M&S store, and with the need to tie into the adjacent [[Car_parks|car park]], the building has floor-to-ceiling heights of 5m. To help reduce the floor depth the [[Service_integration|services are integrated]] within 750mm deep fabricated [[Steel_construction_products#Plate girders|plate girders]] with 1,200mm wide × 450mm deep notches in the ends and 300mm diameter holes in the web.

The different floor-to-ceiling heights and number of floors within the anchor stores was client driven,” explains Arup Project Engineer Ewan Smith. “It did mean some redesign work was necessary on the [[Car_parks|car park]] to align the floors. “In order to keep the department stores’ overall heights similar the Fenwick store has [[Service_integration|integrated services]] within [[Steel_construction_products#Cellular beams|cellular beams]], while height wasn’t an issue for the M&S structure so it has fewer floors and large services voids between floors.”

The project’s largest structure is known as building five, which measures 100m x 90m. It accommodates two levels of retail units, based on a typical 7.8m × 13.5m [[Concept_design#Floor grids|grid]] with the [[Leisure_buildings#Theatres and auditoria|cinema]] located above on the third level. Some flexibility has been achieved within the retail floors as an extra [[Single_storey_industrial_buildings#Mezzanines|mezzanine]] floor has been accommodated within the area to be taken by a Next store. “The large retail [[Concept_design#Floor grids|grid]] works well with the [[Leisure_buildings#Theatres and auditoria|cinema]] above,” adds Mr Smith. “The [[Leisure_buildings#Theatres and auditoria|auditoriums]] have to be column-free spaces and so their column locations have dictated the [[Concept_design#Floor grids|pattern]] below in the retail levels.”

Completing the steel package are two more steel [[Braced_frames|braced frame]] [[Retail_buildings|retail structures]] known as buildings four and eight. The former will accommodate double-height units with a [[Single_storey_industrial_buildings#Mezzanines|mezzanine]] capability based around a 7.8m × 10.2m [[Concept_design#Floor grids|grid]], while eight is similar in design except it has a larger 7.8m × 13.5m [[Concept_design#Floor grids|grid pattern]].
<gallery widths=300px heights=210px> 
Image:The_Lexicon-2.jpg|The Fenwick anchor store has three trading floors
Image:The_Lexicon-3.jpg|The [[Leisure_buildings#Theatres and auditoria|cinema]] block takes shape
</gallery>
<br>
The final [[Braced_frames|steel-framed]] retail block [building eight] is situated on a plot separated from the main scheme by the existing pedestrianized High Street. This part of The Lexicon is known as Charles Square and it will also include an adjacent concrete structure.

“Logistics is a key issue as the site is very congested with numerous trades and surrounded by busy roads, the existing town centre retail area, a police station, council offices, a library and residential properties,” says Mr James. “When it comes to working at Charles Square, logistics will be even more challenging as one of the buildings is landlocked by the existing pedestrianized streets which remain open to the public throughout the development. This effectively cuts the project into three.  There is no direct road access to one of the buildings and so [[Fabrication#Handling and transportation|deliveries of materials]], such as steelwork, will have to be made through an existing structure that has been part-demolished and will form part of building eight in the completed scheme. We will use an online just-in-time delivery system to aid this work.”

The project will utilise a variety of [[Facades_and_interfaces|cladding]] materials including brick, timber, aluminium, coloured glazing, and gold/silver coloured copper cladding. The Fenwick store in particular will stand out as it will be clad in 5mm-thick perforated anodized aluminium [[Facades_and_interfaces#Rain screen cladding|rain screen cladding]], which will be backlit. This system is bespoke and has been developed specifically for this scheme.

The pedestrianized streets within the scheme will be spanned by [[Facades_and_interfaces#Steel in atria and canopies|canopies]] formed with steel and glulam beams covered with ETFE.

Another key concept for the scheme is the public realm design, which forms part of the ‘greening of Bracknell’ to transform the character of the existing town. A large open space, which could be used as an outdoor auditorium, is being constructed between the M&S store and Waitrose.

The Lexicon is due to open in spring 2017.

{|class="wikitable" width="400"
|-
|'''Architect'''||BDP/Chapman Taylor
|-
|'''Structural Engineer'''||Arup
|-
|'''Steelwork Contractor'''||Severfield
|-
|'''Main Contractor'''||Mace
|-
|'''Main Client'''||Legal & General/Schroders
|}

[[Category:Case studies - Retail buildings]]