London's office development pipeline looks enormous on paper. Across the City, West End, South Bank, Canary Wharf and other commercial districts, millions of square feet of offices are consented, being redesigned, demolished, retrofitted or marketed for future delivery. But the construction opportunity between 2027 and 2030 is considerably smaller and considerably more complicated than the headline pipeline suggests.
Some of London's biggest future towers are still occupied. Others are already spending years in deconstruction before a new core can rise. Several consented schemes have no publicly confirmed main contractor or major pre-let. At the same time, deep retrofit is taking a growing share of commercial construction activity as developers retain frames, basements and façades rather than automatically demolishing existing offices. That creates two very different office pipelines.
The first is the visible planning pipeline: towers, redevelopment proposals and major refurbishments with permission or advanced designs.
The second is the construction pipeline: projects where occupation, demolition, finance, procurement and programme have aligned sufficiently for real structural work to become credible.
Canary Wharf's commercial district and office buildings. Photo: London Construction Magazine.
While planning consent is often treated as evidence that London's next office boom is ready to begin, London Construction Magazine analysis shows that vacant possession, demolition sequencing, development finance, occupier commitment and contractor procurement lead to a much smaller group of projects capable of reaching substantive construction between 2027 and 2030. The result is not a broad speculative office boom. It is a highly concentrated market combining a small number of ultra-prime new-build developments with an increasingly important retrofit and retained-structure pipeline.
London Office Pipeline 2027–2030: The Real Question
For contractors, asking whether an office project has planning permission is no longer enough. The commercially useful questions are:
• Is the existing building still occupied?
• Has vacant possession been secured?
• Is strip-out underway?
• Has demolition actually started?
• Is the basement or existing frame being retained?
• Is development funding committed?
• Is there a signed pre-let or merely occupier interest?
• Has a main contractor been appointed?
• Does a published "construction start" refer to demolition or the replacement building?
• When will piling, concrete, structural steel, façade, MEP and fit-out packages actually reach the market?
Those distinctions are particularly important in the City of London, where removing an existing office tower can itself take years. A project can therefore generate significant demolition, temporary works and monitoring turnover long before it becomes a new-build office project.
By the Numbers: Major London Office Projects to Watch
| Project | Location | Type / Scale | Position at August 2026 | Credible Workload Window | Key Dependency |
| One London / 1 Undershaft | City of London | c.1.7m sq ft; major new commercial tower | Existing St Helen's Tower being deconstructed; Keltbray involved in demolition | 2028+ main build | Complete deconstruction, development finance and main-build procurement |
| 99 Bishopsgate | City of London | Major office tower redevelopment | Planning secured; substantial existing-building removal precedes replacement structure | 2028+ strongest main-build signal | Deconstruction, vacant possession and final main contractor route |
| 55 Bishopsgate | City of London | Large consented commercial tower | Planning secured; main construction commitment remains less advanced | 2028–2029+ possible | Occupiers, vacant possession, procurement and commercial commitment |
| One Silk Street | City of London / Barbican | c.90,000 sq m office-led redevelopment | Permission secured in 2026; existing asset remains central to programme; contractor not publicly confirmed in research set | 2028–2029 more credible | Vacant possession, demolition and procurement |
| 70 Gracechurch Street | City of London | Large hybrid redevelopment with substantial retention | Planning secured; parts of existing asset remain occupied | 2028+ probable | Vacant possession and detailed delivery strategy |
| 60 Gracechurch Street | City of London | Major new commercial development | Demolition / enabling activity and contractor commitment place it ahead of much of the wider pipeline | 2026–2029 active workload | Demolition-to-main-build sequencing rather than planning |
| 85 Gracechurch Street | City of London | c.30-storey commercial redevelopment | Mace appointed; archaeological and heritage interfaces materially affect programme | 2026–2027 transition | Archaeology, sequencing and distinction between enabling and main build |
| 50 Baker Street | West End / Westminster | c.236,000 sq ft office redevelopment | Contractor-backed programme and demolition progression | 2027 main works | Completion of demolition and transition into main works |
| Holden House | Oxford Street / West End | c.135,000 sq ft redevelopment | Contractor appointed; early activity progressing | 2027 structural workload | Delivery rather than planning certainty |
| Liberty House / Olympia | Kensington Olympia | c.110,000 sq ft office component within £250m mixed-use development | Planning, contractor and hotel occupier evidence create comparatively strong delivery visibility | Early 2027 onward | Mobilisation and complex retained / mixed-use interfaces |
| 10 New Bridge Street | City of London | Deep office retrofit; approximately 73% structural retention reported | Consented retained-structure redevelopment | 2027–2030 retrofit workload | Existing-structure interfaces and detailed retrofit design |
| 1 Embankment Place | Charing Cross / Westminster | Major retrofit; around 90% of existing structure and floorplate proposed for retention | Planning-stage major commercial retrofit | Late-2020s opportunity | Planning, structural integration and occupied-city logistics |
| 8 Canada Square | Canary Wharf | Major existing tower repositioning | Future redevelopment linked to occupier departure and estate repositioning | Late 2020s | Handover, redesign and complex tower conversion |
Methodology note: This is a prioritised construction-intelligence selection rather than a claim that every consented London office scheme will start. Main construction, demolition, enabling and retrofit have been treated separately. Where contractor, pre-let, financing or exact programme information could not be established with sufficient confidence, it has not been presented as confirmed.
2027 Has More Starts, But 2028 Has the Bigger Towers
One of the most useful conclusions from the research is that there are two ways to answer the question: Which year has London's strongest office pipeline? By number of projects with stronger contractor and programme evidence, 2027 currently looks healthier. Projects around Baker Street, Oxford Street, Olympia and several smaller commercial redevelopments provide more visible near-term mobilisation than many of the giant City towers.
But by potential scale of structural construction, 2028 could be much more important. That is when One London / 1 Undershaft and 99 Bishopsgate become far more relevant to the concrete, structural steel, façade, MEP and vertical-transport supply chains — assuming the remaining commercial and demolition dependencies are resolved. Our wider analysis of the London planning pipeline for 2027–2030 reached a similar conclusion: 2027 contains increasingly identifiable committed work, while 2028 contains a much larger conversion opportunity where today's planning and pre-construction schemes could become physical projects.
For estimators, that distinction matters. The contractor looking for demolition turnover may already be interested in a 2028 tower. The structural steel subcontractor may not see the same opportunity until two years later.
One London Shows Why a Crane Does Not Mean the New Tower Has Started
One London (formerly known as 1 Undershaft) is perhaps the clearest example of the problem with conventional office-pipeline reporting. The site is real and major physical work is happening. Keltbray is involved in removing the existing St Helen's Tower, and the future development has planning consent.
But that does not mean construction of the replacement skyscraper is already underway. The existing tower must first be deconstructed. Main-build procurement and development finance then have to align before the replacement structure progresses through its heavy substructure and vertical construction programme. The research therefore places the strongest main-construction signal around 2028 rather than treating today's demolition operation as the new tower start. That distinction also appeared in our investigation of London skyscrapers delayed, redesigned or still waiting to start, where demolition, redesign and structural commencement were deliberately separated.
99 Bishopsgate Has the Same Programme Problem
99 Bishopsgate creates another classic London-office sequencing problem. The redevelopment has planning support, but the existing building cannot simply disappear overnight. Its removal is a construction project in its own right. That creates work for demolition engineers, temporary works designers, structural monitoring specialists, logistics teams and adjacent-asset protection long before the replacement building creates major steel and façade packages.
Some published programmes can therefore appear to show the scheme "starting" while the activity is actually deconstruction. For construction intelligence, the useful date is not when the first operative enters the old building. It is when the replacement structure genuinely enters foundations, basement and superstructure delivery.
55 Bishopsgate: Consent Is Not the Same as Commitment
55 Bishopsgate sits deeper in the risk spectrum. It is a major consented City office opportunity, but the research did not establish the same level of near-term delivery evidence available on projects already moving through demolition or contractor mobilisation. That does not make the development dead. It means contractors should distinguish a strategically important consent from a committed structural construction programme.
Vacant possession, demolition, contractor procurement, financing and occupier confidence can still change the timing materially. For a specialist subcontractor deciding whether to reserve capacity, that difference matters far more than the existence of the planning permission.
One Silk Street Shows How Occupation Can Control Construction
One Silk Street demonstrates another hidden variable in commercial development: the building that is already there. Planning permission can be secured while an existing commercial asset remains occupied and operational. Until vacant possession is achieved, the development sequence cannot simply advance to demolition because the planning document says it can.
The current evidence therefore makes a later start more credible than treating the project as an immediate construction opportunity. This is one of the most important lessons from the entire office pipeline. For some major London offices, the most important construction date is effectively controlled by a lease rather than a planning permission.
Pre-Lets Still Matter, But the Evidence Is Uneven
London's best offices continue to attract occupier demand, but that should not be confused with every future tower having a committed tenant. The research found much stronger occupier evidence on projects already under construction or approaching delivery than across the biggest speculative late-decade towers.
For several major City projects including One London, 55 Bishopsgate, 99 Bishopsgate, One Silk Street and 70 Gracechurch Street, a large signed anchor pre-let was not sufficiently established across the collated public research to justify treating one as confirmed. That does not mean construction cannot proceed speculatively.
Institutional owners can have the capital and confidence to progress without waiting for a single tenant to underwrite the entire development. But on schemes costing hundreds of millions of pounds, occupier confidence remains commercially important because it affects investment decisions, lending, project valuation and the willingness to move from an expensive demolition programme into an even more expensive structural build.
London's Office Boom Is Increasingly a Retrofit Boom
The other major conclusion is that the future office pipeline cannot be measured by counting cranes. Market data reviewed for this analysis shows that refurbishments represented around two-thirds of London office start volume in 2025, while overall start volume was around 4.8 million sq ft, below the recent five-year average of approximately 6.5 million sq ft. That combination tells an important story. London is not simply replacing old office blocks with larger glass towers.
Developers are increasingly asking whether they can retain:
• foundations;
• basements;
• concrete frames;
• slabs;
• structural cores;
• façades;
• or significant portions of the existing building.
Projects such as 10 New Bridge Street and 1 Embankment Place illustrate how important that model is becoming. At 10 New Bridge Street, the development strategy is based around retaining a substantial majority of the existing structure. At 1 Embankment Place, the proposed redevelopment is designed around retaining roughly 90% of the existing structure and floorplate. For the construction industry, this does not necessarily mean less work, it means different work.
Retrofit Creates a Different Specialist Supply Chain
A new office tower begins with a relatively known design proposition. A 30- or 40-year-old structure can contain surprises. Historical drawings may be incomplete. Reinforcement may differ from records. Slab thickness can vary. Existing fixings may not perform as assumed. Material strengths, fire protection, façades and hidden interfaces may all require physical confirmation.
That shifts expenditure towards:
• intrusive structural surveys;
• reinforcement scanning;
• concrete investigation;
• opening-up;
• material sampling;
• load testing;
• pull-out and fixing testing;
• temporary stability design;
• façade retention;
• movement monitoring;
• slab strengthening;
• local steelwork;
• new penetrations and infills;
• core modifications;
• and complete replacement of obsolete building services.
That is why a retrofit pipeline can produce significant construction turnover even when it adds comparatively little new floor area.
Canary Wharf Is Becoming a Repositioning Story
The research also suggests that Canary Wharf's late-decade commercial opportunity should not be viewed simply as another wave of conventional office towers. The estate is increasingly moving towards a broader mixture of life sciences, residential, mixed-use development and major repositioning of existing commercial assets.
8 Canada Square is particularly important. Once the building's current single-occupier phase ends, the scale of its future transformation could create one of London's most technically interesting commercial retrofit opportunities. The opportunity is not merely cosmetic refurbishment. Repositioning a major occupied-era tower for a new multi-use or multi-occupier future can involve major interventions to circulation, services, structure, façades, fire strategy, vertical transportation and internal floorplate organisation.
Meanwhile, developments such as One North Quay already represent active life-sciences-led construction rather than a future pure-office start. That distinction matters when forecasting demand from conventional office contractors.
Projects We Would Not Count as New 2027–2030 Office Starts
The office pipeline becomes artificially large if every project completing after 2027 is described as a future start. Several major developments are already materially under construction or entered their primary build programme before the 2027–2030 window.
Examples identified during the research include:
2 Finsbury Avenue — a major active construction project with substantial occupier commitment. Its future completion workload matters, but it is not a new 2027 start.
Fifty Fenchurch Street — already in substantive delivery. Work continues through the period, but the project should not inflate a future-start count.
99 City Road — main construction begins before the 2027 window, even though major structural, façade, services and fit-out workload continues deep into the period.
55 Old Broad Street — enters its construction programme before 2027 rather than representing a clean future start.
One North Quay — already active as a life-sciences-led construction project and therefore important workload, but not evidence of a new conventional office start in 2027.
Our separate investigation of major London construction projects starting in 2027 applies the same discipline: completion dates, demolition programmes and active schemes should not be repackaged as new starts simply because they remain visible during 2027.
What Contractors Should Watch in 2027
The nearer-term office market is likely to be characterised by a mixture of smaller high-confidence commercial starts, active demolition and major retrofit.
The strongest packages are likely to include:
• demolition completion;
• temporary works;
• basement modifications;
• structural alterations;
• retained-frame investigation;
• concrete and steel interfaces;
• façade procurement;
• and early MEP packages.
This may produce a healthier number of real opportunities than the largest skyscraper headlines alone suggest.
What Contractors Should Watch in 2028
2028 is the year where scale could change materially. If One London and 99 Bishopsgate transition successfully from demolition and pre-construction into foundations and structure, the quantity of major high-rise work reaching the supply chain increases significantly. Projects such as 70 Gracechurch Street, One Silk Street and potentially 55 Bishopsgate could add further demand if occupation, financing and procurement align.
That creates potential pressure around:
• high-rise logistics;
• tower cranes;
• temporary works;
• deep foundations;
• reinforced-concrete cores;
• structural steel;
• unitised façades;
• major electrical capacity;
• HVAC;
• fire systems;
• and vertical transportation.
2029–2030 Is Much Less Certain Than the Skyline Renderings Suggest
The further the programme moves towards 2029 and 2030, the less useful it becomes to assign precise construction dates to today's planning schemes. Projects can redesign. Developers can sell. Tenants can choose alternative buildings. Financing conditions can change. Retrofit can replace demolition. Existing occupiers can remain longer than anticipated.
That means 2029–2030 should be treated as an opportunity window rather than a guaranteed start schedule. Ironically, some projects that have not even entered today's most prominent pipeline could reach site before schemes that already have permission. A smaller development with vacant possession, committed funding and an occupier can move faster than a million-square-foot tower carrying unresolved commercial dependencies.
Where the Biggest Supply-Chain Opportunities Sit
Demolition and deconstruction
One London and 99 Bishopsgate demonstrate how future office schemes can create substantial demolition turnover before the replacement building begins. High-rise deconstruction requires engineered sequences, monitoring, lifting, protection, temporary restraint and extremely controlled logistics.
Structural investigation and temporary works
Retained-frame projects such as 10 New Bridge Street, 1 Embankment Place and other deep retrofits generate a different opportunity: verifying what already exists before design assumptions become construction decisions.
Concrete and structural steel
The largest late-decade opportunity remains the City tower cluster. If One London, 99 Bishopsgate and other major schemes enter structural construction close together, the amount of high-rise frame work becomes commercially significant even though the overall number of projects remains relatively small.
Façades
Ultra-prime offices demand increasingly sophisticated envelope systems: high-performance glazing, unitised façades, solar control, airtightness, retained-façade interfaces and demanding architectural tolerances.
MEP and commissioning
MEP may ultimately be one of the strongest package markets because both new construction and retrofit need high-performance low-carbon systems. Retaining a concrete frame does not mean retaining 30-year-old ventilation, cooling, controls, electrical distribution or life-safety infrastructure.
The Friction Layer: What Could Still Stop London's Office Pipeline?
The biggest risk in London's office pipeline is not that developers have stopped designing buildings. It is that the journey between design and construction has become harder.
1. Vacant possession
Planning permission cannot remove tenants. Existing leases, relocations and handover dates can control when physical redevelopment begins.
2. Development finance
A consented £500m or £1bn project still requires capital to progress from demolition into structural construction. Institutional ownership improves resilience but does not itself prove a final investment decision.
3. Occupier commitment
Prime rents and restricted future supply can support speculative development, but a major pre-let can materially change lender, investor and board confidence.
4. Demolition duration
Removing a large City building safely can consume a meaningful part of the programme before any replacement superstructure appears.
5. Archaeology and heritage
The Gracechurch Street cluster demonstrates how central London development must respond to archaeology, historic fabric and sensitive urban interfaces rather than simply maximise buildable footprint.
6. Retrofit uncertainty
Retaining a structure reduces embodied carbon but transfers risk into the condition and capacity of an asset designed decades earlier.
7. Contractor and specialist capacity
If several large City towers move into structural construction during the same period, the bottleneck can move from developer intent to availability of experienced teams across façades, MEP, cranes, logistics, temporary works and specialist engineering.
8. Cost
Ultra-prime offices can justify exceptional construction expenditure, but secondary office schemes may struggle to carry the cost of wholesale redevelopment when deep retrofit provides an alternative route.
Is London Heading for an Office Supply Gap?
The strangest feature of the market is that weak new-start volumes do not necessarily indicate weak occupier demand for the best buildings. If developers continue bringing forward only the most robust projects while older secondary offices become less attractive, London could simultaneously have:
• significant total office vacancy;
• weak demand for obsolete secondary space;
• and restricted availability of genuinely premium, efficient Grade A space.
That is the key distinction between office demand and prime-office demand. London does not need every consented office tower to be viable for the strongest sites to command high rents and attract capital. But that dynamic also makes the construction pipeline more concentrated.
The Real London Office Pipeline
The evidence therefore points towards a different interpretation of the 2027–2030 market from the one suggested by skyline renderings. London has a large office planning pipeline, it has a much smaller office construction pipeline. And inside that construction pipeline are two distinct markets:
Ultra-prime new build — large City and West End developments capable of supporting exceptional construction costs because location, quality and future rental performance justify them.
Deep retrofit — existing commercial buildings where structural retention, carbon reduction and improved building performance can create a more viable route than complete demolition.
The weak middle may prove the most important part of the story. Secondary speculative office projects without exceptional location, committed tenants or a convincing retrofit strategy face a much more difficult route to construction. That means the London office market is not disappearing, it is concentrating. For contractors, consultants and suppliers, the advantage will come from identifying which side of that divide each development sits on before committing estimating and delivery resources.
Ten Office Projects and Trends Contractors Should Watch
1. One London / 1 Undershaft — enormous structural opportunity, but demolition and commercial conditions still separate today's site activity from the new tower.
2. 99 Bishopsgate — one of the clearest examples of why a demolition programme and replacement-building start must be recorded separately.
3. 55 Bishopsgate — strategically important because it tests how quickly a major consented speculative tower can convert into committed construction.
4. One Silk Street — watch vacant possession and procurement rather than the planning permission alone.
5. 70 Gracechurch Street — an important hybrid case where retention, occupation and redevelopment combine.
6. 50 Baker Street — illustrates the stronger delivery confidence available on some smaller West End commercial schemes compared with mega-towers.
7. 10 New Bridge Street — a major signal of the retained-frame office market and the specialist work that follows.
8. 1 Embankment Place — potentially one of the clearest examples of large-scale London office renewal through retention rather than demolition.
9. 8 Canada Square — could become a defining example of Canary Wharf's shift from single-occupier office towers towards major repositioning and mixed use.
10. The retrofit share itself — perhaps more important than any single project. If refurbishment continues taking the majority of new-start volume, contractor capability in existing structures becomes a central competitive advantage.
The full contractor implications, sequencing risks and mitigation strategies are included in today’s London Construction Magazine briefing.
Evidence-Based Summary
Research into London's office pipeline indicates that the volume of consented and proposed development substantially exceeds the number of projects with a clear path to substantive construction between 2027 and 2030. The strongest near-term project count sits around 2027, while 2028 could become the more significant year by construction value and structural scale if major City schemes including One London and 99 Bishopsgate complete their pre-construction and demolition stages. At the same time, deep retrofit is becoming a core commercial-construction market, with retained structures shifting expenditure towards investigation, strengthening, temporary works, façades and complete building-services renewal. London's future office market therefore appears increasingly concentrated around ultra-prime new build and technically complex retrofit rather than broad speculative development.
Source Context & Editorial Note
This analysis reflects project and market information reviewed up to 13 August 2026. The research compared planning status, current site activity, vacant possession, demolition, contractor appointments, occupier commitments and stated construction programmes across a broad selection of major London office developments and retrofits. Particular care has been taken to distinguish demolition and enabling works from construction of replacement buildings. A scheme already materially under construction before 2027 has not been treated as a new 2027 start merely because its programme or completion extends into the 2027–2030 period.
Where research sources disagreed on commencement dates, contractor status, project values, pre-lets or programme sequencing, the article avoids converting uncertain information into confirmed fact. Precise delivery years should therefore be read as current construction-intelligence windows rather than guaranteed mobilisation dates. The research also distinguishes office construction value from wider development value and does not treat institutional ownership, planning approval or marketing activity as evidence that full development finance has necessarily been committed.
| Expert Verification & Authorship: Mihai Chelmus Founder, London Construction Magazine | Construction Testing & Investigation Specialist |
