Structural alterations are one of the most effective ways to transform a London home — opening up space, improving light flow, and modernising older layouts. With so many Victorian, Edwardian and 1930s properties across North and North-West London, structural changes are often essential to achieve the open-plan designs families want today.
From removing internal walls to installing new steel beams, these works must be carried out safely, professionally, and in full compliance with Building Regulations.
Below is a clear and practical guide for homeowners planning structural alterations.
What Counts as a Structural Alteration?
Structural works typically include:
Removing internal load-bearing walls
Installing RSJ / steel beams
Chimney breast removal
Creating larger openings for doors, windows or extensions
Strengthening floors and ceilings
Structural support for loft conversions
Replacing or reinforcing old timber joists
Lowering floors / underpinning (if required)
Anything that affects the structure, stability, or load distribution of your home must be designed and approved by a qualified structural engineer.
Do You Need a Structural Engineer?
Yes — always.
A structural engineer is responsible for:
Calculating steel beam sizes (RSJs / UC / UB)
Checking load paths
Designing pad foundations (if required)
Providing structural drawings for Building Control
Ensuring compliance with regulations
Their drawings form the foundation for accurate pricing and safe construction.
Do You Need Building Control Approval?
Absolutely.
All structural alterations require either:
Full Plans Approval, or
Building Notice
A Building Control Officer inspects key stages such as:
Beam installation
Padstones and bearing
Fire protection
Final completion
A completion certificate protects you when selling the property.
Typical Structural Alteration Costs in London
Costs vary depending on access, steel size, and existing structure. On average:
Internal load-bearing wall removal: £1,800 – £4,500
Steel beam installation (RSJ): £1,200 – £3,000
Chimney breast removal: £2,000 – £5,000
Open-plan kitchen structural works: £4,000 – £10,000
Chimney stack support (gallows brackets or steel): £1,200 – £2,800
Prices depend on property type (Victorian terrace, semi, detached, flat), access, waste removal, and finishing work.
How Long Do Structural Works Take?
Small wall removal: 1–2 days
Larger RSJ installation: 2–4 days
Chimney breast removal: 3–7 days
Open-plan structural alterations: 1–2 weeks
Finishing work (plastering, flooring, painting) may extend the total timescale.
Common Mistakes Homeowners Should Avoid
Starting work without structural drawings
Using builders who are not experienced with steelwork
Not notifying Building Control
Choosing the cheapest option based on incomplete plans
Forgetting about fire safety (boarding & insulation)
Not considering temporary support correctly
Structural mistakes are expensive to fix — professional planning prevents problems.
Structural Alterations Across North & North-West London
Areas such as Finchley, Hampstead, Camden, Mill Hill, Barnet, Golders Green, Muswell Hill, Crouch End, Highgate, Edgware, Southgate, and St John’s Wood have properties ideally suited for open-plan conversions.
Older layouts often include:
Narrow kitchens
Multiple small reception rooms
Thick internal walls
Redundant chimney breasts
Structural alteration is the fastest way to modernise these homes.
Why Homeowners Choose Optima Builders for Structural Works
Over 20 years of experience with structural steelwork and internal alterations
Full project management — from drawings to completion certificate
Experienced team familiar with Building Control requirements
Accurate temporary supports and safe installation
Clean, tidy work and respect for your home
Transparent pricing
Whether you need a simple wall removal or a full open-plan transformation, we deliver structural alterations with precision and safety.
Get Expert Advice for Your Structural Project
Thinking about removing a wall or opening up your home?
Share your plans and we’ll provide a free consultation, including guidance on:
structural feasibility
engineering requirements
timelines
cost estimate
Contact us today to discuss your structural alteration project in North & North-West London.
