Lynwood Grove — Full Renovation Case Study

The brief

A house rebuilt
from the inside out

"When choosing between different companies and quotes, it's never easy to decide who to trust with a project that impacts both your family's lifestyle and a significant financial investment."

The client came to us with an ambitious vision — not a refresh, but a wholesale transformation of their 100-year-old London home. The property needed a first-floor rear extension, but the scope quickly grew to encompass nearly every system in the building.

We were appointed to manage and deliver the entire commission, coordinating structural engineering, building regulations, and all trades in-house throughout the six-phase build — including seamless coordination with specialist subcontractors for air conditioning, MVHR, and solar installation.

Scope of works

First-floor rear extension Full roof replacement External wall insulation Complete electrical rewire Underfloor heating throughout Air conditioning MVHR ventilation New plumbing throughout Solar panel installation Silicone render finish Full replastering Two new ensuite bathrooms Garage conversion to annex Five bespoke fitted wardrobes New flooring throughout Full redecoration

What made this project distinctive

The challenges of a
century-old house

A 100-year-old property presents a fundamentally different set of challenges to a modern build. Behind every wall lies the unknown — unexpected structural conditions, redundant services, substandard previous work, and quirks that no survey fully anticipates.

What distinguishes Fellner Construction's approach is the ability to listen carefully to the client and find practical, well-thought-out solutions as those surprises emerge. Coordination with specialist subcontractors for air conditioning, MVHR, and solar was managed seamlessly throughout — with Fellner taking full responsibility for the final result at every stage.

Many of the best ideas came from open discussions along the way. The project was a genuine collaboration from first consultation to final handover.

Property age Approx. 100 years

Specialist coordination A/C · MVHR · Solar

Approach Full responsibility taken

Fixed price Agreed before works began

Bespoke wardrobes 5 — each unique specification

Result 100% client recommendation

How we built it

Six phases,
one seamless result

Each phase was planned and sequenced to allow every trade to proceed without interfering with what came before or after. Click any item to read the full detail.

Initial consultation to understand the full project scope, practical requirements, preferred layout, and design vision — with particular attention to the challenges of a 100-year-old property and the family's long-term needs.

Detailed survey of the existing property layout, structural elements, and all current services — plumbing, heating, electrical, and drainage — to fully understand what was being worked with and where constraints existed.

Coordination with a structural engineer to review the existing building and determine all required alterations — including steel beam specifications, load-bearing wall assessments, and foundation requirements for the extension.

Full mechanical and electrical design covering underfloor heating zones, MVHR ventilation, air conditioning layout, and integration of the solar panel system — coordinated with specialist subcontractors from the outset.

Assessment of the existing building envelope to identify thermal improvement opportunities, followed by preparation and submission of all Building Regulations documentation. Coordination with building control through the approvals process.

Proposed west elevation

Roof plan

Scaffolding erected to the front and rear for safe access to roof and upper structural areas. Hoarding, dust protection, and floor coverings installed throughout working areas to protect the property.

Careful isolation and disconnection of all electrical, plumbing, and heating services before demolition began. Redundant pipework, wiring, and fittings safely removed.

Careful demolition of the roof structure, internal walls, and chimney breast and stack — carried out to minimise disturbance to the remaining structure. The external wall opening from chimney removal closed with matching brickwork.

New structural openings formed and steel beams installed in accordance with the structural engineer's drawings and calculations — creating the framework for the new extended layout above.

Scaffold erection

Demolition begins

Steel beams installed

New rear extension walls built using appropriate blockwork in accordance with approved drawings — including setting out, wall construction, lintels, and integration with the existing building structure.

Full new roof structure installed across both the existing house and new extension — roof timbers, structural supports, and preparation for coverings in line with structural drawings and building regulations.

Existing garage converted and integrated into the ground-floor bedroom. Structural alterations, insulation upgrades, and seamless connection to the main house layout all completed within this phase.

Internal partitions formed for both new ensuite bathrooms. First-fix plumbing and drainage pipework installed — water supply, waste pipes, and connections routed and positioned ready for second-fix sanitary fittings.

Extension walls

Roof structure

Weatherproofing

Flat roof formation & boarding

New roof coverings installed across the entire house and garage. An integrated solar panel system fitted flush within the roof covering — not mounted above it — for a cleaner appearance and better long-term performance.

Air conditioning system installed in coordination with the specialist subcontractor — internal units, external condenser units, pipework, and electrical connections. MVHR mechanical ventilation with heat recovery installed throughout to provide a balanced indoor climate.

Existing windows and front door removed and replaced with new energy-efficient units throughout. New French doors installed to the ground-floor bedroom providing direct garden access.

Full external wall insulation system installed across all elevations — insulation boards fixed, reinforcing mesh applied, and base coat prepared — significantly improving the building's thermal performance.

Roof covering and solar panel installation

Roof covering & solar panels

Flat roof & ridge tiles

External insulation and Velux installation

External insulation & Velux

Windows installation and silicone render application

Windows & silicone render

Application of the full external render system — base coat, reinforcing mesh, and silicone render finish — over the external wall insulation. A clean, durable, weather-resistant exterior that transformed the appearance of the building.

Insulated sandwich panels installed to receive the underfloor heating pipework. Wet underfloor heating circuits laid throughout, manifolds and zone controls installed, and the system connected to the boiler — providing efficient, consistent heat distribution across every room.

Full tiling of all bathroom and ensuite areas — walls and floors — including surface preparation, waterproofing, tile fixing, grouting, and finishing trims.

New floor finishes installed throughout — timber flooring and tiles where specified — including surface preparation, installation, and all finishing trims.

Plastering & 2nd fix plumbing

Tiling

Five custom-built wardrobes designed and installed across the bedrooms — each with a different specification and layout requirement, all executed to a high standard. The client specifically highlighted these as deserving special mention. Carcasses, internal fittings, lighting, and doors all fitted and adjusted to perfection.

Custom bathroom cabinetry installed in both new ensuite bathrooms — vanity units, storage cabinets, and associated fittings designed to suit each bathroom's layout and the overall design language of the project.

Existing staircase refurbished with wooden overlays fitted to the treads and risers. Recessed LED light strip channels formed into each step, with lighting connected to provide subtle, consistent illumination — one of the most distinctive features of the completed project.

New electrical accessories throughout — sockets, switches, thermostats, and control units. Coving installed at wall-to-ceiling junctions. All surfaces filled, primed, and painted to a meticulous standard. The finished property was handed over with all documentation, warranties, and compliance certificates.