Extensions &
Structural Works
The Service
More space. Properly built.
Extensions and structural alterations are the most technically demanding work we do. They involve new foundations, steelwork, underpinning, waterproofing, and building control compliance — all before a single finish is applied. Done well, they transform how a property works. Done badly, the problems are structural and permanent.
Melner manages the full programme from planning through to completion. We work with your architect or appoint one from our network. We liaise with building control, structural engineers, party wall surveyors, and planning authorities — so you deal with one team, not six.
Whether it's a rear extension to open up a kitchen, a side return to gain a dining room, a loft conversion for a new bedroom, or a full basement dig to double the usable area — we approach every project with the same principle: build the structure to last generations, then finish it to the standard the address demands.
Our structural works are delivered entirely in-house. We don't hand foundations to one subcontractor and steelwork to another. One site manager oversees the entire programme, present daily, accountable for everything.
What we build
Every type of extension and alteration.
Rear Extensions
Single and double-storey rear extensions with full-height glazing, slim-line steel frames, and seamless connections to the garden. Designed to flood the ground floor with natural light.
Side Returns
Infilling the narrow passage alongside Victorian and Edwardian terraces to create open-plan kitchen and dining spaces. Structural steel, glazed rooflights, and integrated drainage.
Basement Conversions
Full basement excavation, underpinning, tanking, and waterproofing. Cavity drain membrane systems with sump and pump for long-term reliability beneath the water table.
Loft Conversions
Dormer, mansard, and hip-to-gable conversions. New staircases, structural floor reinforcement, and full M&E integration. Planning and party wall agreements managed throughout.
Internal Structural Works
Load-bearing wall removals, new steel beam installation, floor reinforcement, and layout reconfiguration. The invisible work that makes the visible design possible.
Garden Rooms
Freestanding garden studios, home offices, and outbuildings — from timber-clad structures with green living roofs to fully insulated year-round workspaces with power and data.
The structure is the one thing you can never redo cheaply. Every beam, every foundation, every connection — it either works for the next hundred years or it doesn't. There is no middle ground.
How we deliver
From planning approval to finished space.
Full scope
Structure through to final finish.
Every extension project is managed end-to-end by Melner. The scope below covers the full range of works we deliver in-house — adapted to the specific requirements of each property and brief.
- Planning applications and liaison
- Party wall agreements
- Building control compliance
- Demolition and site clearance
- Foundations and underpinning
- Structural steelwork
- Basement excavation and tanking
- Brickwork and blockwork
- Roofing and flat roof systems
- Glazing and slim-line frames
- Drainage and groundworks
- Full M&E installation
- Plastering and insulation
- Joinery and fit-out
- Tiling, flooring, and finishes
- Landscaping and external works