Stevenage Extensions — Local Hertfordshire Builders
Hand-built extensions for Stevenage, Hertfordshire — no sales calls, just a proper on-site quote.
Stevenage Extensions — Local Hertfordshire Builders
Stevenage sits roughly 19 miles from our Bidwell base in Dunstable, so when SG1 homeowners ring about extensions we're rarely far away.
Stevenage combines a designated New Town built from the late 1940s with a much older High Street in the Old Town — two very different building stocks needing very different approaches.
Stevenage extensions for us range across the patch — single-storey rear on New Town estate housing, full matched-brick extensions in the Old Town, and substantial wrap-arounds on the larger detached plots.
Typical Stevenage use cases
- Garden-room style glazed extensions with structural steel
- Single-storey rear kitchen-diners on 1930s semis
- Double-storey side returns on Victorian terraces
- Wrap-around extensions opening up the rear of the house
Stevenage-specific things we plan around
Stevenage New Town districts like Bedwell, Pin Green, Chells and Symonds Green are predominantly 1950s–1970s; the Old Town and surrounding areas have substantial Georgian, Victorian and inter-war stock. Chalky boulder clay dominates Stevenage's geology, but extensive 20th-century earthworks across the New Town mean made-ground is common — we always test before structural work.
- Conservation Area consent on visible Old Town extensions
- Trial pits to confirm what's actually beneath New Town slabs and footings
- Matched brick and tile so the extension reads as part of the original house
Stevenage Borough Council protect the Old Town High Street Conservation Area carefully, and several New Town estates carry restrictive covenants on front elevations.
Materials and methods we use
What's included on Stevenage extensions jobs
- Single-storey rear and side extensions
- Double-storey and wrap-around extensions
- Kitchen, dining and family-room extensions
- Foundations, structural steel and load-bearing alterations
- Matched external brick, tile and rainwater detailing
- Full first and second fix, plaster and joinery
Our extensions process for Stevenage
- 01Site survey
We meet you on site, look at the actual property and talk through what's realistic before drawings or planning go anywhere.
- 02Planning and Building Regs
We work alongside your architect on planning, Building Regs and party-wall awards — or recommend a trusted one.
- 03Foundations and shell
Trial pits, proper foundation depth, accurate setting out and a watertight shell before first fix begins.
- 04First and second fix
Electrics, plumbing, plaster and joinery brought through to a high finish — including matched external brick, tile and rainwater detailing.
- 05Sign-off and handover
Building Control sign-off, our own written guarantee, snagging cleared and a tidy site at handover.
What Stevenage homeowners usually want to know
- Are 1960s Stevenage foundations strong enough for an extension?
- Sometimes — they need verifying. We trial-pit and either bridge or replace rather than rely on a footing that doesn't suit modern loadings.
- Can you work in the Stevenage Old Town Conservation Area?
- Yes — matched brick, lime pointing and traditional roof and joinery detailing are all part of our normal Old Town work.
- Do you cover Knebworth from Stevenage?
- Yes, Knebworth and the surrounding villages sit in our coverage along with the main Stevenage districts.
- Will my Stevenage extension match the existing property?
- Matching brick, tile, rainwater detailing and pointing is part of what we do — particularly important on older Hertfordshire stock around SG1.
- How disruptive is an extension build in Stevenage?
- We keep the existing property habitable wherever possible — clean site, dust sheets, daily tidy-down and clear comms about which weeks affect which rooms.
Where in Stevenage we work
Stevenage work for us splits between rear extensions and modern garden rooms on New Town estate housing and matched-brick period extensions and re-pointing in the Old Town.
- Old Town
- Bedwell
- Pin Green
- Chells
- Symonds Green
- Knebworth edge
Working postcodes: SG1, SG2 · roughly 19 miles from our Bidwell yard.
“Our rear extension is honestly the best part of the house. Done on time, no surprises.”
Extensions elsewhere in Hertfordshire and beyond
Other services we offer in Stevenage
Summary — extensions in Stevenage
Planning a Stevenage extension? Send us the plans and we'll come and price it.
Thinking about extensions in Stevenage? Send a few photos and we'll come out and price it properly.
For more about how we work, see our main extensions page or browse all areas we cover.
Related extensions projects near Stevenage
Recent extensions builds we've completed across Bedfordshire — the same team and standards you'll get in Stevenage.
- Front Porch with Vaulted Lean-To RoofA new front porch and vaulted lean-to roof adding kerb appeal and 4 sq m of practical hallway space.
- Open-Plan Summer Room ExtensionAn additional open-plan summer room built for entertaining, designed to feel bright and connected to the garden all year round.
- Garage Extension — Music RoomExtension of the garage to create a separate room away from the house, purpose-built for music practice.