Find an Extension Builder in Welwyn Garden City

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Extension Builders in Welwyn Garden City

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  • 1-20 of 7,315 extension builders

    We are a reliable Hertford-based building and property maintenance company providing high-quality home improvements, repairs and refurbishment services throughout Hertfordshire and surrounding areas. With strong experience working on residential and...

    Latest Staircases - Wooden Review

    "Very quick service. The supplier usually used was shut for Xmas so I got my own rail from Amazon and Harvey fitted it Xmas eve"

    Reviewed by on
    Based in SG14 2FF, Hertford
    Extension Builder covering Welwyn Garden City
    Member since Nov 2025
    ID Checked

    Kings Maintenance • Over 20 year’s experience • Brickwork and Heritage repairs • Ground works • Internal and External repairs and Construction • Kitchen instillations • Office fit outs • Skyvac gutter cleaning • Free quotations and advise

    Latest Structural Steelwork Review

    "This was only a small job but having already been let down by two other tradespeople dealing with Adam was a breath of fresh air. Understood what I wanted immediately and provided a quick, detailed quote. He followed this up by co..."

    Reviewed by on
    Based in AL7 3XF, Welwyn Garden City
    Extension Builder covering Welwyn Garden City
    Member since Dec 2024
    Public liability insurance

    Small building contractor, patios, driveways, landscaping, garage and shed bases, painting and decorating. Based in Herts. Fully insured.

    Latest Concrete Base Review

    "Polite, respectful, experienced and skilful. Great tradespeople who I will use in the future for many varied tasks and projects."

    Reviewed by on
    Based in AL1 5ST, Saint Albans
    Extension Builder covering Welwyn Garden City
    Member since Jul 2025
    ID Checked

    20 years ago we started a handyman service in and around Welwyn Garden City , this grew into setting up a building company as the work and size of the jobs grew with all the happy customers LOCAL BUILDER 15 YEARS QUALITY WORK WITH LOTS OF RECOMENDA...

    Based in AL7 3UW, Welwyn Garden City
    Extension Builder covering Welwyn Garden City
    Member since Jul 2023
    ID Checked

    Builder 33 years woorked on highways all sorts of trades in the building trade

    Based in AL7 3QS, Welwyn Garden City
    Extension Builder covering Welwyn Garden City
    Member since Jan 2026

    Hi, I am a self-employed builder with 25 years of experience in the building trade. I am reliable, professional, and take pride in delivering high-quality workmanship on every project. Fully insured with public liability coverage, I hold multiple qua...

    Based in AL7 3SY, Welwyn Garden City
    Extension Builder covering Welwyn Garden City
    Member since Nov 2025

    Hi, we are a building, electrical and refurbishment company in wgc, we carry out garage conversions to re-wires and everything in between, all trades covered, fully insured , niceic and gas safe certificates issued, we also work in the commercial se...

    Based in AL7 3UW, Welwyn Garden City
    Extension Builder covering Welwyn Garden City
    Member since Jan 2023
    ID Checked

    Williams Construction & Build Limited is a trusted, family-run business that stands out for its commitment to reliability, honesty, and exceptional customer service. We believe in going the extra mile to ensure every project is completed to the h...

    Based in AL7 4DF, Welwyn Garden City
    Extension Builder covering Welwyn Garden City
    Member since Dec 2024
    ID Checked

    Hello everyone We are a team based in Welwyn Garden City focused on building extended lofts and full refurbishments. We already have several buildings around that can be seen and get the opinion of our former clients on how we work and what our atti...

    Based in AL7 4DJ, Welwyn Garden City
    Extension Builder covering Welwyn Garden City
    Member since Apr 2025
    ID Checked

    Ws home improvements Small repairs to major renovations All types of work interior to exterior Over 25 years experience

    Based in AL7 3JQ, Welwyn Garden City
    Extension Builder covering Welwyn Garden City
    Member since Mar 2025

    We are a small business who have been trading for 5+ years, location Welwyn Garden City. We guarantee that our work is quality and you’ll be left satisfied with the whole process

    Based in AL7 3HB, Welwyn Garden City
    Extension Builder covering Welwyn Garden City
    Member since Oct 2023

    Renoelevation Ltd is dedicated to becoming your contractor of choice no matter the service. We pursue excellence and our dedicated and experienced team drive to deliver quality in a timely fashion. we provide construction services and every job sche...

    Latest Builder Review

    "Mario was great! very helpful and reliable. I recommend him to everyone without any hesitation. 10/10."

    Reviewed by on
    Based in WD5 0LW, Abbots Langley
    Extension Builder covering Welwyn Garden City
    Member since Mar 2021
    ID Checked

    Hi, I’m a bricklayer doing all kind of jobs about bricks and blocks. We are one of the bests on what we are doing. What makes us different of others is that we are big on quality and reasonable on prices, because we want to grow with you. We are sure...

    Latest Groundwork Review

    "Great team, very professional from start to finish. Was offered a quote same day, given a time scale for the job in which they delivered earlier than expected. They also cleaned up very well and would recommend them to everyone."

    Reviewed by on
    Based in HA7 1QX, Stanmore
    Extension Builder covering Welwyn Garden City
    Member since Mar 2023
    ID Checked

    Hi we’re building company with experience of building renovation extensions garage garden gardens house and kitchen dizayn garden houses garage we’re talking cares about your property and you work

    Latest Laminate Flooring Review

    "Hosein and his team did the renovation of my flat. They did an excellent job, no hidden extras and high standard. Highly recommend"

    Reviewed by on
    Based in N11 2QE, London
    Extension Builder covering Welwyn Garden City
    Member since Aug 2018
    Public liability insurance

    We are dedicated Contractors and looking for local work to undertake project management and construction services. We are a family business and dedicate our time and energy to the delivery of high quality work. We undertake individual maintenance wor...

    Latest Builder Review

    "James and his company contributed and delivered a complete refurbishment of our home in North London. He and his team were reliable, cautious in what they were doing, creative with a strong focus on the engineering requirements of..."

    Reviewed by on
    Based in N6 5JT, London
    Extension Builder covering Welwyn Garden City
    Member since Dec 2025
    ID Checked

    Are you looking to transform your indoor/outdoor space??? K&L Build Design and Maintenance is a trusted building and landscaping company committed to delivering exceptional workmanship and reliable service across every project. Specialising in b...

    Latest Chimney Building / Repair Review

    "Good guys, came in time, done the job, no fuss, left no sign behind after the job. Would recommend."

    Reviewed by on
    Based in WD25 9EU, Watford
    Extension Builder covering Welwyn Garden City
    Member since Nov 2025
    ID Checked

    Im A professional builder combines technical skill with strong organization and leadership. You interpret blueprints accurately, coordinate workers and subcontractors, and maintain strict quality standards. You use modern tools and proven methods to...

    Latest Builder Review

    "Highly recommend, work was done to a high standard and met our expectations, very clean and organised."

    Reviewed by on
    Based in HA3 0QH, Wembley
    Extension Builder covering Welwyn Garden City
    Member since Nov 2025
    ID Checked

    NLK Group, based in London, provides bespoke services in carpentry installation, custom-made wardrobes and cabinets, house refurbishments, and various construction projects. Our offerings include: • Kitchen fittings • Fitted wardrobes • Painting...

    Latest Wooden Doors - External Review

    "Naim did a fantastic job with replacing our external doors- front and rear. Communication was great and we are happy with the results."

    Reviewed by on
    Based in WD25 0GD, Watford
    Extension Builder covering Welwyn Garden City
    Member since Nov 2016

    A family business committed to quality, value and client satisfaction in every project. From little kitchen to big extensions

    Latest Garage Conversion Review

    "Great Price , great communication and completed job to high spec , very good team with him"

    Reviewed by on
    Based in HA7 1FP, Stanmore
    Extension Builder covering Welwyn Garden City
    Member since Jan 2020
    ID Checked

    We are a building company that specialise in refurbishment work. Residential or Commercial works. We have been working in the industry for 30 years. We are happy to give you a quote for all types of work, with no obligation.

    Latest Structural Steelwork Review

    "Professional and prompt provision of written job specification and estimate. Good quality work rebuilding and repairing patio retaining wall, completed within agreed time. Would definitely use again."

    Reviewed by on
    Based in HA6 1BG, Northwood
    Extension Builder covering Welwyn Garden City
    Member since May 2025
    ID Checked
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    Our Reviews

    All reviews are submitted by homeowners who have had work completed as part of using our service. Whilst every effort is made to verify and check reviews, we ask all homeowners to conduct their own research and follow our Homeowner Checklist before hiring.

    To understand more about our reviews process, please visit our Reviews Policy.

    Find Extension Builders Near You

    Trusted Extension Builders in other locations

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    Recently posted Extension Builders jobs

    Join over 1,000,000 happy homeowners who have posted their job on MyJobQuote.

    Job posted in Barking

    Media wall and fitted wardrobe

    Job posted in Beckton

    To extend current kitchen extension

    Job posted in Hayes

    Back garden extension 4meters

    Job posted in Sandy

    Plan to have built a small rear single storey extension to rear of house from dining area and abutting to existing kitchen extension (two walls and a...

    Job posted in High Wycombe

    Build two storey extension to the side of the house, garage already in place, will likley need to be demolished to rebuild. Plans drawn, plannign app...

    Job posted in Barking

    Media wall and fitted wardrobe

    Job posted in Beckton

    To extend current kitchen extension

    Job posted in Hayes

    Back garden extension 4meters

    Job posted in Sandy

    Plan to have built a small rear single storey extension to rear of house from dining area and abutting to existing kitchen extension (two walls and a...

    Job posted in High Wycombe

    Build two storey extension to the side of the house, garage already in place, will likley need to be demolished to rebuild. Plans drawn, plannign app...

    Job posted in Hounslow

    this is to get a quote. Planning permission to be granted

    Job posted in Mill Hill

    there is currently a conservatory in situ and i want to replace this with a proper extension

    Job posted in Wanstead

    Single storey L-shaped wraparound extension to ground floor kitchen to create kitchen diner space. Current kitchen is 7.5m2 and proposed is 22m2

    Job posted in Waltham Cross

    Footings dug and filled, concrete floor and brease block walls built

    Job posted in Luton

    Skimming on one wall as part of wall has been taken off so need builder

    Job posted in Hounslow

    this is to get a quote. Planning permission to be granted

    Job posted in Mill Hill

    there is currently a conservatory in situ and i want to replace this with a proper extension

    Job posted in Wanstead

    Single storey L-shaped wraparound extension to ground floor kitchen to create kitchen diner space. Current kitchen is 7.5m2 and proposed is 22m2

    Job posted in Waltham Cross

    Footings dug and filled, concrete floor and brease block walls built

    Job posted in Luton

    Skimming on one wall as part of wall has been taken off so need builder

    Job posted in Luton

    Looking to Build a double storey rear extension lower 27m squared upper 12m squared . Lower has kitchen upper will be ensuite , drawings done , appova...

    Job posted in Childs Hill

    I’m in a conservation area and can only extend my kitchen that’s 2.5m wide out by 2m so adding a total of 5m^2

    Job posted in Chingford

    Build single storey extension where the kitchen, dining room and additional bathroom will be. Approximately 27sqm

    Job posted in Luton

    Looking to Build a double storey rear extension lower 27m squared upper 12m squared . Lower has kitchen upper will be ensuite , drawings done , appova...

    Job posted in Hornchurch

    a. Extension to enable a disabled child to have a wheelchair accessible bedroom and shower room b. Raising kitchen floor OR relocating kitchen door de...

    Job posted in Luton

    Looking to Build a double storey rear extension lower 27m squared upper 12m squared . Lower has kitchen upper will be ensuite , drawings done , appova...

    Job posted in Childs Hill

    I’m in a conservation area and can only extend my kitchen that’s 2.5m wide out by 2m so adding a total of 5m^2

    Job posted in Chingford

    Build single storey extension where the kitchen, dining room and additional bathroom will be. Approximately 27sqm

    Job posted in Luton

    Looking to Build a double storey rear extension lower 27m squared upper 12m squared . Lower has kitchen upper will be ensuite , drawings done , appova...

    Job posted in Hornchurch

    a. Extension to enable a disabled child to have a wheelchair accessible bedroom and shower room b. Raising kitchen floor OR relocating kitchen door de...

    Job posted in Chalfont Saint Giles

    Build a double storey extension at the back of the house, for a kitchen diner, adding one bedroom and moving the bathroom upstairs.

    Job posted in Brentford

    I am looking for quotes to build a 3 x 5 single storey extension to expand my kitchen into. Lean to roof with skylights. Glazing across the 5 mtr span...

    Job posted in Luton

    Rear extension and Annexe in the garden

    Job posted in Balham

    Structural survey of proposed flat roof access. Need survey for building regs. Propose french door to left of windows,. allowing access to flat roof

    Job posted in LONDON

    My house needs doing up good and proper

    Job posted in Chalfont Saint Giles

    Build a double storey extension at the back of the house, for a kitchen diner, adding one bedroom and moving the bathroom upstairs.

    Job posted in Brentford

    I am looking for quotes to build a 3 x 5 single storey extension to expand my kitchen into. Lean to roof with skylights. Glazing across the 5 mtr span...

    Job posted in Luton

    Rear extension and Annexe in the garden

    Job posted in Balham

    Structural survey of proposed flat roof access. Need survey for building regs. Propose french door to left of windows,. allowing access to flat roof

    Job posted in LONDON

    My house needs doing up good and proper

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