House Extensions
Single storey, double storey, rear and wrap-around extensions across Bolton.
Learn more →KJL Builders are local, fully insured builders covering Bolton and the surrounding areas — house extensions, knock throughs, garage conversions, porches, bricklaying, garden walls, kitchen renovations, loft conversions and commercial building work, all professionally managed from first quote to final finish.
Bolton has a wide mix of property styles, from traditional Victorian terraces and stone-built homes to inter-war semis, modern estates and newer developments — and each comes with its own considerations when extending, converting or renovating. Having worked across Bolton and the surrounding areas, we understand the construction challenges that different types of properties can present and what's required to keep projects running smoothly through building control and achieve sign-off from Bolton Council without unnecessary delays.

Complete protection for your property and our team throughout the work.
Experience with Bolton's Victorian terraces, stone-built homes, semis and modern estates.
From Bolton town centre out to Horwich, Westhoughton, Farnworth and beyond.
Clear, fair quotes with no hidden costs before any work begins.
We liaise directly with Bolton Council building control, architects and structural engineers, and can source these professionals for you.
We don't take large payments up front — payments are staged against completed, inspected work.
Every building service we offer, available right across Bolton.
House Extensions
Single storey, double storey, rear and wrap-around extensions across Bolton.
Learn more →Knock Through
Structural wall removal and steel beam installation for open-plan Bolton homes.
Learn more →Garage Conversions
Turn your Bolton garage into an office, bedroom, gym or extra living space.
Learn more →Porches
Open, enclosed and gable-fronted porches that suit Bolton's terraces and semis.
Learn more →Bricklaying Contractors
New brickwork, blockwork, repairs and repointing matched to Bolton's period brick and stone.
Learn more →Garden Walls
Boundary walls, retaining walls and brick garden walls built to last.
Learn more →Commercial Builders
Brickwork, steel installation, dry lining, plastering and painting for Bolton businesses.
Learn more →Kitchen Fitters
Full kitchen renovations and fitted installations for homes across Bolton.
Learn more →Loft Conversions
Dormer, Velux and hip-to-gable loft conversions, loft boarding and loft bedrooms, offices and ensuites for homes across Bolton.
Learn more →We cover every Bolton postcode district — from the town centre out to the surrounding suburbs and towns. Here's a full breakdown of the areas within each postcode.
| Postcode | Areas Covered |
|---|---|
| BL1 | Bolton Town Centre, Smithills, Halliwell, Heaton, Johnson Fold, Astley Bridge, Hall i'th' Wood, Doffcocker |
| BL2 | Ainsworth, Bradley Fold, Bradshaw, Breightmet, Harwood, Tonge Fold, Tonge Moor |
| BL3 | Little Lever, Great Lever, Darcy Lever, Ladybridge, Morris Green, Daubhill, Deane |
| BL4 | Farnworth, Kearsley, Moses Gate |
| BL5 | Over Hulton, Westhoughton |
| BL6 | Blackrod, Horwich, Lostock, Rivington |
| BL7 | Belmont, Bromley Cross, Chapeltown, Edgworth, Egerton, Turton |
Don't see your exact street listed? We cover the whole of Bolton — get in touch and we'll confirm we cover your postcode.
Costs vary by property type and the scale of work — a stone-built terrace in Halliwell or a semi in Bromley Cross will differ from a new-build near the town centre. Here's a rough guide to help with budgeting; we recommend a site visit for an accurate quote.
Porches, garden walls, bricklaying repairs and small garage conversions.
Knock throughs, full garage conversions and single storey extensions.
Double storey extensions, wrap-around extensions and commercial fit-outs.
For an accurate estimate, we recommend requesting a personalised quote based on your Bolton property and project requirements. Get in touch →
As well as every Bolton postcode, we cover the wider Bolton borough and surrounding towns, including:
A clear, structured process to keep your Bolton project on track from start to finish.
We discuss your ideas, goals and budget for your Bolton property.
We visit your property to assess the work and confirm exactly what's needed.
A clear, transparent breakdown of costs, materials, labour and timelines.
We liaise with Bolton Council building control and, where needed, architects and structural engineers.
Our experienced team carries out the work to a high standard, keeping you updated throughout.
We walk through the finished project with you to make sure everything meets your expectations.
Feedback from Bolton homeowners and businesses who chose KJL Builders.
KJL Builders extended our terrace in Halliwell and matched the original stonework perfectly. Professional from the first quote to the final walkthrough.
We had a knock through done on our semi in Horwich — tidy, reliable and the steel beam installation was handled without any fuss.
Converted our garage in Farnworth into a home office. Great communication throughout and finished on schedule.
Useful information before you start planning a building project in Bolton.
Ask us a questionWe cover every Bolton postcode from BL1 to BL7 — including the town centre, Smithills, Halliwell, Heaton, Astley Bridge, Breightmet, Harwood, Little Lever, Great Lever, Deane, Farnworth, Kearsley, Westhoughton, Horwich, Blackrod and Bromley Cross — plus the wider Bolton borough.
Yes. Bolton has a number of conservation areas and listed properties, particularly around the town centre and older suburbs. We're experienced working within these constraints and can advise on what's required before work starts.
Yes, we liaise directly with Bolton Council's building control team and, where required, architects and structural engineers — and can source these professionals for you if you don't already have your own.
Yes, alongside period terraces, stone-built homes and semis across Bolton's suburbs, we also carry out work on properties in and around the town centre, subject to any building management rules that apply.
House extensions, knock throughs and steel beam installation, garage conversions, porches, bricklaying, garden walls, kitchen renovations, loft conversions and commercial building work — all available across every area of Bolton.
Costs vary widely depending on the project and property type, from around £1,500 for smaller jobs to £30,000+ for larger extensions and commercial work. Contact us for a personalised quote based on your property.
We don't take large payments up front. Payments are staged against completed, inspected work, and for structural elements we don't take payment until the building inspector has signed them off.
Tell KJL Builders what you have planned and arrange a free quote anywhere in Bolton.
Fill in the form below with a few details about your Bolton project and we'll get back to you with a free, no-obligation quote.
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