Single-Storey Rear Extensions
The most popular extension type in Cork. Full project management from planning to final clean — foundations, blockwork, roof, glazing and internal finishes included.
Our Extensions Service
Extensions Built to Last — and Built to Live In
A house extension is one of the most rewarding investments a Cork homeowner can make. Done right, it transforms how a family uses their home — more kitchen space, a proper utility room, an extra bedroom, or a light-filled living area connecting the house to the garden.
Timothy Bowen Building & Maintenance has been building house extensions across Cork since 2013. Every extension we build is personally managed by Timothy — from planning compliance and foundation to roof, windows and final finishes. One point of contact. One consistent standard.
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Scope of Work
What's Included
Every extension project is different. Here's the full range of work we carry out — all coordinated by Timothy, all finished to a consistent standard.
Two-Storey Extensions
Add significant floor area in a single build. We manage the full structural design coordination, steelwork, and all trades for two-storey additions to existing homes.
Side Return Extensions
Maximise the underused side passage of your home. Side return extensions add valuable kitchen or dining space and are a popular choice in Cork city terraced properties.
Structural Steelwork & Beams
Large open spans require steel beams properly sized and installed. We coordinate structural engineering sign-off and carry out all steel installation in-house.
Roof, Glazing & Insulation
Pitched, flat or lantern roofs — all insulated to current Part L standards. Bi-fold doors, roof glazing, and high-performance windows sourced and fitted by our team.
Internal Fit-Out & Finishes
Plastering, tiling, flooring, joinery and painting — all internal trades managed by Timothy. We hand over a completed, liveable space, not a bare shell.
Our Signature Speciality
What Others Won't Do — We Will
Wall knock-throughs between the existing house and the new extension
The wall knock-through is the most technically demanding part of any house extension — and it's the part most Cork builders quietly avoid. Opening up an existing structural wall to connect your house to a new extension requires real experience, the right machinery, and senior tradesmen who understand load paths, temporary support, and structural sign-off. It's not something you learn on the job.
13+
Years Doing This
100+
Extensions Built
0
Jobs Walked Away From
Why Most Builders Won't Touch It
Wall knock-throughs on load-bearing walls require temporary support structures, steel beam installation, and precise removal of masonry — all while the existing house stays occupied and structurally sound. Many contractors don't have the experience or the skilled labour to do this safely, so they avoid it or subcontract to someone they've never worked with. The result is delays, liability problems, and finishes that don't match.
Senior Tradesmen Who've Done This Their Whole Careers
Our team has been carrying out wall knock-throughs on Cork homes for over a decade. We know how to read a structure, install temporary propping, place the steel correctly, and achieve a finish that flows naturally from the original house into the new extension. It's part of every extension we build — not an afterthought, and not something we farm out.
Structural Sign-Off Included
Every wall knock-through we carry out is coordinated with structural engineering assessment where required. You get a project that is certifiable, compliant, and properly documented — not just a gap in a wall with a beam pushed in above it.
The Finish Matters Too
The knock-through isn't done when the steel is in. The plasterwork, lintel detailing, floor level transitions and ceiling tie-ins all need to be right. We carry all of this through ourselves — the same team that built the extension finishes the connection. It shows.
Why Choose Us
Trusted by Cork Homeowners Since 2013
We've built our reputation one extension at a time. Here's what makes working with Timothy Bowen different from any other Cork building contractor.
Detailed Written Quote Upfront
No vague estimates. You'll know exactly what your extension costs before we lift a single block. If scope changes, you hear about it immediately — never after the fact.
Timothy On Site, Not a Foreman
You won't deal with a site manager who doesn't know your brief. Timothy oversees every stage himself — particularly the critical wall knock-through and structural phases.
Clean Site, Minimal Disruption
We respect that you live in the house while we work. Site is kept tidy, noise managed to reasonable hours, and access agreed with you in advance — every single day.
Start Date & Completion Date You Can Rely On
We commit to a programme before work starts and we stick to it. Extensions don't drag on for a year with us — we plan, resource, and deliver properly.
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We'll get back to you within 24 hours to arrange a free site visit.
The Process
How It Works
Three straightforward steps from first contact to a finished extension you'll use every day. No hassle, no surprises.
Get in Touch
Fill in the quote form or call us directly. Tell us about the extension you have in mind — the type, the location in Cork, and your rough timescale. We'll get back to you within one working day.
Get a Free QuoteSite Visit & Detailed Quote
Timothy visits your home, takes a proper look at the site, and puts together a detailed written quote. You'll know exactly what you're getting and what it costs — before any work begins.
Get a Free QuoteWe Build & Hand Over
Work starts on the agreed date. Timothy manages every trade — including the structural knock-through — and doesn't sign off until the extension meets the standard his name stands behind.
Get a Free QuoteGoogle Reviews
What Cork Homeowners Say
Real feedback from real clients across Cork who've had extensions built by our team.
Google Review
"Timothy built a large rear extension on our house in Douglas and the knock-through into the existing kitchen was flawless. We'd been told by two other builders they wouldn't do the wall. Timothy's team did it perfectly, on time and exactly on budget."
Rear Extension & Wall Knock-Through — Douglas, Cork
Google Review
"From the initial site visit to handing over the keys, Timothy was professional throughout. Our two-storey extension was a big project and he managed every trade seamlessly. The finish is excellent and the steel beam work is immaculate."
Two-Storey Extension — Carrigaline, Cork
Google Review
"Had a side return extension built in Ballincollig. Timothy was the only builder who walked the site and immediately understood what the knock-through would involve. No hesitation, no hidden costs, brilliant result. Would not use anyone else."
Side Return Extension — Ballincollig, Cork