Expert House Extension Builders Cork

#1 Cork's Trusted House Extension Experts!

We provide expert home extension services throughout Cork with over 20 years of experience transforming local properties. Our proven expertise delivers exceptional results on time and budget, whereas our commitment to safety guarantees tranquility during construction.

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Why Choose Keystone Roofing for Your Home Extension

With 20 years serving Cork, Keystone Roofing Ltd. delivers house extensions that add lasting value and functional space to your property. From single-room additions to full two-storey builds, our certified team manages every detail – planning permissions, council submissions, construction, and finishing. Every extension is backed by our 20-year unlimited warranty and 365-day emergency support.

Our Extension Build Process

Keystone Roofing Ltd. begins with a comprehensive on-site consultation to understand your space requirements and budget. Our experienced team manages every stage – from initial surveys and planning submissions to construction and final inspections – backed by our 20-year unlimited warranty and transparent project management.

Free On-Site Consultation & Site Survey

Our thorough consultation examines your existing property layout, structural requirements, and available expansion space. Using advanced surveying equipment, we identify potential challenges like underground services, boundary restrictions, or foundation needs. We document findings with detailed site plans and photographs, checking property boundaries, existing utilities, access routes, and soil conditions.

Every extension project is unique, so we develop customized design plans based on your functional requirements and aesthetic preferences. With our 20-year unlimited warranty and decades of Cork experience, you’ll receive accurate feasibility assessments and realistic budget estimates. Call 087 223 4228 to schedule your free consultation.

Full-Service Build Management

Keystone Roofing Ltd. brings 20+ years of Cork experience to every extension project. We manage all stages from foundation excavation to final finishes using certified tradespeople and quality materials. Our process includes securing necessary planning permissions from Cork City/County Council (if required), protecting your existing property during construction, building foundations to current Building Regulations, constructing structural walls and roof systems, installing all electrical and plumbing services, and completing interior finishes to your specifications.

Each stage follows strict quality protocols and HSA safety standards. Our registered, insured team guarantees work with a 20-year unlimited warranty and 365-day emergency assistance. Transparent pricing means no hidden fees throughout construction. Call 087 223 4228 for professional house extension services.

20-Year Warranty & Building Regulations Compliance

Every house extension undergoes rigorous inspection at multiple stages. We verify all structural work complies with Building Regulations 2024, document each construction phase with photographs and written reports for complete transparency, and conduct post-completion inspections to ensure weatherproofing and finish quality.

Our standards exceed national building codes and Cork City/County Council requirements. Cork clients consistently receive durable, code-compliant extensions that add long-term property value. With continuous training and professional development, our team delivers precision construction backed by our 365 Emergency Assist Service, 10-year home security warranty, and 20-year unlimited structural warranty.

Our standards exceed national regulations and local building codes. Cork clients consistently receive reliable, lasting results. With advanced equipment and continuous professional training, our team delivers precision repairs backed by our 365 Emergency Assist Service, 10-year home security warranty, and 20-year unlimited warranty.

When to Consider a Home Extension

Growing families and changing lifestyles often outpace existing home layouts. At Keystone Roofing Ltd., we recommend assessing your space needs when life transitions occur. Our 20-year unlimited warranty ensures your extended space serves your family for decades.

You should consider house extensions when your family is expanding and existing bedrooms no longer accommodate everyone comfortably, you’re working from home and need dedicated office space separate from living areas, or aging parents need ground-floor accommodation (granny flat) with accessible facilities. Our team uses modern surveying equipment to assess structural feasibility and space optimization. We respond rapidly with our 365 Emergency Assist Service for urgent project timelines. Call 087 223 4228 to arrange your professional property assessment.

What to Expect During Construction

At Keystone Roofing Ltd., project safety and property protection come first. We use strict HSA safety protocols and professional-grade equipment to safeguard your existing home and our workers during every construction stage.

Safety barriers and clear signage alert family members and visitors to active work zones. Personal protective equipment and certified scaffolding systems protect our team throughout the build. Weatherproofing measures include temporary covers and sealing to protect your existing property during construction. Dedicated project managers provide weekly progress updates and are available for site visits. Our insured professionals follow Building Regulations 2024 standards, arriving on schedule with proper identification and branded uniforms. Our 10-year home security promise and 20-year unlimited warranty guarantee your peace of mind throughout the 10-16 week typical construction period..

What Cork Homeowners Say About Us

Don’t just take our word for it. Read what Cork homeowners say about our roofing services. From emergency repairs to complete roof replacements, we’re proud of the trust we’ve built across Cork City, Douglas, Ballincollig, and surrounding areas.

Slate Roof Repair - Douglas, Cork

Keystone Roofing Ltd handled a slate roof repair and new lead flashing on our terraced house in Douglas, Cork. They explained the issue clearly, fixed a persistent leak, and left the place tidy. Highly Recomended!

Amelia Nolan

Complete Roof Replacement

The team did an immaculate job doing a whole new roof. Very easy to communicate, friendly, professional and hard working. Definitely would recommend. Thanks for a job well done!

Konstantin Hochhaus

Emergency Leak Repair

Keystone Roofing repaired a leak in my roof recently Michael called to inspect the damage and the crew arrived the next morning They did a fantastic job and Im extremely happy with the result A great company to deal with and I would highly recommend them Thanks Michael and crew E Hayes

Esther Hayes

Large Roofing Project Completed On Time

Work carried out to a high standard, here when they said they would be, worked until darkness somedays. Bigger job than expected, worked up until Christmas Eve to make sure work was completed.

Adrian Hickey

Professional Service & Great Customer Care

I am very happy with the work completed by Michael and the lads at Keystone. The team were professional, had great customer service, were honest and overall great to deal with. I would definitely hire them again.

Michelle hurley

Christmas Eve Emergency Repair

Called keystone on Christmas Eve to repair my roof guys had it fixed in a hour at fair price happy to recommend

K Ka

Common Questions About Home Extensions

Do I Need Planning Permission for a Home Extension in Cork?

Not always. Extensions under 40m² may qualify for exempted development. We'll advise and manage any necessary planning applications."

How Long Does the Process Take?

Most home extensions take 10–16 weeks, depending on size, design, and site conditions.

Can You Match the Design to My Existing Home?

Yes. Our architects and builders ensure seamless integration with your current structure and finishes.

Do You Handle the Entire Process, Including Planning Applications?

Absolutely. We provide a complete design-and-build service, including planning submissions.

What Is the Average Cost per Square Metre?

Home extension costs typically range from €1,800 to €2,500 per square metre. Get in touch for an exact quote tailored to your project.

Ready to Add Space to Your Cork Home? Get Your Free Quote Today

Running out of room but can’t face moving? Look, we get it – the market’s insane and you actually like your street. We’ll handle the planning stuff, build you the space you need, and get it done without turning your life upside down for months.