Design, Cost & Planning
Most extensions are drawn first and priced last, which is why so many come back over budget. We price yours as we design it. The figure you agree at the start is the figure you build to.
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100+ Projects Delivered
Across Greater Dublin Region
Here is how most Dublin extensions go over budget. You pay for drawings, the design is finished, then builders price it and the number is too high. Now the design is fixed, so the only way down is to redraw it.
That is two bills. One for a design too expensive to build, one for the changes to fix it. The drawings were fine. Nobody priced them while changing your mind was still cheap.
Rated 5★ across Google, Houzz, and OnlineTradesmen by Dublin homeowners.
"Professional, reliable service with clear communication and integrity."
"Professional, reliable service with clear communication and integrity. The team kept us informed at every stage and delivered exactly what was promised. Would recommend to anyone looking for a trustworthy provider."
Read full review"Excellent communication and budget-friendly suggestions throughout."
"Excellent communication and budget-friendly suggestions throughout. They took the time to understand our needs and offered practical options at every step. The end result exceeded our expectations."
Read full review"Excellent communication and support throughout. Highly recommend."
"Excellent communication and support throughout. Highly recommend. From the first call to the final handover everything was handled professionally. The team was responsive, knowledgeable and clearly cared about the outcome."
Read full review"Outstanding work from start to finish. Couldn't be happier with the result."
"Outstanding work from start to finish. Couldn't be happier with the result. They were punctual, tidy and clearly took pride in their craft. The whole project came in on time and on budget."
Read full review"Genuinely impressed with the quality and attention to detail."
"Genuinely impressed with the quality and attention to detail. Every aspect of the project was carefully considered and the finish is excellent. I'd use them again without hesitation."
Read full review"Top-class service. Friendly team and a fair price."
"Top-class service. Friendly team and a fair price. They were upfront about everything, no hidden surprises and the work was completed to a very high standard. Already recommended them to a neighbour."
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Our cost plan breaks your whole build down element by element, from architectural design to engineering. Our quote is based on real construction rates. We ensure that what you sign is what you pay.
We win the job by leaving things out and then recover the difference through variations once you are committed. The cost plan we make has no place to hide an extra because every element is already on the quote.
BuildTech follows a clear four-step pathway, from initial feasibility through to completed construction, designed to protect your budget and keep your project on track.
A standalone architect draws your project, then hands it to a builder to price. Two parties, two numbers, and they rarely match. At BuildTech, we price your project and build it. Our team draws it, prices it, and builds it, so the cost on the page is the cost on-site.
Our experts handle everything: your drawings, the price, and the build. So, one team is accountable when it matters. If your budget and your ambitions do not line up, you hear it at our feasibility stage, before a design fee is committed.
This stage produces five things, and each one shuts down a specific overrun. Here is what you get, and what it saves you from.
First, we measure your home and draw it exactly as it is. If a design is based on a guessed layout, it goes wrong on site, and fixing it costs you extra. An accurate survey at the start stops those problems before they begin.
We design the layout with your budget in front of us the whole time. If a choice is going to push the cost up, we tell you while it is still easy to change, not after it is built. You end up with a design you like and can afford.
We produce drawings detailed enough for a builder to price accurately and build without guessing. When a drawing leaves detail out, someone has to decide it on site, and that always costs more. Clear drawings keep that money in your pocket.
We build the structural design and building regulations into the drawings from the start, not as an afterthought. We coordinate the structural engineering ourselves, so the design is safe, compliant and ready to build. Every project is certified by an Independent Chartered Engineer on completion.
Finally, we price every part of the build in detail and fix that price. No open tenders, and no vague costs left to be filled in later at a figure you never agreed to.
You can usually spot a budget problem before the build starts, if you know what to look for. Here are four warning signs at the design and quoting stage, and what each one is really telling you.
A single figure with no detail behind it is a starting price, not a final one. Without a line-by-line breakdown, there is nothing stopping it from climbing once work begins.
If someone priced your project before the design was complete, they were guessing. The real number arrives later, usually higher, once the details are actually drawn
A price based on assumptions about your property is a price that will change. Until someone measures what is actually there, any figure is provisional
Applying for full permission when the works are Exempted Development — or vice versa — wastes time & money. We confirm the correct route at feasibility stage.
Our cost and technical design is the stage that turns an idea into something you can actually build, with a price you can trust. Skip it, or rush it, and you are building on guesswork. Here is why it matters before any work starts.
If your project is exempted development, we will confirm that at feasibility. Where permission is required, our planning permission service manages the full application.
A feasibility consultation gives you the honest picture before you commit.
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We review your enquiry before confirming a consultation — ensuring only suitable projects proceed.
What's Included
Related Services
Not sure where to start?
A feasibility consultation (€200 call · €500 home visit) confirms your planning position before you spend anything on drawings.
BuildTech is a specialist design and build contractor. We take on a focused range of projects — and we do not progress any project without a clear, agreed budget.
The most common home project in Dublin. Open-plan kitchen and living, utility room, or additional family space — from feasibility through to a certified, compliant build.
Whole-home renovations and structural alterations for Dublin homeowners. Internal reconfigurations, layout redesign, and full refurbishment — all budget-led from day one.
€200 call or €500 home visit. We establish what is realistically achievable within your budget before any design work begins — saving you time, money, and stress.
Full application management — pre-planning strategy, drawings, submission, and decision monitoring. Many extensions are planning exempt; we confirm this first.
Cost Planning & Construction Review from €2,500 + VAT. We provide a full cost breakdown of your existing drawings — gap identification, budget alignment, and value engineering.
Measured survey, technical layout, and a detailed cost plan — all aligned to your budget before construction begins. No over-specified designs that cannot be built within your means.
Each project below started with a feasibility consultation and a clear budget. Here is what we delivered.
Extension + Renovation
Location : Dublin
Scope : Ground floor knock-through, rear extension, open-plan kitchen and living
Status : Planning exempt
✓ Delivered on time and on budget
Extension + Renovation
Scope : Full home renovation of period seafront property
Status : Planning exempt
✓ Full project management, completed on programme
Extension + Renovation
Location : Dublin 14
Scope : Single-storey rear extension and partial ground-floor renovation
Status : Planning exempt
✓ On budget, handover on schedule
Extension + Renovation
Location : Mount Merrion, South Dublin
Scope : 20 sqm flat-roof rear extension, open-plan kitchen and dining
Status : Planning exempt
✓ Completed on time and on budget
Extension + Renovation
Location : Dublin
Scope : Structural reconfiguration, split-level open-plan kitchen and lounge
Status : Planning exempt
✓ Full project management included
No obligation. No pressure. Just honest advice.