We specialise in
Understand the full building process, from design and planning permission to construction and handover. At O'Callaghan Construction, we know that building or renovating your home can feel overwhelming. That's why we pride ourselves on being approachable, clear, and supportive throughout the whole process. Whether you're planning a new build, an extension, or just a few small changes, we're here to help. This guide will walk you through how building works - from your first idea to getting the keys in your hand.
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Organising building work can feel overwhelming. That's why we've created this clear and helpful guide to walk you through each stage of a typical building project, whether you're planning a new build, an extension, a renovation, or smaller alterations.
You'll learn who you need to involve, what to expect at each step, and how the building process works from start to finish. Whether you're building from scratch or updating your current home, this guide is here to help you understand what's needed and when. If you'd like a second opinion or some friendly building advice, we're here to help.
The first stage of any building project is to develop a clear design. This typically means working with an architect to create detailed drawings and plans that reflect how you want the finished home to look and function. For simpler jobs, such as internal alterations, a structural engineer may be enough to produce what's needed.
For new builds, a full design is essential before anything can proceed. Renovations and extensions almost always require proper drawings too, especially if there are structural changes or if planning permission is involved. Minor alterations, on the other hand, often don't need formal drawings - sometimes a brief chat and a rough layout is enough to move forward, depending on the scale of the work.
Planning permission is a key step for most new builds and many types of renovations or extensions. You'll usually need an architect or engineer to prepare the drawings and submit the application, although some clients choose to apply themselves with professional guidance.
For new homes, planning permission is almost always required before building can begin. The same applies to many larger extensions or changes to the outside of your home. Smaller alterations inside the home, however, often don't need formal planning approval - but it's always best to check, especially if you're unsure or your property is in a sensitive area.
Once the design is agreed and planning permission is in place, construction drawings are prepared to guide the build. These are detailed technical plans that cover structural elements, electrical layouts, plumbing systems, door and window types, and other key specifications. They allow the builder to price the project accurately and carry out the work as intended.
Construction drawings are essential for new builds and almost always required for larger renovations or extensions. For smaller internal alterations, they're not usually needed unless structural changes are involved. In those cases, a simplified approach may be enough, but we always recommend discussing this early so the right level of detail is in place.
Once the design and drawings are in place, the next step is to work out the cost of the build. A main contractor / primary builder, such as ourselves, can provide an approximate estimate based on your plans, which gives a helpful starting point for budgeting. For larger or more complex projects, a Quantity Surveyor can prepare a more detailed, line-by-line quote that accounts for finishes, fittings, and market prices at the time.
Costing is an essential part of any project, whether it's a full new build, a renovation, an extension, or even smaller alterations. Having a clear sense of the expected costs helps avoid surprises later and gives you confidence in making decisions about materials and specifications.
Once you have your plans and budget in place, the next step is the exciting bit, when building commences.
It's not only builders involved though, there can be a lot of different trades required - electricians, plumbers, carpenters, roofers and more. Building often involve bringing in other specialist companies too, from specialist groundworks firms to mechanical ventilation systems to solar panels, a building project will often involve a wide array of specialist firms. Each brings their own specialism and expertise to the project.
Ourselves we work as Main Contractor (sometimes also called a Primary Builder), which means we look after all this side. We take over from the design team and manage the entire construction process through until handing over the keys. Our role is both building and project management, where we bring in the right specialists to complement our own building team from the large network we've built up over many years in construction.
We also handle all the day-to-day site management, ensuring everything runs smoothly and on schedule. This includes coordinating trades, managing deliveries, and keeping you informed about progress. We pride ourselves on clear communication and a collaborative approach, so you're always in the loop without having to manage every detail yourself.
Congratulations! You've successfully navigated the building process, you have the keys in your hand, and your new home is complete. This is the moment you've been waiting for, and we hope you're thrilled with the results.
Don't worry though if there's little snags or bits to tidy up - this is all part of the process and we'll be here to help you with any final touches. In building it is common for the final payment to not be due until the "snag list" has been completed - for example if there's a door that's sticking a little or a draw that's not running smoothly, this is the time to address those little issues before the project is fully complete.
Whether you are building a new home, extending your current one, or making alterations, bringing the right builder on board makes all the difference. We're here to manage the process clearly and professionally, from the first day on site right through to handover. In the case of a new build, right up to handing you the keys to your new home!
There are three main ways in Ireland to put together your design & build team:
This is the most common approach, where you have two main parties to work with.
The first party is an Architect / Engineer, who looks after the design and planning permission phase. Some projects will need both, but if your architect doesn't offer in-house engineer services, most architects will have good engineers they work with and can recommend, or we can recommend some for you as well. The Architect / Engineer should take your project from initial concept through to planning permission in place, detailed drawings done, ready for that first shovel to start.
The second party is a main contractor, such as ourselves. A main contractor (sometimes called a primary builder) then runs the full construction process, coordinating all trades, handling day-to-day site progress, and keeping everything on track through to handover. It's a smooth, well-managed way to build that keeps you informed without having to manage the entire process yourself. It means your have the full range of options for your design, and you can choose the architect or engineer that best suits your needs. We work with a wide range of architects and engineers, so if you need help finding the right one, we can help with recomendations for that too.
This is what we offer - that Main Contractor / Primary Builder service, looking after everything after the design phase through to full completion.
Some homeowners choose to work with a full-service building company, where everything; architecture, engineering, and construction is all done in-house. This can be a great option for those who want a streamlined process and a single point of contact for everything. However, for some it can be more limiting as you don't have the freedom to pick your own design team, so it's important to ensure that the company you choose has a good reputation and experience in the type of project you're planning.
The final option is to self-manage the build. This means taking on the role of project manager yourself, sourcing each professional, scheduling the work, and overseeing the budget. While it offers a level of control that may suit some people, it also involves a significant amount of time and responsibility. It's a full-time job with the potential to be overwhelming, so do put a lot of thought into this option before deciding if it's right for you.
When planning a building project, you'll often work with both an architect and a structural engineer but their roles are quite different. An architect focuses on the design, layout, and overall vision of your home, turning your ideas into detailed drawings that balance form and function. A structural engineer steps in to make sure that design can actually be built. They handle the technical details like foundations, supports, steel beams, structural safety, along with details like electrical socket placements. For new builds or major renovations, the two often work side by side to bring your project to life safely and efficiently.
You work with your architect/engineer for the design and planning (Do I need an architect?). Then we take over - handling all construction, trades, and project management right through to handing you the keys.