ADVICE
STRAIGHT ANSWERS TO THE QUESTIONS PEOPLE ACTUALLY ASK.
Straight answers to the questions people actually ask me before they buy a site, before they extend, before they spend money they can’t get back.
Most of what goes wrong with a building project goes wrong early, in the decisions people make before they ever ring an architect. These articles are here to help you make those decisions better whether you end up working with me or not.
If your site or your house is anywhere near the border, pay particular attention to anything mentioning both jurisdictions. The rules in Northern Ireland and the Republic are genuinely different, and that difference is the thing that catches most people out.
GOT A SPECIFIC QUESTION ABOUT YOUR OWN PROJECT?
An article can only tell you so much. If you want to know where your site or house actually stands, start with a free Fit Call fifteen minutes to see if we’re a match or go straight to a Project Clarity Review.
RURAL PLANNING
DO YOU NEED PLANNING PERMISSION FOR A HOUSE IN THE COUNTRYSIDE?
Short answer: almost certainly yes, and getting it is the hardest part of the whole project. If you’re planning a one-off house in the countryside anywhere near Derry, Donegal, Tyrone or Limavady, this is the thing that decides whether your project happens at all.
Here’s the part people find hard to hear: owning a field doesn’t mean you can build on it. Rural housing is the most tightly controlled area of planning there is, on both sides of the border, and the rules are strict for a reason, councils are trying to stop the countryside filling up with houses.
Northern Ireland: does your site fit a category?
In the North, houses in the countryside are assessed against the Strategic Planning Policy Statement (SPPS) and the retained countryside policy of PPS21 Sustainable Development in the Countryside, which works through policies numbered CTY1 to CTY16. In the Derry and Strabane district, the Local Development Plan 2032 now carries the strategic countryside policy.
CTY1 is the gateway. It sets out the limited circumstances where a new house in the countryside is acceptable. If your proposal doesn’t fit one of the recognised categories, you’re not starting from a difficult position you’re starting from a refusal. The main routes are a dwelling on an active farm, a replacement dwelling, an infill site, or a dwelling within an existing cluster.
Two policies then catch a lot of otherwise reasonable schemes: ribbon development (adding to a line of houses along a road) and integration (whether the house sits properly into the landscape). People are consistently surprised by how broadly both get applied.
Donegal: do you meet the need?
In the Republic, one-off rural housing is assessed against the County Donegal Development Plan 2024–2030. And here’s where the border changes everything.
In the North, the question is mostly about your site. In Donegal, it’s largely about you. In the more restricted rural area types, you have to demonstrate a genuine housing need to live in that area commonly evidenced by you, or your parents or grandparents, having lived in the area for at least seven years. A statement won’t do it; the council will want proof.
Why this matters if you’re near the border
The two systems don’t just differ in detail. They ask completely different questions. A landowner who’d get permission on one side of the border can be a flat refusal a few miles away. Advice from a friend who built “just over the road” may be worse than no advice at all, because it sounds authoritative and it’s answering a different question entirely.
This is exactly why I work both systems and why, if you’ve got a rural site in mind, the single most valuable thing you can do is find out where it actually stands before you buy it.
Thinking about a rural site? A free Fit Call is fifteen minutes to see if we’re a match. If you’re further along, a Project Clarity Review gives you a written assessment of your specific site.
SITE BUYING
BUYING A SITE TO BUILD A HOUSE? SEVEN THINGS TO CHECK BEFORE YOU SIGN.
The most expensive mistake in any new house is the one you make before you own anything: paying good money for a site you can’t build the house you want on.
A field being for sale tells you nothing about whether it’s a building site. Here’s what to check first ideally before you sign, while you can still walk away for nothing.
Planning, before anything else. Is a house acceptable in principle here, under the policy that actually applies? In the North that’s the countryside policy categories; in Donegal it’s the rural housing need test. This is the one that kills most sites, so it goes first.
Access and sightlines. Can you form a safe entrance onto the public road, with the visibility the roads authority requires? Poor access has refused more rural applications than poor design ever has. And check whether the hedge, bank or wall you’d need to remove is actually yours to remove.
Wastewater. Most rural sites are off the public sewer, so you’ll need an on-site treatment system and the ground has to accept the discharge. In the Republic that means a percolation test to the EPA’s code of practice. If the ground fails, your options narrow fast, and on some sites there’s no solution at all. This test can end a project. Do it before you buy.
Water and services. Mains water or a well? How far is the electricity connection, and the broadband? On a remote site these are real costs, not rounding errors.
The ground and the exposure. Slope, wet ground, rock, flooding, orientation. Go and stand on the site in bad weather. Nearly every site here looks like a postcard on a still June evening; a fair few are a different animal in February with the wind off the Atlantic.
The whole budget, not just the build. Site, legal costs, groundworks, services, fees, contributions, fit-out, contingency. People routinely spend everything on the site and the dream and leave nothing to build well with.
What you’re actually allowed to do with it. Access rights, wayleaves, covenants on the title. Your solicitor earns their fee here.
None of these are expensive to check now. All of them are brutal to discover after the money’s gone.
EXTENSIONS
DO I NEED PLANNING PERMISSION FOR AN EXTENSION?
Maybe not but “maybe not” is exactly where people get caught. Some extensions can be built without a full planning application, but the rules are detailed, they’re different north and south of the border, and getting it wrong is expensive.
Northern Ireland: permitted development
In the North, certain extensions fall under permitted development rights, set by the Planning (General Permitted Development) Order (Northern Ireland) 2015. Important warning: most of what you’ll find online about “3-metre and 4-metre rules,” “8-metre extensions” or the “Larger Home Extension Scheme” is English law and does not apply here. If your search results are explaining prior approval for a 6m rear extension, you’re reading about somewhere else.
The Order sets limits on size, height, position and materials, and how much of the garden you can cover. Two things catch people most often: your allowance is measured from the original house as built, or as it stood in 1973 so if a previous owner extended, they’ve already used part of it. And Conservation Areas, AONBs and listed buildings all tighten the rules considerably.
Even where your extension is permitted development, it’s often worth applying for a Certificate of Lawful Development which is formal confirmation from the council that it’s lawful. When you sell, your buyer’s solicitor will want that evidence.
Donegal and the Republic: exempted development
In the South, the equivalent is exempted development. The headline rule: a rear extension can be exempt where it doesn’t increase the original floor area by more than 40 square metres.
But that’s a threshold, not the whole test and here’s the trap. The 40 sqm is cumulative and counts every extension since 1964, whether it had permission or not. A conservatory a previous owner added in the eighties has already eaten your allowance. There are also strict limits above ground floor, a requirement to keep 25 sqm of private open space, and window distance rules. Attic conversions are never exempt, and two-storey extensions effectively always need permission.
If there’s any doubt, you can apply to the council for a Section 5 declaration, a formal ruling on whether your proposal is exempt. It costs around €80 and it’s the cheapest certainty you’ll ever buy. Donegal county council have recently updated the exempted development regulations relating to extensions, garden rooms, ancillary dwellings and loft conversions so best to get in touch if you atre in any doubt.
The one rule that applies everywhere
Being exempt from planning does not exempt you from building control. They’re two separate systems. Even an extension that needs no planning at all still has to meet building regulations for structure, insulation, ventilation, fire and drainage. People conflate these constantly, and it’s the single most expensive misunderstanding I see.
STRATEGY
SHOULD YOU EXTEND, OR BUILD NEW?
It’s one of the most common questions I’m asked, and the honest answer is: it depends entirely on your house, your site and what you’re actually trying to fix. But there’s a way to think it through that gets you to the right answer faster.
Start with what’s actually wrong
Most people jump to a solution “we need an extension” before they’ve been precise about the problem. Is the house too small, or is it just badly arranged? Is the light wrong? Is it cold and expensive to run? Sometimes the answer isn’t more space at all; it’s reworking the space you’ve got, at a fraction of the cost. I’ve talked more than one person out of an extension and into a reorganization.
When extending makes sense
Extending usually wins when the existing house is fundamentally sound, you’re attached to the location, and the thing you need is achievable within what the site and the planning rules allow. A good extension isn’t just more floor area it fixes how the whole house works: the flow, the light, where everyone actually spends their time.
When building new makes sense
Building new starts to make sense when the existing house is in poor structural condition, hopelessly inefficient, or so badly suited to how you live that reworking it would cost nearly as much as starting again. There’s also knock-down-and-rebuild to consider, which sits between the two though be careful, because in planning terms a replacement dwelling has its own rules, and not every old house qualifies to be replaced.
The things people forget to weigh
Disruption. Extending means living in a building site, often for months. Building new usually doesn’t, if you’ve somewhere else to be.
The existing house always has a surprise in it. Old buildings hide things, no foundations where you expected, rot, historic alterations. That risk sits with extensions, not new builds.
Planning. An extension may be permitted or exempt development; a new house rarely avoids a full application, especially in the countryside.
The long game. Which option gives you the home you’ll actually want in twenty years not just the one that solves this year’s problem?
There’s no universal right answer. There’s only the right answer for your house, your site and your budget and working that out properly, before you commit to either path, is money extremely well spent.
FEES
WHY THE CHEAPEST DRAWINGS OFTEN COST YOU THE MOST
There’s always someone who’ll draw it cheaper. The question worth asking is what you’re actually buying because a set of drawings isn’t really the product. The thinking behind them is.
What a low fee usually means
A cheap fee almost always means the thinking got skipped. Nobody tested the brief against how you actually live. Nobody checked the planning position properly. Nobody thought hard about how it would be built, or made sure the structure, the drainage and the levels all agreed with each other.
It looks fine on paper. The problems come later.
Where it goes wrong
When a builder prices it. Drawings that ignore buildability and cost come back to bite the moment a real builder quotes. Suddenly the budget doesn’t work and you’re redesigning under pressure.
When planning or building control asks a question. A weak set of drawings sails along until someone official raises a point about policy, about a technical requirement, about a detail that doesn’t comply. Now you’re paying to fix it.
On site. Levels that weren’t checked. Drainage that wasn’t thought through. Structure that wasn’t coordinated. These don’t show up on a cheap drawing; they show up when the work’s underway and changing anything is at its most expensive.
Paying twice
The pattern is wearily consistent. People buy the cheap drawings, hit one of these walls, and end up hiring someone properly to sort it out. They’ve now paid for it twice, and lost months, and the second lot of money got spent in a hurry, which is the worst way to spend it.
None of this means dearest is best, or that you should never shop around. It means understanding what’s included, and being wary of a number that looks too good because the gap between it and the others is usually the thinking, and the thinking is the part that protects your budget.
You’re not really buying drawings. You’re buying someone’s judgement, and their willingness to tell you the truth before it costs you.
COST
WHAT ACTUALLY DRIVES THE COST OF BUILDING AND WHY I WON’T GIVE YOU A NUMBER OFF A WEBSITE
Building costs move quickly, so treat any figure you read online including any I might give as a rough guide with a short shelf life.
Everyone wants a number. I understand why. But the honest position is that a firm price per square metre, quoted cold off a website, is close to useless and often actively misleading. Costs have moved sharply in recent years with materials, labour and energy, and they vary enormously from one project to the next. So instead of a number that’ll be out of date by the time you read it, here’s what actually drives the figure. Understand these and you’ll be able to judge any quote you’re given far better than a headline rate ever could.
What moves the number
Specification. This is the big one. A simple, straightforward extension with modest finishes is one price. The same footprint with a lot of glazing, big structural openings, a high-end kitchen and top-tier finishes can be two or three times that. People routinely budget for the first and design the second, and that gap is where projects stall.
The existing house (for extensions). Extensions have to marry into a building that’s already there, with its own levels, drainage, structure and surprises. Connecting old to new is where “simple” jobs quietly get expensive.
The site (for new builds). A flat, dry, accessible site with services nearby is one thing. A sloping, wet or exposed site that needs groundworks, retaining and long service runs is another entirely before you’ve built a single wall.
How complete and detailed the drawings are. Vague drawings get padded quotes, because a builder prices the risk of what he can’t see. Clear, detailed drawings get you accurate, comparable prices. Good information is itself a way of controlling cost.
Everything that isn’t the building work. Professional fees, statutory costs, planning contributions (in the Republic), certification where BCAR applies, finishes, fit-out, and a contingency that isn’t optional. The build cost is the biggest single number, but it’s nowhere near the whole number.
Why the cheapest quote is rarely the real one
If one builder comes in well below the others, that’s rarely a bargain. It’s usually something missing, something assumed, or a price that will grow once the work has started and you’re committed. The lowest quote often hides the most.
The useful way to think about it
Rather than chase a per-square-metre figure, work out your total realistic budget, then design to it instead of designing something lovely and discovering later you can’t afford to build it. Getting that order right, early, is worth more than any cost calculator online.
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