Dublin Building
Intelligence Repository.
20 in-depth architectural, statutory, and financial guides written by Master Builder Sérgio Gratival. Designed to give Dublin homeowners and RIAI architects total clarity on planning exemptions, structural steel engineering, BCAR compliance, and realistic 2026 build costs.
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Filter instantly across all 20 guides by typing RSJ, costs, 40m², or SEAI:
How the 40m² Planning Exemption Works in Dublin: Complete Homeowner Guide (2026)
"Under Section 4(1)(a) and Class 1 of the Planning and Development Regulations 2001 (as amended), Dublin homeowners can extend up to 40m² (430.5 sq. ft) to the rear without planning permission, provided at least 25m² of private garden is retained, the roof does not exceed original eaves height, and prior extensions count cumulatively."
When Do You Need Planning Permission for a Home Extension in Dublin? (Exempt vs Non-Exempt)
"You must apply for full planning permission in Dublin if your extension exceeds 40m², leaves less than 25m² of rear garden, extends past the front or side building line, breaches eaves height, is in an Architectural Conservation Area (ACA), or alters a Protected Structure."
Two-Storey House Extensions in Dublin: Planning Rules, Boundary Setbacks & Overlooking Laws
"Two-storey extensions in Dublin are permitted under exemption ONLY if total combined floor area does not exceed 40m², first-floor walls are at least 2 metres from opposite boundaries, and rear garden retains at least 25m². Extensions exceeding these dimensions require full planning permission."
Renovating a Protected Structure or Period Red-Brick in Dublin: Section 57 Declarations
"Protected Structures in Dublin have NO automatic planning exemption rights. Even minor alterations require a Section 57 Declaration or full conservation planning permission. Works must employ breathable lime mortars, reversible structural steel, and preserve historical brickwork."
Party Wall Agreements & Boundary Excavations in Dublin: Section 44 Legal Framework
"Under Chapter 3 of the Land and Conveyancing Law Reform Act 2009, homeowners have the right to carry out works to party structures, provided statutory notice is given, schedule of condition is recorded, and any damage is made good at the building owner's expense."
How Much Does a Home Extension Cost in Dublin in 2026? Realistic Price per Square Metre Guide
"In Dublin in 2026, standard to high-end architectural residential extensions cost between €2,200 and €3,400 per square metre (ex. VAT at 13.5%). A turnkey 40m² rear extension typically ranges from €105,000 to €155,000 depending on structural steel, glazing format, and ground conditions."
7 Hidden Costs in Dublin Home Extensions (And How to Avoid Contractor Variations)
"The 7 most frequent budget surprises in Dublin extensions are: main sewer diversions (€3k–€8k), structural padstones under existing foundations (€2k–€5k), electrical consumer unit upgrades (€2.5k), party wall schedules (€1.5k), radon sumps (€1k), skips/parking permits (€1.5k), and engineer certs (€3k)."
Back-to-Brick Renovation Costs in Dublin: 2026 Budget Breakdown for 3 & 4-Bed Homes
"A full back-to-brick renovation in Dublin for a typical 3-bed semi (110m² to 140m²) ranges from €180,000 to €280,000 (€1,500 to €2,000/m²). For a 4-bed detached house (160m² to 220m²), budgets range from €260,000 to €420,000+."
Cost of Knocking Down a Load-Bearing Wall & Installing an RSJ Steel Beam in Dublin (2026)
"In Dublin, knocking through an internal load-bearing wall and installing an RSJ steel beam typically costs between €4,500 and €11,500 depending on beam span, temporary works propping, padstone foundations, and ceiling recess requirements."
Architects' Fees vs. Master Builder Turnkey Contracts in Dublin: Value & Cost Comparison
"Full architectural services in Dublin typically cost 10% to 15% of the total build cost (€25k to €45k on a €300k project). A master builder turnkey contract with partnering architect can reduce design overheads by 40% while maintaining complete RIAI contract integrity."
Structural Steel RSJ Beams in Dublin Extensions: Sizing, Padstones & Open-Plan Vistas
"Long open-plan spans in Dublin (6m to 9m) require heavy structural steel sections (e.g. 254x146 UB or 203x203 UC) designed to Eurocode 3, with reinforced concrete padstones distributing thousands of kilograms of ceiling and roof load safely into ground masonry."
Flat Roof vs. Pitched Roof for Dublin Home Extensions: Cost, Lifespan & Roof Lanterns
"Warm flat roofs with frameless glass roof lanterns provide higher internal ceiling heights and contemporary aesthetics at 15% to 20% lower cost than pitched roofs, while natural slate pitched roofs offer 60+ year durability and blend seamlessly with period properties."
Underfloor Heating in Home Extensions: Liquid Screed vs Sand-and-Cement in Dublin
"Flowing liquid screed can be laid thinner (45mm vs 75mm), completely wraps around PEX heating pipes with zero air voids, offers 2x higher thermal conductivity (2.2 W/mK), and responds twice as fast to heat pump temperature calls."
Dublin Soil Conditions & Foundation Types: Strip Foundations vs Piling for Rear Extensions
"While standard Dublin boulder clay supports traditional 1.0m deep reinforced concrete strip footings, soft alluvial soils near Dublin Bay or proximity to large mature trees requires engineered mini-piled foundations with ground beams."
Slimline Sliding Patio Doors vs. Bi-Fold Doors in Dublin: Thermal U-Values & Security
"In Dublin's windy and wet maritime climate, large-panel sliding patio doors (with 20mm slim sightlines) offer superior weather tightness, lower thermal U-values (0.8 W/m²K triple glazed), and uninterrupted garden views compared to multiple bi-fold frame joints."
BCAR Explained for Dublin Homeowners: S.I. 9 Building Control Regulations & Opt-Out Rules
"BCAR requires statutory inspection plans, Ancillary Certifications, and a Certificate of Compliance on Completion registered on the national BCMS database. While single-dwelling extensions can legally 'opt out' of administrative paperwork, the physical build MUST still comply 100% with Building Regulations Part A through M."
How to Bring a 1970s Dublin House from BER E/D to BER A2 (Deep Retrofit Guide)
"Achieving a BER A2 rating requires a 'fabric first' approach: external wall insulation (U-value ≤ 0.18 W/m²K), 400mm attic insulation, triple glazing, airtightness membrane (< 1.5 ACH @ 50Pa), mechanical heat recovery ventilation (MVHR), and an air-to-water heat pump."
SEAI Grants Guide 2026: Claiming up to €25,000 for Home Extensions & Insulation in Dublin
"In 2026, Dublin homeowners can access up to €25,000 in non-repayable SEAI grants for energy retrofits: €6,500 for heat pumps, up to €8,000 for external wall insulation, €2,100 for solar PV, and €1,500 for heating controls."
Thermal Bridging & Mold Prevention: Technical Insulation Details for Dublin Home Extensions
"Thermal bridging occurs where steel beams or concrete lintels penetrate the insulation envelope. In Dublin's damp winter climate, this causes cold spots, surface condensation, and toxic black mold. Prevention requires continuous insulation wrapping (psi-values ≤ 0.08 W/mK) and thermal break connectors."
How to Check a Dublin Builder Before Signing: CIRI Registration, Safe Pass & Insurance Verification
"Before transferring any funds, verify your Dublin contractor's 5 core credentials: 1) Active CRO company registration, 2) Revenue eTax Clearance Access Code, 3) Verified €6.5M Public Liability insurance schedule naming you as indemnified, 4) FAS/SOLAS Safe Pass cards for all site workers, and 5) Fixed-price RIAI Domestic Building Contract."
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