Tips for House Extensions and Renovations in Dublin 2025

A single-storey extension typically takes 12-16 weeks from groundworks to completion. A two-storey extension usually requires 16-24 weeks. However, timelines can vary based on:

• • Size and complexity of the project
• • Weather conditions (particularly during winter months)
• • Availability of materials and tradespeople
• • Any unforeseen structural issues discovered during construction

These timelines don't include the pre-construction phase (design, planning permission if needed, and contractor selection), which can add 2-4 months.

Many extensions can be built under "exempted development" without formal planning permission, provided they meet specific criteria:

• • Maximum 40m² (including previous extensions)
• • At the rear of the property
• • Not exceeding the height of the existing house
• • Maintaining 25m² of private open space
• • Not a protected structure or in a conservation area

However, you still need to comply with Building Regulations and may need to submit a Commencement Notice. We recommend consulting with an architect or our team to confirm whether planning permission is required for your specific project.

Most homeowners can remain in their property during a house extension, though there will be some disruption. Here's what to expect:

• • Noise and dust during working hours (typically 8am-5pm, Monday-Friday)
• • Temporary loss of access to certain areas
• • Possible brief interruptions to utilities during connection work
• • Construction traffic and materials deliveries

We take measures to minimize disruption, including setting up dust barriers, maintaining clean work areas, and providing clear communication about each phase. Some families choose to stay with relatives during the noisiest phases (demolition and groundworks), but this typically isn't necessary for the entire build.

Extension costs in Dublin vary significantly based on size, specifications, and finishes:

• • Single-storey extension: €2,500-€3,500 per m²
• • Two-storey extension: €2,200-€3,000 per m²
• • Attic conversion: €40,000-€70,000 complete

These are inclusive prices covering construction, materials, and standard finishes. Premium materials, architectural features, or complex structural work will increase costs. Don't forget to budget for:

• • Professional fees (architect, engineer): 8-12% of construction costs
• • Planning and Building Control fees: €500-€1,500
• • Contingency fund: 10-15% for unexpected issues

Yes, absolutely! Semi-detached and terraced houses can be extended, but there are additional considerations:

Party Wall Considerations:

• • You must inform your neighbors of your plans in writing
• • If your extension affects a shared wall, you may need a Party Wall Agreement
• • Professional advice from a structural engineer is recommended

Space Limitations:

• • Terraced properties often have limited rear garden space
• • You must maintain adequate private open space (minimum 25m²)
• • Side extensions are usually not possible on terraced houses

We have extensive experience extending semi-detached and terraced properties throughout Dublin, including managing neighbor relations and maximizing available space.

Yes, a well-designed and professionally built extension typically adds significant value to your property. Based on Dublin market trends:

• • Additional bedroom: Can add 10-15% to property value
• • Kitchen extension: Often returns 70-80% of investment immediately
• • Two-storey extension: Can increase value by €80,000-€150,000
• • Attic conversion: Typically adds €40,000-€70,000 to value

Return on investment is highest when:

• • The extension is proportionate to the property (don't over-extend on a small house)
• • Quality of finish matches or exceeds the existing property
• • Design is sympathetic to the neighborhood and enhances curb appeal
• • You're in a desirable Dublin area with strong property demand

Even if you don't sell immediately, you'll enjoy the improved living space and functionality every day.

While extensions can be built year-round in Dublin, timing can affect your experience:

Spring (March-May):

• • Ideal weather for groundworks and foundation work
• • Longer daylight hours = more productive work days
• • High demand for contractors - book early

Summer (June-August):

• • Best weather conditions for construction
• • Faster drying times for concrete and renders
• • Easier to manage disruption when children are off school
• • Peak season - highest contractor demand and prices

Autumn (September-November):

• • Still good weather conditions
• • Slightly lower demand than summer
• • Aim to complete before winter

Winter (December-February):

• • Lower contractor demand - potential cost savings
• • Weather can cause delays
• • Shorter daylight hours
• • Not ideal for groundworks in freezing conditions

Our advice: Start planning in winter/early spring, get approvals sorted, and aim to begin construction in spring or early summer for optimal conditions.