Choosing the Right Insulation for Your Home

Proper insulation is the foundation of an energy-efficient home. This guide helps you understand the different types of insulation available and choose the right solution for your property.

Why Insulation Matters

Up to 30% of your home's heat can be lost through uninsulated or poorly insulated areas. Good insulation:

• Reduces heating bills significantly
• Improves home comfort
• Reduces carbon emissions
• Increases property value
• Helps qualify for other energy grants

Types of Insulation

Attic Insulation

Best for: Most homes, especially older properties

Attic insulation is often the most cost-effective upgrade:

• Materials: Mineral wool, cellulose, or rigid boards
• Thickness: Typically 300mm recommended
• Cost: €500 - €1,500 depending on attic size
• Grant: Up to €1,500 from SEAI

Considerations:
- Ensure adequate ventilation
- May need to raise floor if using attic for storage
- Professional installation recommended

Cavity Wall Insulation

Best for: Homes built between 1920-1990 with cavity walls

Cavity wall insulation fills the gap between inner and outer walls:

• Materials: Mineral wool, polystyrene beads, or foam
• Installation: Holes drilled in external walls, material injected
• Cost: €1,000 - €2,500
• Grant: Up to €1,200 from SEAI

Considerations:
- Only suitable for homes with cavity walls
- Requires professional assessment first
- Can cause damp if not done correctly

External Wall Insulation

Best for: Solid wall homes or when renovating exterior

External wall insulation involves adding insulation to the outside of your home:

• Materials: Insulated render systems
• Installation: Applied to external walls, then rendered
• Cost: €8,000 - €15,000 depending on house size
• Grant: Up to €6,000 from SEAI

Considerations:
- Most expensive option
- May require planning permission
- Transforms exterior appearance
- Very effective for solid wall homes

Internal Wall Insulation

Best for: When external insulation isn't possible

Internal wall insulation is applied inside your home:

• Materials: Insulated plasterboard or boards
• Installation: Fixed to internal walls
• Cost: €3,000 - €8,000
• Grant: Up to €4,500 from SEAI

Considerations:
- Reduces room size slightly
- Requires moving fixtures
- Less effective than external insulation

Choosing the Right Type

For New Builds

• External wall insulation (if budget allows)
• High-performance attic insulation
• Floor insulation
• Consider Passivhaus standards

For Older Homes (Pre-1990)

1. Start with attic insulation (cheapest, biggest impact)
2. Add cavity wall insulation if applicable
3. Consider external wall insulation for solid walls
4. Upgrade windows and doors

For Period Properties

• Internal wall insulation to preserve exterior
• Attic insulation
• Floor insulation
• Careful ventilation planning essential

Insulation Materials

Mineral Wool

• Pros: Fire resistant, good soundproofing, easy to install
• Cons: Can be itchy during installation
• Best for: Attics, cavity walls

Cellulose

• Pros: Eco-friendly, good for irregular spaces
• Cons: Can settle over time
• Best for: Attics, hard-to-reach areas

Polystyrene Beads

• Pros: Good for cavity walls, doesn't settle
• Cons: Less eco-friendly
• Best for: Cavity wall insulation

Rigid Boards

• Pros: High performance, thin profile
• Cons: More expensive
• Best for: External wall insulation, floors

SEAI Grants

The SEAI offers grants for various insulation types:

• Attic Insulation: Up to €1,500
• Cavity Wall: Up to €1,200
• External Wall: Up to €6,000
• Internal Wall: Up to €4,500
• Dry Lining: Up to €3,500

Grants are typically 50-80% of the installation cost.

Installation Considerations

Professional Installation

Always use qualified installers:

• SEAI registered for grant eligibility
• Proper training and certification
• Insurance and warranty coverage
• Knowledge of building regulations

Ventilation

Good insulation must be paired with proper ventilation:

• Prevents condensation and damp
• Maintains air quality
• Protects building structure
• May require ventilation upgrades

Building Regulations

Ensure compliance with:

• Building regulations
• Fire safety requirements
• Planning permission (for external insulation)
• BER improvement requirements

Cost vs. Benefit

Quick Wins

1. Attic Insulation: Low cost, high impact
2. Draught Proofing: Very low cost, immediate comfort
3. Hot Water Cylinder Jacket: Minimal cost, good savings

Medium Investment

1. Cavity Wall Insulation: Good payback period
2. Floor Insulation: Effective for ground floors
3. Window Upgrades: Secondary glazing or replacement

Major Investment

1. External Wall Insulation: Highest impact, highest cost
2. Complete Retrofit: Multiple measures together
3. Passivhaus Standard: Maximum efficiency

Common Mistakes to Avoid

1. Insufficient Thickness: Don't skimp on insulation depth
2. Poor Installation: Always use qualified installers
3. Ignoring Ventilation: Can cause serious damp problems
4. Wrong Material: Choose appropriate material for each area
5. Missing Areas: Insulate comprehensively, not selectively

Conclusion

Choosing the right insulation depends on your home type, budget, and goals. Start with attic insulation for the best cost-benefit ratio, then consider wall insulation based on your home's construction. Always work with SEAI registered installers to ensure quality work and grant eligibility. Proper insulation is an investment that pays back through lower bills and increased comfort.