Thermal Insulation and Energy Efficiency

In accordance with the EPBD, RE2020 and national regulations, external walls must achieve the required U-value (typically 0.15-0.30 W/m2K for new buildings, varying by climate zone). Insulation products must comply with EN 13162-EN 13171. Insulation must be continuous to minimise thermal bridges per EN ISO 10211. RE2020 imposes enhanced requirements for thermal performance and thermal bridge treatment.

1. Verify that insulation material and thickness match the thermal calculation

2. Check that insulation is continuous — no gaps at junctions, corners or around openings

3. Inspect for thermal bridges at structural elements (columns, beams, balconies)

4. Verify that insulation is correctly fixed (mechanical fixings, adhesive or both)

5. Use thermal imaging to detect insulation defects or thermal bridges

- Insulation gaps at wall-floor junctions creating thermal bridges

- Balcony connections without thermal break elements

- Insulation compressed or displaced during installation

- Insulation type unsuited to the application (moisture sensitivity)

In accordance with the EPBD and RE2020, roofs typically require U-values of 0.10-0.20 W/m2K and ground floors 0.15-0.25 W/m2K (varying by climate and national regulations). Vapour barriers must be placed on the warm side of the insulation per EN ISO 13788 to prevent interstitial condensation.

1. Verify that roof insulation thickness and material match the design

2. Check that the vapour barrier is on the warm side and continuous

3. Inspect insulation at eaves, verges and around roof penetrations

4. Verify floor insulation is correctly positioned (above or below slab)

5. Check for thermal bridges at wall-roof and wall-floor junctions

- Missing or insufficient insulation at eaves and roof edges

- Vapour barrier punctured by services or fixings

- Floor insulation crushed under heavy loads before slab casting

- Thermal bridge at parapet or wall plate

In accordance with the EPBD, EN 13829 and RE2020, building airtightness must be measured by blower door test. Typical requirement: air permeability <= 0.6 m3/(h.m2) at 4 Pa for individual houses and <= 1.0 m3/(h.m2) for collective housing (RE2020). For passive houses: <= 0.6 h-1 at 50 Pa (n50). Controlled ventilation must be provided per EN 15251 to ensure indoor air quality while maintaining energy efficiency. RE2020 mandates an air permeability test.

1. Verify that the air barrier membrane is continuous over the entire building envelope

2. Check sealing at all penetrations (pipes, cables, ducts) through the air barrier

3. Inspect sealing at window and door frames

4. Perform blower door test per EN 13829 — result must meet the target value

5. Verify that the mechanical ventilation with heat recovery (MVHR/VMC double flux) is installed and commissioned

- Air barrier not continuous — leaks at junctions and service penetrations

- Window and door frames poorly connected to the air barrier

- Blower door test failure due to unsealed penetrations

- MVHR not commissioned or filters not accessible for maintenance