Insulation and Airtightness Planning
- At this stage, your insulation and airtightness strategy should be finalized with your energy assessor.
- The most challenging parts of installation typically occur at junctions, such as between walls and roofs or around windows, where avoiding thermal bridging is key.
- For existing homes, unknown factors may arise, requiring adjustments to the original insulation and airtightness plan once certain elements are exposed.
Insulation Installation Options
- The type of insulation chosen will determine whether it can be installed as a DIY project or requires professional installers.
- For products like EPS beads and spray foam, manufacturers usually work with trained installers.
- External wall insulation often requires a professional, unless using a board or batt type that can be installed alongside brick or blockwork.
DIY Insulation Considerations
- Insulation boards or rolls can generally be purchased off the shelf and installed as a DIY project, with close attention to detail.
- Insulation is typically installed in two layers to ensure proper overlap at junctions.
- Correct installation is critical; any gaps in insulation can drastically reduce its effectiveness.
- Rolls should be laid out loosely without compacting, and boards must be joined neatly to avoid gaps, which can cause thermal looping.
- Always follow the manufacturer’s guidelines and check the product certification to ensure proper use.
Airtightness and Moisture Management
- Airtightness and condensation risk analyses should have been addressed during the design phase and must be followed precisely.
- Airtightness is not just about sealing the building but also about managing moisture levels to prevent buildup.
Product Selection and Strategy Adjustments
- Different construction methods require different approaches to airtightness and product use.
- If your builder suggests an alternative solution to achieve the same airtightness results, your energy assessor must approve the change and provide updated plans for the team to follow.
Monitoring Airtightness on Site
- For commercial buildings, airtightness inspectors are notified when any cuts are made to the airtightness membrane to ensure proper resealing.
- On a self-build project, it’s crucial to inform tradesmen that any cuts to the membrane must be reported to you or your builder.
Contractor vs. Direct Labour Oversight
- If you are managing the project using direct labour, you’ll need to keep an eye on insulation and airtightness installations.
- If you have hired a main contractor, they will oversee and ensure compliance with the airtightness and insulation plan.