Solid walls can be insulated either externally or internally. Each approach has its advantages, and the choice depends on the specific needs and constraints of your property. Read on to find out more about the merits of each, when one should be used, and the benefits of the SWIP IWI system.
Internal Wall Insulation (IWI)
Internal wall insulation involves the installation of metal or timber studs with insulation placed between them, covered with a vapor control layer and plasterboard. Alternatively, thermal laminate boards or rigid insulation boards can be mechanically fixed to the walls.
It is essential that IWI systems are not used to conceal or isolate moisture penetration or damp problems in the existing structure. Insulating internally improves thermal performance without altering the external appearance of the building. However, this method may slightly reduce the internal floor area by approximately 1-2%.
The SWIP IWI System is designed for minimal disruption to occupants, ease of installation, and alignment with BEIS guidance. It doesn’t require scaffolding, preserves the building’s external appearance, and offers flexibility during refurbishments.
External Wall Insulation (EWI)
External wall insulation systems typically consist of an insulation layer that is mechanically or adhesively fixed (or both) to the existing wall, followed by a render coat. Other finishes such as timber boarding, concrete or clay tiles, or metal cladding can also be applied. This type of insulation can significantly enhance a property’s appearance.
However, planning permission and compliance with Building Regulations may be required before installation. Particular attention must be paid to elements like window sills, rainwater downpipes, gutters, and eaves. Adjustments to the roofline may be necessary to accommodate the added thickness of the system.
Advantages of Internal Wall Insulation
Internal wall insulation offers several advantages over external wall insulation:
- Lower installation cost.
- Easier maintenance.
- No scaffolding required.
- Preserves external appearance, making it suitable for conservation areas.
- Readily available materials.
- Flexible installation, allowing for room-by-room or whole-house application.
- Unaffected by weather delays.
Thermal Comfort
IWI enables rooms to reach comfortable temperatures more quickly than EWI systems. This reduces heating time and costs, particularly in intermittently heated buildings like homes.
Best Time to Install Internal Insulation
The ideal time to install internal wall insulation is when other work is already planned, such as replacing crumbling plaster, redecorating, rewiring, installing central heating, or during full refurbishment. Before installation, remedial work like adding a damp-proof course or repairing guttering should be completed. The system should not be used to conceal damp or wet walls.
Benefits of Solid Wall Insulation
Installing internal wall insulation provides numerous benefits:
- Reduced CO₂ emissions.
- Lower energy bills.
- Enhanced thermal comfort.
- Decreased risk of condensation and mould growth.
Taking advantage of any opportunity to improve your home’s energy efficiency can lead to a more comfortable and sustainable living environment.
Solid walls can be insulated either externally or internally. Each approach has its own advantages, and the choice depends on the specific needs and constraints of your property. Read on to find out more about the merits of each, when one should be used, and the benefits of the SWIP system.
