Midland Insulation — Technical Glossary

Plain-English glossary of 15 cavity wall, attic mineral wool, external wall wrap, U-value and SEAI grant terms in Ireland.

15 key terms explained

Bonded Graphite EPS Cavity Bead

Silver-grey expanded polystyrene beads coated in a breathable bonding agent and injected into masonry cavity walls so they set into a stable, water-resistant thermal core.

U-Value (W/m²K)

The rate of heat transfer through 1 m² of a wall or roof for every 1°C temperature difference; lower U-values mean better insulation (0.16 W/m²K for attics, 0.27 W/m²K for external wrap).

300mm Cross-Laid Attic Mineral Wool

Two-layer roof insulation layout placing 100mm mineral wool between the ceiling joists and 200mm across the tops of the joists to eliminate thermal bridging through the timber.

Eaves Ventilation Baffle (Raflavan Tray)

Corrugated plastic vent tray stapled between the rafters at the eaves to keep a 50mm clear airway into the attic above the 300mm insulation.

External Wall Insulation (ETICS / The Wrap)

Composite external insulation system combining 100mm to 150mm EPS or mineral wool boards, mechanical dowel fixings, reinforced basecoat mesh and breathable silicone render.

Internal Insulated Dry-Lining

Fixing insulated plasterboard (thermal laminate) or a mental stud frame with mineral wool and a vapour-control layer to the inside face of external walls.

Thermal Bridging (Cold Bridging)

Heat loss through uninsulated structural junctions such as concrete window lintels, sills and ceiling joists where damp condensation spots can form.

Window Reveal Insulation Board

High-density 20mm to 30mm phenolic or XPS board fitted around window and door returns during an external wrap so heat does not escape around the frame.

NSAI Agrément Certificate

Official certification issued by the National Standards Authority of Ireland confirming an insulation material and system is tested for Irish wind-driven rain conditions.

S.R. 54 Code of Practice

The Irish standard for the energy retrofit of existing dwellings, governing moisture management, wall breathing and room ventilation.

Core Hole Extraction & Borescope Survey

Drilling 22mm inspection holes and using a fibre-optic camera to check wall cavity width, mortar snots, wall ties and any old rubble before pumping.

Vapour Control Layer (VCL)

A warm-side membrane fitted behind internal dry-lining plasterboard to stop warm indoor moisture condensing inside the cold wall structure.

Raised Loft Storage Deck

Insulated leg supports screwed to the ceiling joists that hold chipboard flooring above 300mm of uncompressed attic wool.

MPRN (Meter Point Reference Number)

Your 11-digit ESB Networks electricity meter number used by SEAI to verify the house address and pre-2011 build date.

Post-Works BER Certificate

The official Building Energy Rating assessment completed after your insulation upgrade is finished, required by SEAI to release the grant payment.