Cavity, Wrap or Dry Lining: Which Dublin Wall Job Fits Your House

Dublin walls fail in three different costumes. Some are hollow and pumpable. Some are solid and need a coat on the outside. Some keep the outside brick and put the insulation on the inside. The wrong costume wastes a survey morning. The right one is a short table, not a metaphor.

Start with the wall you actually have

Before anyone talks euros, open a door reveal or a window reveal and measure the wall thickness. A true cavity wall is usually about 270–300 mm with two leaves and a gap. Many 1930s–1970s Dublin semis and terraces sit in that band. Older solid walls and some hollow-block builds are a different job. SEAI’s insulation upgrade guide still frames walls as a major heat-loss path alongside the roof — see the public overview on SEAI’s insulation upgrades page. That is fabric physics, not a promise that every Direct Debit halves overnight.

If the cavity is clear and wide enough, pumping it is usually the least disruptive of the three. If there is no useful cavity, or the cavity is already filled or contaminated, you are looking at a wrap or at internal lining. Match the costume to the wall you have, not to the neighbour’s Facebook quote.

Side-by-side: cavity vs wrap vs dry lining

Those grant figures are SEAI Better Energy Homes individual amounts for wall measures, increased from early 2026 and published on SEAI’s wall insulation grant page inside the wider home energy grants set. Mention once. Enhanced welfare rates and second-wall rules live on SEAI — do not invent a you-pay remainder for a wrap from a blog table.

How to read the table without fooling yourself

Cavity is cheap disruption, not magic. If the wall is under about 270 mm at the reveal, or boroscope shows rubble, damp, or an old fill, pumping is the wrong costume. A wrap is the grown-up answer for many solid Dublin walls: continuous insulation outside, thermal bridges cut at the reveals, and a finished coat that can also tidy tired render. Dry lining keeps the street face and spends your space instead. Passive House Plus still covers fabric-first thinking for Irish stock if you want a deeper technical read at Passive House Plus.

Climate and moisture matter. Dublin winters are damp and cool whether or not your wall is insulated. Neither Met Éireann nor the EPA will tell you which of the three columns fits your mid-terrace in Crumlin — a survey will. Energy bill noise will keep scrolling through The Irish Times Environment; your wall type will not change with the headlines.

Sequence still beats a single costume

Walls are one lever. Attic first still makes sense in most Dublin sequences because the residual after an attic grant is small and heat rises — see Monday’s short arithmetic on €300 after-grant attic versus five winters. Pull your own meter trail from ESB Networks meters and readings before you argue with a blog average. Product standards and installer paperwork sit under NSAI and SEAI registration rules — registration still gates the grant claim. For a news backdrop on home energy costs, RTÉ News keeps the wider story visible without changing your wall type.

Pre-2011 occupancy rules still gate individual wall grants. Approval first. If SEAI does not approve, Retrofit Dublin does not start the work and you pay nothing under the grant guarantee. That is the same promise as attic work — walls do not get a special exemption.

Use the table as a filter, not a quote. A 1980s semi with a clear cavity is rarely an EWI conversation on day one. A solid redbrick terrace with no cavity is rarely a pump conversation. Hollow-block quirks need a boroscope, not a suburb name. When you want the wall costume named for your house and Claim Your Grants started properly, call 01-233-7477 or open the home energy upgrades hub and go straight to external wall insulation Dublin if the wrap column is the one that fits.