Choose Your Wall System — Block, ICF, Timber Frame or SIPs for an Irish Self-Build

[@portabletext/react] Unknown block type "span", specify a component for it in the `components.types` prop

When this matters most

[@portabletext/react] Unknown block type "span", specify a component for it in the `components.types` prop

When this doesn't apply

[@portabletext/react] Unknown block type "span", specify a component for it in the `components.types` prop

Decision matrix

If: Site has poor access (narrow lane, low-loader limited)

Then: ICF or timber frame (delivered as panels, not pallets of block)

If: BER A1 is a must-have

Then: Timber frame or ICF (default with proper insulation)

If: Tight budget, standard site

Then: Blockwork with external insulation (cheapest warm wall)

If: Airtightness target is <1 m³/m²·hr

Then: ICF or SIPs (proven airtight at panel level)

If: Build on a remote site with no crane

Then: Timber frame (panelised) or SIPs

If: Want thermal mass

Then: Blockwork or ICF (concrete has mass; timber and SIPs do not)

If: Local trades are timber-frame-trained

Then: Timber frame (cheaper labour)

If: Local trades are block-trained

Then: Blockwork

Frequently asked questions

What's the cheapest wall system?

Blockwork with external insulation. €110–€160/m² of wall. Trades are everywhere, materials are stocked locally.

What's the warmest wall?

SIPs. U-value as low as 0.10 with standard 200 mm panel. Timber frame and ICF both reach 0.13–0.18 with normal build-up.

Which wall system is fastest to build?

SIPs and timber frame, both at 2–4 weeks for walling on a 150 m² house. ICF is 3–5 weeks. Blockwork is 6–9 weeks.

Can I get BER A1 with any wall system?

Yes, if insulation and airtightness details are right. Timber frame and ICF make it easiest; SIPs and CLT make it cheapest in design effort.

Do mortgage lenders care which system?

Generally no, but some have preferred suppliers or a panel of approved frames. Confirm with your lender before detailed design.

Sources

Building Regulations 2023, TGD Part L (Conservation of fuel and energy — Dwellings), Department of Housing. https://www.gov.ie/

NSAI, I.S. EN ISO 13790 — Energy performance of buildings. https://www.nsai.ie/