U-values for Scotland — Section 6

Scotland's Building Standards set their own U-value tables, and they are not the English Part L figures. Here are the January 2025 numbers, where they come from, and a free calculator that applies them.

Completely free — choose Scotland under the verdict and the tables switch.

Calculate a U-value — Scotland

Opens on a wall with the Scottish dwelling tables selected. Change the nation or building type at any time.

Dwellings — Domestic Technical Handbook, January 2025

Standard 6.2 sets maximum area-weighted U-values for every element of the insulation envelope (Table 6.2, clause 6.2.1). Unlike England, one table serves new buildings, extensions and conversions alike. Standard 6.1 then requires a SAP 10 calculation against a notional dwelling (Table 6.1), whose fabric is tighter — that is the level a fabric-first design is really aiming at.

ElementTable 6.2 maximumTable 6.1 notional dwellingIndividual area / after reconstruction
Wall0.170.150.70
Floor0.150.120.70
Roof0.120.090.35
Windows, roof windows, doors1.41.23.3 (glazing)
Rooflights2.11.73.3 (glazing)
Cavity separating wall0.00.0 (party walls)

All values W/m²K. Sources: Domestic Technical Handbook, January 2025 edition, clause 6.2.1 Table 6.2 (p.464), clause 6.1.2 Table 6.1 (p.458), clause 6.2.10 (p.473). Applicable to warrants from 1 January 2025; Section 6 is unchanged in the April 2026 edition.

Non-domestic — Non-domestic Technical Handbook, January 2025

ElementTable 6.3 maximumIndividual area / after reconstruction
Wall0.210.70
Floor0.180.70
Roof0.160.35
Windows and roof windows1.63.3
Rooflights2.23.3
Pedestrian doors1.4

Source: Non-domestic Technical Handbook, January 2025 edition, clause 6.2.1 Table 6.3 (p.476); extensions (6.2.9) and reconstructed elements refer back to it. There is no per-element notional: compliance is BDER ≤ TDER in SBEM against the NCM notional building.

The same wall, judged three ways

A partial-fill cavity wall — 102.5 mm brick, 50 mm residual cavity, 100 mm PIR (λ 0.022), 100 mm dense block and plasterboard — calculates to 0.20 W/m²K with the standard air-gap correction. In England it passes the dwelling backstop of 0.26 (amber: short of the 0.18 notional). In Wales it fails the 0.18 maximum. In Scotland it fails the 0.17 maximum for a dwelling but passes the 0.21 non-domestic maximum. Swap the PIR for 150 mm of full-fill mineral wool (λ 0.032) on aircrete and it lands at 0.18 — still short of Scotland's 0.17. That is why the calculator asks where the building is before it says pass or fail.

How U-Monkey applies it

Pick Scotland and Dwelling or Non-domestic under the verdict. New build is judged against the Table 6.2 (or 6.3) maximum with the Table 6.1 notional shown alongside; a new element in an extension or conversion against the same table; an existing element as built against the 0.70 / 0.35 threshold; a reconstructed element against the Table 6.2 benchmark with the threshold as the floor. Windows and doors entered as specified elements use the same tables. The free PDF names the handbook, table and edition in the verdict banner and the footer.

Frequently asked questions

What U-values does Section 6 require for a new house in Scotland?

Two sets. Table 6.2 of the Domestic Technical Handbook (January 2025 edition) sets the maximum area-weighted U-values: walls 0.17, floors 0.15, roofs 0.12, windows, roof windows and doors 1.4, rooflights 2.1 W/m²K. Compliance with Standard 6.1 is then shown in SAP 10 against a notional dwelling with walls 0.15, floors 0.12, roofs 0.09, windows and doors 1.2 and rooflights 1.7 (Table 6.1) — so a fabric-only design usually needs to be nearer the notional figures than the maxima.

Are the Scottish targets different for extensions and conversions?

Not in the way England’s are. Scotland uses the same Table 6.2 maxima for new buildings, extensions (clause 6.2.8) and conversions (6.2.6). What changes is the fallback: where those values are not reasonably practicable in existing fabric, individual areas may be no worse than 0.70 for walls and floors and 0.35 for roofs, and a reconstructed element should achieve at least those figures (6.2.10).

Does U-Monkey use the Scottish tables?

Yes. Under the verdict, choose Scotland and either Dwelling or Non-domestic; the pass/fail, the hint text and the PDF footer switch to Section 6 and name the table used. The U-value itself is the same BS EN ISO 6946 calculation as everywhere else in the UK.

What about non-domestic buildings in Scotland?

The Non-domestic Technical Handbook’s Table 6.3 sets walls 0.21, floors 0.18, roofs 0.16, windows and roof windows 1.6, rooflights 2.2 and pedestrian doors 1.4 W/m²K, with the same 0.70 / 0.35 individual-area rule. Compliance for a new building is a BDER ≤ TDER calculation in SBEM against the NCM notional building rather than a per-element notional.

Is the 2022 online handbook still right?

No — the HTML clause pages Google still serves are the 2022 edition, whose notional walls were 0.17 with fuel-specific packages. The energy standards changed in February 2023 and the current figures above are from the January 2025 PDF edition, which is the one in force.

Elsewhere in the UK: Wales (Part L 2022) · non-domestic buildings · England dwellings. Full tutorial: how to use U-Monkey.

Judge your build-up against Section 6, not Part L.

U-Monkey traffic-lights your wall, roof or floor against Table 6.2 and the Table 6.1 notional dwelling (or Table 6.3 for non-domestic work), names the table on the PDF, and is free.