# Footing Depth & Frost Rules Compared: 14 Countries, Mostly No Fixed Number Minimum footing depth and frost-line rules compared across 14 countries — the one category where 'no fixed figure' is the norm, plus the two exceptions: India's flat 500mm and Japan's 240mm. - Canonical HTML: https://www.chippy.tools/articles/footing-depth-and-frost-rules-by-country/ - Publisher: Chippy Tools - Language: en - Updated: 2026-11-09 # Footing Depth & Frost Rules Compared: 14 Countries, Mostly No Fixed Number Sam Petherbridge · Qualified Carpenter & Builder Updated November 9, 2026 Of the four comparisons we’ve run across our 14 countries — stairs, ceilings, ramps and now footings — this is the one where “no fixed figure” isn’t the exception, it’s the norm. Eight of the fourteen countries — New Zealand, Ireland, France, Germany, Spain, Indonesia, Norway and Sweden — explicitly defer minimum footing depth to a site investigation or a full Eurocode design process, with zero mandated centimetre figure in the national code. Only two countries buck that trend with a genuinely fixed nationwide depth: India, at a flat 500 mm, and Japan, at a 240 mm strip-footing embedment. Here’s how all fourteen actually handle it. ## Minimum footing depth & frost rule, by country | Country | Minimum depth / frost rule | Governing standard / clause | |--------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | Australia | **No fixed depth figure** — table/site-classification driven under AS 2870; 300 mm below finished ground level applies only on loose, erosion-prone sand | [NCC 2025 Housing Provisions 4.2.2–4.2.3](https://ncc.abcb.gov.au/editions/ncc-2025/adopted/housing-provisions/4-footings-and-slabs/part-42-footings-slabs-and-associated-elements) | | USA | 12 in / 305 mm minimum below grade (non-frost baseline); **frost-line depth is set locally** — the model code table is deliberately left blank for each jurisdiction to fill in | [IRC 2021 R403.1.4 / R403.1.4.1](https://up.codes/viewer/connecticut/irc-2021/chapter/4/foundations) | | New Zealand | 200 mm minimum embedment OR to “good ground,” whichever is greater. **No frost-depth concept at all** — frost heave is instead handled by excluding any ground liable to ≥25 mm movement from the “good ground” definition | [NZS 3604:2011 s7.5](https://www.aucklandcouncil.govt.nz/content/dam/ac/docs/building-and-consents/ac2208-foundation-depth-for-buildings-outside-the-scope-of-nzs3604-2011.pdf) (via NZBC B1/AS1) | | UK (England) | 450 mm minimum (frost, non-clay); 750/900/1000 mm on low/medium/high-shrinkage clay | [Approved Document A (2013), para 2E4](https://assets.publishing.service.gov.uk/media/5a80437640f0b623026927b2/BR_PDF_AD_A_2013.pdf) | | Canada | Rock/coarse-grained soil: no limit. Clay/undefined soil: 1.2 m. **Frost depth itself is a local figure** — not a national NBC number | [NBC 2020 Table 9.12.2.2](https://free.bcpublications.ca/civix/document/id/public/bcbc2018/bcbc_2018dbp9s912) | | Ireland | **No fixed depth or frost-line figure** — set by ground/site investigation; width is table-driven (400–650 mm band) | [TGD Part A 2012, par. 1.1.5.1–.3](https://www.gov.ie/en/publication/9d5d1-technical-guidance-document-a-structure/) | | France | **No fixed national depth.** A climate-zone “hors-gel” (frost-free) system applies, but neither dual-verification pass could confirm a matching cm figure from primary text — no number ships | NF DTU 13.1 / NF P 94-261 — paywalled, no free primary URL | | Germany | **No fixed national depth.** DIN 1054 gives 0.80 m as a general baseline assumption only; actual depth is site-determined, commonly 0.80–1.50 m in practice | DIN EN 1997-1 (Eurocode 7) + DIN 1054 — paywalled, no free primary URL | | Spain | **No fixed depth or frost-line figure** for an ordinary shallow footing — set by geotechnical study. (0.80 m applies only to retaining/basement walls, a different element.) | [CTE DB-SE-C §4.2–4.3](https://www.codigotecnico.org/pdf/Documentos/SE/DBSE-C.pdf) | | Indonesia | **No fixed depth, and no frost concept at all** (tropical climate) — depth set entirely by site/bearing-capacity investigation | [Permen PU 29/2006, Bab III.3.1.d](https://peraturan.bpk.go.id/Details/104487/permen-pupr-no-29prtm2006-tahun-2006) | | India | 500 mm minimum below natural ground level — a genuinely **fixed national figure**; no numeric frost-depth rule (frost only a qualitative factor in fine sands/silts) | NBC 2016 Part 6 §6.2.2 — [bis.gov.in](https://www.bis.gov.in) | | Japan | Strip footing: embedment ≥240 mm, base-slab ≥150 mm thick, stem ≥300 mm high/≥120 mm thick — a fixed national figure. Regional frost depth (Hokkaidō/Tōhoku) is set by prefectural/municipal ordinance, not national law | [MLIT Notification No. 1347/2000, §一・4](https://www.mlit.go.jp/notice/noticedata/pdf/201703/00006441.pdf) | | Norway | **No fixed depth, frost, width or concrete-grade figure at all** — TEK17 explicitly and entirely defers foundation design to Eurocode 7/2 | [TEK17 §10-2](https://www.dibk.no/regelverk/byggteknisk-forskrift-tek17/10/10-2) | | Sweden | **No fixed depth, frost, width, grade or cover figure at all** — the same full Eurocode deferral as Norway | [BFS 2024:6, Kap 7](https://www.boverket.se/sv/PBL-kunskapsbanken/regler-om-byggande/barformaga-stadga-bestandighet/geokonstruktioner/) | ## Deferring to site investigation is the majority position, not the exception Eight countries — New Zealand, Ireland, France, Germany, Spain, Indonesia, Norway and Sweden — set no fixed centimetre figure for footing depth in their national code at all. Norway and Sweden are the most explicit about it: TEK17 and BFS 2024:6 both defer entirely to Eurocode 7’s site-specific geotechnical design process, with no fallback national number if you skip the investigation. That’s a genuinely different posture from a prescriptive “dig to 450 mm” rule — it puts the engineering judgement on the site conditions themselves rather than a nationwide average that would be wrong for a meaningful share of actual sites. ## India and Japan are the only two with a real fixed number India’s NBC 2016 sets a flat 500 mm minimum below natural ground level, full stop — no soil-type banding, no frost adjustment, just a single national figure. Japan’s approach is more detailed but still genuinely fixed: a strip footing needs at least 240 mm of embedment, a 150 mm base slab, and a stem at least 300 mm high and 120 mm thick, all set by MLIT Notification No. 1347/2000. Notably, even Japan’s regional frost depth (relevant in Hokkaidō and Tōhoku) is set by prefectural or municipal ordinance rather than the national figure — so the embedment number is fixed nationally, but frost protection on top of it still varies by region. ## “Frost depth” is usually a local table, not a national number Even in the countries that do set some kind of footing rule, frost depth specifically tends to drop out to a more local level. The US IRC deliberately leaves its frost-line table blank for each jurisdiction — the code structure assumes your local building department fills in the number that matches your actual climate. Canada’s NBC does something similar: the *depth* figures are national (no limit on rock, 1.2 m on clay), but the *frost* depth behind those figures is set locally. If you’re chasing a frost-line number for your project, your council or building department’s own table is very often the real source, not the national code itself. ## Check your own country’s full footing rules The table above is the headline figures. Each country’s footings hub page covers width, concrete grade, cover and the full clause text: - [Australia — footing sizes & site classification](https://www.chippy.tools/building-codes/au/footings/footing-sizes-site-classification/) - [USA — footing sizes & depth](https://www.chippy.tools/building-codes/us/footings/footing-sizes-and-depth/) - [New Zealand — footing sizes & depth](https://www.chippy.tools/building-codes/nz/footings/footing-sizes-and-depth/) - [UK (England) — footing sizes & depth](https://www.chippy.tools/building-codes/uk/footings/footing-sizes-and-depth/) - [Canada — footing sizes & depth](https://www.chippy.tools/building-codes/ca/footings/footing-sizes-and-depth/) - [Ireland — footing sizes & depth](https://www.chippy.tools/building-codes/ie/footings/footing-sizes-and-depth/) - [France — footing sizes & depth](https://www.chippy.tools/building-codes/fr/footings/footing-sizes-and-depth/) - [Germany — foundation depth & footings](https://www.chippy.tools/building-codes/de/footings/foundation-depth-and-footings/) - [Spain — footing sizes & depth](https://www.chippy.tools/building-codes/es/footings/footing-sizes-and-depth/) - [Indonesia — footing depth & concrete](https://www.chippy.tools/building-codes/id/footings/footing-depth-and-concrete/) - [India — footing sizes & depth](https://www.chippy.tools/building-codes/in/footings/footing-sizes-and-depth/) - [Japan — footing depth & concrete](https://www.chippy.tools/building-codes/jp/footings/footing-depth-and-concrete/) - [Norway — foundation depth & width](https://www.chippy.tools/building-codes/no/footings/foundation-depth-and-width/) - [Sweden — foundation depth & width](https://www.chippy.tools/building-codes/se/footings/foundation-depth-and-width/) ## Get your footing concrete volumes right, whatever depth you end up digging to Whether you’re digging to a fixed 500 mm figure or a depth set by your own site investigation, you still need to know exactly how much concrete to order once the trench is cut. Chippy Tools’ [concrete calculator](https://www.chippy.tools/features/concrete-calculator/) works out volume for footings, post holes and slabs in metric or imperial, so you’re ordering the right amount the first time. ### Skip the manual maths Chippy Tools has professional calculators that handle these calculations for you — offline, on any device. [![Download from the App Store](https://www.chippy.tools/images/download-badges/app-store/en.svg)](https://apps.apple.com/app/apple-store/id1579138717?pt=1325369&ct=chippy.tools&mt=8) [![Download on Google Play](https://www.chippy.tools/images/download-badges/google-play/en.png)](https://play.google.com/store/apps/details?id=tools.chippy&referrer=utm_source%3Dchippy.tools%26utm_medium%3Dwebsite) ## Frequently asked questions Which countries set a genuinely fixed nationwide footing depth? Only two, out of the fourteen we compared. India fixes a flat 500 mm minimum below natural ground level under NBC 2016 Part 6 §6.2.2. Japan fixes a strip-footing embedment of at least 240 mm, with additional fixed figures for base-slab thickness (≥150 mm) and stem height/thickness (≥300 mm/≥120 mm), under MLIT Notification No. 1347/2000. Why do so many countries have no fixed footing depth? Because footing depth genuinely depends on what's underneath the building — soil type, bearing capacity, groundwater, and (in colder climates) frost depth all vary by site and even by region within the same country. Eight of the fourteen countries here — NZ, Ireland, France, Germany, Spain, Indonesia, Norway and Sweden — explicitly hand that decision to a site investigation or Eurocode design process rather than mandating a single number nationally. How is frost depth usually set, if not nationally? Locally, in most of the countries where frost matters. The US model code (IRC) deliberately leaves its frost-depth table blank for each jurisdiction to fill in — Boise's frost line isn't the same as Minneapolis's. Canada's NBC does the same: rock or coarse-grained soil has no depth limit at all, clay/undefined soil needs 1.2 m, but the frost depth behind that figure is set locally, not nationally. Tropical countries like Indonesia skip the concept entirely — there's no frost to design around. What should I do if my country's code sets no fixed footing depth? Get a proper site or geotechnical investigation before you dig. Where a code defers to site conditions instead of a number, that's not an oversight — it's usually because a single national figure would be wrong for a meaningful share of sites. A soil test (or your local building authority's frost-depth table) is the actual source of the number you need, not a rule of thumb. ## Other languages - [es](https://www.chippy.tools/es/articles/footing-depth-and-frost-rules-by-country/index.md)