U-Value Requirements by Country
Check U-value limits for walls, roofs, floors, windows and doors. Compare building regulations by country and verify your design against official sources.
Browse regulations
Explore the requirements without a compliance check. Open a row for conditions, exceptions, sources and versions.
| Country | Regulation | Building type | Element | Requirement | Effective from | Status | Verified | Data quality |
|---|
National regulations may use different methodologies, climate assumptions and compliance frameworks.
A lower limit does not mean a stricter or more efficient building code. Countries calculate U-values differently, some set whole-building limits where element values are only reference values, and climates differ. Use this table to read each country's own rule, not to rank countries.
Compare countries
Select up to six countries. Every country is checked with the same building, element and date.
| Country | Requirement | Regulation | Conditions | Effective date | Source | Data quality | Your U-value |
|---|
Select at least one country to compare.
Country coverage
Available means that on the date shown verified limits for new buildings are in force for walls, roofs, floors, windows and external doors, for residential and at least one non-residential building type (or verified whole-building limits for both, where a country sets only those). Partial means some requirements are in force but part of this is missing, not verified yet or limited to some building types. Coverage can change on a future date when a regulation expires or a new one starts.
Missing a country? Request it.
| Country | Coverage today | Approach | Requirements | Last reviewed | Scope |
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How to check U-value requirements
- Choose the country. A region or climate zone field appears only when that country's rules depend on it.
- Pick the building status, the building type and the element, and enter the design indoor temperature.
- Read the applicable requirement, its regulation and version, the conditions it depends on and the official source.
- Optionally enter your calculated U-value for a PASS or FAIL, and a design target to check your own, stricter goal separately.
- Use Browse to explore all records, Compare to read several countries side by side and Countries to see what is covered.
How a requirement is chosen
A limit is never taken from the country and the element alone. Each requirement is a record with the regulation, its validity dates and the conditions it applies under, and a rules engine picks the record that applies to your case:
- Validity. Only requirements in force on the assessment date count. Expired versions stay in the database for historical checks, upcoming ones are listed separately and drafts are never applied.
- Scope. The record must cover the region or climate zone, the building status, the building type and the element. A general roof rule also covers flat and pitched roofs; a window rule never covers a roof window.
- Conditions. Indoor temperature bands, adjacent space and construction type must match.
- Most specific wins. A regional rule beats a national one, a rule for one building type beats a rule for all types, and a rule for the exact element beats the general one.
- No guessing. If missing information could change the answer, the database asks for it. If equally specific rules give different values, it lists them instead of choosing.
Regulatory requirement and design target
The regulatory requirement is the legal minimum. The design target is an optional, usually more ambitious value you choose. Both are shown as separate rows and checked independently, so a construction can pass the regulation and still miss your target.
PASS U_calc ≤ U_max
Margin U_max − U_calc [W/m²K]
Better than req. (U_max − U_calc) / U_max × 100 [%]
FAIL exceeded by U_calc − U_max, (U_calc − U_max) / U_max × 100 % above
Close to limit PASS with 5 % or less to spare
For a minimum R-value the comparison is mirrored. A calculated U-value is never converted into an R-value, because regulations define thermal resistance in different ways. When no requirement exists, a custom target can be checked instead and is labelled as a custom design target.
Data quality and sources
Every record links to its official source and carries a short verbatim quote, the location in the document, the language, the verification date and a confidence level. Each value has one of five data quality states: Verified, Needs review (with the reason), Partial data, Outdated (verified more than 365 days ago) and Unknown. Secondary sources are stored only as supporting material and are marked as such.
Why limits are not directly comparable
National regulations may use different methodologies, climate assumptions and compliance frameworks. One country's wall U-value may include thermal bridges and fixings, another's may not. Ground floors can include heat transfer through the ground. Windows may be rated as whole units. US values are U-factors in inch-pound units converted to SI. Several countries assess new buildings against a whole-building energy limit or a reference building, so their element values are reference or route values rather than hard limits, and the database shows them as information only.
Limitations
The database covers national rules for the listed countries only, as described on the Countries tab. Regional and local amendments, funding standards and project-specific approvals are not included. Transitional provisions often tie the applicable version to the permit application date rather than the date of the check, so read the exceptions of each record.
Frequently asked questions
How does the database choose the applicable U-value requirement?
It filters the requirements of the chosen country by assessment date, region or climate zone, building status, building type, element and conditions such as the indoor temperature. When several rules match, the most specific one applies, in that order of priority. If a rule that depends on missing information could change the answer, the database asks for that information, and if two equally specific rules give different values it shows both instead of picking one.
What is the difference between the regulatory requirement and the design target?
The regulatory requirement is the legal minimum from the regulation, for example a maximum U-value of 0.20 W/m²K. The design target is your own, usually stricter value, for example 0.15 W/m²K. They are checked separately: a wall with U = 0.17 W/m²K passes the regulation and fails that design target. A design target never changes the regulatory result.
What does "Needs review" mean?
Every value carries a data quality status: Verified, Needs review, Partial data, Outdated or Unknown. Verified means the value was checked against the official text and reviewed within the last 365 days. Needs review means it has not been confirmed yet, and the record states why. Unverified values are always labelled and are never presented as official.
Can I compare U-value limits between countries?
Only with care. National regulations may use different methodologies, climate assumptions and compliance frameworks. Some include thermal bridges or heat transfer through the ground in the U-value and some do not, and several countries assess the whole building, so their element values are reference values rather than limits. A lower number does not mean a stricter building code.
What happens when no requirement is found?
The database shows "No verified requirement available" and explains why: the country, building status or element is not covered, or no rule is in force on the assessment date. It never invents a limit. You can enter a custom target to check your value, and that result is marked as a custom design target, not as a regulatory requirement.
Which date does the check use?
The assessment date, which is today unless you change it. Regulations change over time, so an earlier date shows the rules that applied then, and upcoming changes are listed separately. In practice the date that counts is often the date of the permit application, and transitional rules can let a project keep earlier values, so read the exceptions and the official text.
Is the result legally binding?
No. It is engineering guidance built from official sources, with a verbatim quote, the location in the document and a verification date for every value. The official text always prevails, and local amendments or project-specific approvals can apply.