You are waterproofing a basement wall. You have the materials, the brushes and a free weekend. Then you read on the product data sheet: “Apply in accordance with EN 14967” or “Compliant with DIN 18533.” And you stop. What does that standard actually say? Do you need to follow it? And where on earth do you find it?
Building standards are the invisible backbone of construction. They describe how things should be done — from insulating a wall to wiring a socket to treating timber against rot. Professionals work with them every day. DIYers rarely see them. But if you are doing serious home improvement work, understanding the basics of building standards will save you from costly mistakes, insurance disputes and failed building inspections.
This article explains what building standards are, which ones matter for DIYers, how to access them online and when you actually need to follow them. Practical, straightforward and without the legal jargon.
What are building standards?
Building standards are documents that describe the accepted way of doing something in construction. They define materials, methods, performance levels and testing procedures. They are developed by standards organisations — committees of engineers, manufacturers, researchers and regulators who agree on what constitutes good practice.
The main standards bodies relevant to construction are:
| Organisation | Scope | Examples |
|---|---|---|
| DIN (Deutsches Institut für Normung) | German national standards | DIN 18533, DIN 68800, DIN 4109 |
| CEN (European Committee for Standardization) | European standards (EN) | EN 1991, EN 13162, EN 14967 |
| ISO (International Organization for Standardization) | International standards | ISO 9001, ISO 6946, ISO 13788 |
| BSI (British Standards Institution) | British standards (BS) | BS 5250, BS 8102, BS 7671 |
| ASTM (American Society for Testing and Materials) | Primarily US standards | ASTM C578, ASTM E96 |
A standard is not automatically a law. It is a technical specification that represents current best practice. But in many countries, building regulations reference specific standards, which makes them legally binding in that context. More on that below.
You will often see combined references like “EN ISO 13788” or “BS EN 1991”. This means the standard has been adopted at multiple levels: an ISO standard adopted as a European standard, or a European standard adopted as a British standard. The content is the same — only the prefix changes.
Which standards matter for DIYers?
You do not need to know all 30,000-plus European standards. But there is a manageable set that crops up repeatedly in typical home improvement projects. Here are the most relevant ones, grouped by topic.
Waterproofing and damp proofing
| Standard | Topic | Relevant for |
|---|---|---|
| DIN 18533 | Waterproofing of ground-contact building elements | Basement waterproofing, foundation sealing |
| DIN 18534 | Waterproofing of interior spaces | Bathroom waterproofing, wet rooms |
| BS 8102 | Code of practice for protection of below-ground structures against water | Basement design and waterproofing (UK) |
| EN 14967 | Flexible sheets for waterproofing | Bituminous waterproofing membranes |
Timber protection and construction
| Standard | Topic | Relevant for |
|---|---|---|
| DIN 68800 | Wood preservation (4 parts) | Decking, garden structures, carports, roof timbers |
| EN 335 | Durability of wood — use classes | Choosing the right timber for outdoor use |
| EN 350 | Durability of wood — natural durability ratings | Comparing timber species |
| BS 8417 | Preservation of wood | Timber treatment recommendations (UK) |
Thermal insulation
| Standard | Topic | Relevant for |
|---|---|---|
| DIN 4108 | Thermal protection in buildings | Wall, roof and floor insulation, thermal bridges |
| EN 13162–13171 | Thermal insulation products | Specifications for mineral wool, EPS, XPS, etc. |
| ISO 6946 | Thermal resistance of building components | Calculating U-values |
| BS 5250 | Management of moisture in buildings | Condensation risk, vapour barriers |
Sound insulation
| Standard | Topic | Relevant for |
|---|---|---|
| DIN 4109 | Sound insulation in buildings | Partition walls, floors, windows |
| EN ISO 717 | Rating of sound insulation in buildings | Interpreting sound insulation performance |
| BS 8233 | Guidance on sound insulation for buildings | Acceptable noise levels (UK) |
Electrical installations
| Standard | Topic | Relevant for |
|---|---|---|
| DIN 18015 | Electrical installations in residential buildings | Socket layout, circuit design |
| BS 7671 | Requirements for electrical installations (IET Wiring Regulations) | All electrical work (UK) |
| EN 61439 | Low-voltage switchgear and controlgear assemblies | Consumer units, distribution boards |
Accessibility
| Standard | Topic | Relevant for |
|---|---|---|
| DIN 18040 | Accessible building design | Thresholds, door widths, ramps |
| BS 8300 | Design of an accessible and inclusive built environment | Accessible building design (UK) |
How to access building standards online
Standards are copyrighted documents. You cannot simply download them for free. But there are several ways to access them, from free previews to full paid copies.
1. Official standards stores
Each standards body operates an online shop where you can buy individual standards as PDFs.
DIN Media (dinmedia.de / din.de) — the official publisher for DIN standards. Individual standards cost between 30 and 300 euros depending on length. You can view the table of contents and a preview of the first pages for free.
BSI Shop (knowledge.bsigroup.com) — the official source for BS and BS EN standards. Prices are similar: 30 to 250 pounds for individual standards. BSI offers a preview function and, for some standards, a “tracked changes” version showing what changed from the previous edition.
ISO Store (iso.org/store) — for ISO standards. Prices range from 40 to 200 Swiss francs. The ISO website provides a free preview (scope, table of contents, introduction) for every standard.
CEN (cencenelec.eu) — European standards are typically purchased through national standards bodies (DIN Media in Germany, BSI in the UK, NEN in the Netherlands) rather than directly from CEN.
| Source | What you get for free | Full text cost (typical) |
|---|---|---|
| DIN Media | Title, scope, table of contents, preview pages | 30 – 300 EUR |
| BSI Shop | Title, scope, preview, tracked changes | 30 – 250 GBP |
| ISO Store | Title, scope, table of contents, introduction | 40 – 200 CHF |
| National standards bodies | Varies | Varies |
2. University and public libraries
This is the most cost-effective option for DIYers. Many university libraries in Germany, the UK and the Netherlands have institutional access to standards databases. You can often obtain a library card as an external user and read standards on-screen at the library.
In Germany, many university libraries provide access via DIN Media or the Nautos portal. In the UK, some libraries participate in the BSI Knowledge scheme. Ask your nearest university library about their standards access.
Some larger public libraries also hold collections of frequently used standards, particularly building standards.
3. Standards reading rooms
DIN operates reading rooms (Normenauslegestellen) across Germany where you can consult standards free of charge. BSI previously operated a reading room in London. Check with your national standards body whether a reading room is available near you.
4. Manufacturer documentation
This is the most practical free source for DIYers. Building product manufacturers are required to document compliance with relevant standards. Their product data sheets, installation guides and technical manuals reference the applicable standards and summarise the key requirements.
If you are applying a waterproofing membrane, the manufacturer’s installation guide will tell you how to apply it in accordance with the relevant EN standard. If you are fitting insulation, the product data sheet will reference EN 13162 (for mineral wool) or EN 13163 (for EPS) and state the declared performance values.
In most cases, following the manufacturer’s instructions means you are working in accordance with the standard.
5. Standards commentaries and handbooks
For many widely used standards, publishers produce commentaries — books that explain the standard in plain language, with worked examples and practical guidance. These cost between 30 and 80 euros or pounds and are often more useful than the standard itself.
Examples:
– Commentaries on DIN 68800 (timber protection) for anyone building outdoor timber structures
– Handbooks on BS 7671 (wiring regulations) for anyone involved in electrical work
– Guides to BS 8102 (basement waterproofing) for basement conversion projects
Free vs. paid: what can you access without buying?
| What you need | Available for free? | Where |
|---|---|---|
| Standard title and number | Yes | ISO, DIN, BSI websites |
| Scope and summary | Yes | ISO, DIN, BSI previews |
| Table of contents | Mostly yes | ISO, DIN, BSI previews |
| Full text | No (paid or library) | Standards stores, libraries |
| Practical summaries | Yes | Manufacturer documentation, trade publications |
| Commentaries with worked examples | No (book purchase) | Bookshops, standards stores |
For most DIY projects, the free sources are sufficient. Manufacturer documentation, trade articles and standard previews give you enough to understand what a standard requires. You only need the full text when you are executing a complex project strictly to standard — such as a basement waterproofing to BS 8102 or a timber frame to DIN 68800.
When are building standards mandatory?
This is the question that matters most. The answer depends on your country and the nature of your project.
Standards are not laws — but they carry legal weight
A building standard is, in principle, a voluntary technical specification. It describes best practice but is not automatically a legal requirement. However, there are three situations in which standards become effectively mandatory:
1. Referenced in building regulations.
When national or local building regulations reference a specific standard, compliance with that standard becomes a legal requirement. In England and Wales, the Approved Documents reference numerous BS and EN standards. In Germany, the Landesbauordnungen (state building codes) reference DIN standards. If your project requires building control approval, you will need to comply with the referenced standards.
2. Required by contract.
If you hire a professional or if a building contract specifies compliance with certain standards, those standards become contractually binding. This is less relevant for DIY, but matters if you later sell the property and the buyer’s surveyor checks the work.
3. Evidence of good practice in disputes.
This is the most important point for DIYers. Even when no law requires compliance, standards are treated by courts and insurers as evidence of what constitutes competent work. If a defect leads to a claim, an expert witness will assess whether the work was carried out “in accordance with current standards and good practice.” Compliance with the relevant standard is the strongest defence.
The practical implication
For private DIY projects that do not require building control approval, nobody will inspect your work against a standard. But if something goes wrong — a leak, a structural failure, a fire — the standard becomes the benchmark. Your insurer may reduce or refuse a claim if the work does not meet the relevant standard. A buyer’s surveyor may flag the work as substandard.
Following the relevant standards is not about bureaucracy. It is about doing the job properly and protecting yourself.
Common mistakes DIYers make by ignoring standards
Certain mistakes come up repeatedly when DIYers work without knowledge of the relevant standards:
Basement waterproofing with the wrong system. Many DIYers apply a single coat of bitumen paint and assume the basement is waterproofed. Standards like DIN 18533 and BS 8102 distinguish between different water pressure conditions. A simple coating is insufficient when groundwater pressure is present. The result: ongoing damp, mould and a far more expensive repair than doing it properly the first time.
Timber decking without structural timber protection. Laying timber directly on the ground, using untreated softwood in ground contact, or failing to provide drainage. Standards like DIN 68800 and EN 335 describe how to use timber outdoors so it lasts. Ignoring these principles leads to premature rot — often within three to five years.
Bathroom tiling without proper waterproofing. Tiling a shower enclosure without first applying a tanking membrane or liquid waterproofing. DIN 18534 and BS 5385 describe the waterproofing requirements for wet areas. Skipping this step leads to moisture damage in the structure below, which is invisible until the damage is extensive.
Insulation without addressing condensation risk. Installing insulation without a vapour control layer where one is needed, or placing it on the wrong side. Standards like BS 5250 and DIN 4108 address moisture management in insulated structures. Incorrect insulation can cause condensation within the wall or roof, leading to timber decay and mould.
Electrical work without proper protection. Installing sockets in wet areas without RCD protection, using undersized cables, or failing to notify building control. BS 7671 and DIN 18015 set out the requirements for safe electrical installations. Errors in electrical work are not just a standards issue — they are a safety issue.
Practical tips for DIYers
1. Identify the relevant standards before you start.
For any project beyond basic decorating, spend ten minutes searching for the applicable standards. Search your project type together with “standard” or “DIN” or “BS” online. You will quickly find the relevant standard numbers.
2. Read the manufacturer’s instructions carefully.
Manufacturer documentation is your most accessible guide to standards compliance. If you follow the manufacturer’s installation instructions, you are typically working in accordance with the relevant standard.
3. Use the free previews.
Before buying a standard, check the free preview on the ISO, DIN or BSI website. The scope and table of contents often tell you whether the standard is relevant to your specific project.
4. Visit a library for full texts.
If you need the complete standard, check whether your nearest university library has access. In many cases you can read the standard on-screen at the library for free.
5. Invest in a commentary for complex projects.
For major work like basement waterproofing, roof construction or electrical installations, a standards commentary (a book that explains the standard with practical examples) is a worthwhile investment. It costs 30 to 80 euros or pounds and can prevent errors that cost thousands.
6. Ask at specialist building merchants.
Specialist merchants — not general DIY stores — often have technically trained staff who can advise on which standards apply to your project and which products meet the requirements.
Building standards and insurance
A point many DIYers overlook: your buildings insurance and liability insurance assume that work is carried out competently. If a claim arises from defective workmanship and an assessor finds that the relevant standard was not followed, the insurer may reduce the payout or decline the claim entirely.
This applies particularly to:
– Water damage from inadequate waterproofing (DIN 18533, DIN 18534, BS 8102)
– Fire damage from faulty electrical work (BS 7671, DIN 18015)
– Structural damage from non-compliant timber construction (DIN 68800, EN 335)
You do not need to buy and memorise every standard. But you should understand the core principles of the standards that apply to your project.
Frequently asked questions
Are building standards legally binding for DIYers?
Building standards are voluntary technical specifications in principle. They become binding when referenced in building regulations or building control requirements. Even when not legally required, they serve as the benchmark for competent workmanship in disputes and insurance claims. It is strongly advisable to follow them.
Can I read building standards for free?
The full texts are copyrighted and must be purchased or accessed through a library. However, previews (scope, table of contents, introduction) are available free on the ISO, DIN and BSI websites. Manufacturer documentation and trade publications also summarise key requirements at no cost.
How much does a building standard cost?
Individual standards typically cost between 30 and 300 euros, pounds or Swiss francs depending on length and the issuing body. For DIYers, a standards commentary (a guidebook costing 30 to 80 euros or pounds) is often more useful and better value than buying the standard itself.
What is the difference between DIN, EN, ISO and BS standards?
DIN standards are German national standards. EN standards are European standards developed by CEN. ISO standards are international standards. BS standards are British standards. Many standards are harmonised across levels — so you will see references like “BS EN ISO 6946,” meaning the same standard adopted at British, European and international level. The technical content is identical regardless of the prefix.
Do I need to read the full standard for my DIY project?
In most cases, no. Manufacturer installation guides, trade articles and standard previews give you enough practical guidance. You should consider reading the full text only for complex projects where strict compliance matters — such as basement waterproofing, structural timber work or electrical installations.
What happens if I do not follow a building standard?
For private projects without building control involvement, there is no immediate enforcement. But if a defect causes damage, your insurer or a surveyor will assess the work against the relevant standard. Non-compliance weakens your position in any dispute and may result in a reduced or declined insurance claim.
Where do I find out which standard applies to my project?
Search your project type together with “standard,” “DIN,” “BS” or “EN” online. Manufacturer product data sheets also reference the applicable standards. Specialist building merchants can advise as well.
Are older standards still valid?
Standards are regularly revised. Always check the current edition. On the DIN, BSI and ISO websites, you can see whether a standard is current, withdrawn or replaced. When buying a standard, ensure you are purchasing the latest version.
Conclusion
Building standards are not red tape for professionals only. They describe how construction work should be done — and that applies whether the work is done by a contractor or by you in your own home. As a DIYer, you do not need to buy and study every standard. But you should know which standards apply to your project and what they fundamentally require.
The key steps:
- Identify the relevant standards before starting any significant project
- Read manufacturer installation instructions — they reflect the applicable standards
- Use free previews on standards body websites to check relevance
- Visit a university library for free access to full texts when needed
- Invest in a standards commentary for complex projects
Understanding the basics of building standards means you work more safely, avoid expensive errors and stand on solid ground if anything goes wrong.
Check out our DIY plans at fredsdiyplans.com for more home improvement projects.