Quick Answer
In 2026, ten jobs you should never DIY in the UK include: any gas work, full electrical rewires, structural wall removal, asbestos removal, roof replacement, boiler installation, adding new electrical circuits, underpinning, skylight installation, and oil tank installation. These carry legal, financial, and life-safety consequences if done incorrectly.
The rise of YouTube tutorials and DIY culture in 2026 has made home improvement seem more accessible than ever. Most of the time, that's a good thing — there is no reason to pay a professional to paint a room or fit a shelf. But some jobs carry legal restrictions, safety risks, or insurance implications that make DIY genuinely dangerous. This guide covers the ten jobs where you must hire a qualified professional.
In this guide
1. Gas Work of Any Kind
Why you must not DIY this
Gas leaks cause explosions and carbon monoxide poisoning — both can be fatal. Even seemingly minor jobs like repositioning a gas hob or adding a new gas pipe carry serious risk if done incorrectly.
Legal requirements
All gas work in the UK must be carried out by a Gas Safe registered engineer. It is a criminal offence under the Gas Safety (Installation and Use) Regulations 1998 to carry out gas work without registration. Your home insurance will be invalidated.
Who to hire: A Gas Safe registered engineer. You can verify registration at the official Gas Safe Register website or check our guide on what to look for in a Gas Safe engineer.
2. Full Electrical Rewire
Why you must not DIY this
A full rewire involves replacing all the wiring in your home. Incorrectly installed wiring is a leading cause of house fires. It also requires proper testing and certification to confirm the installation is safe.
Legal requirements
Full rewires fall under Part P of the Building Regulations. The work must be notified to your local council (via a registered electrician who self-certifies, or via a building inspector). Unregistered electrical work makes your home unmortgageable and uninsurable.
Who to hire: A Part P registered electrician. For guidance on finding one, see our article on how to find a trustworthy electrician.
3. Structural Wall Removal
Why you must not DIY this
Load-bearing walls hold up the structure of your home. Remove one incorrectly and you risk partial or total collapse. This is not a theoretical risk — it happens every year in the UK.
Legal requirements
Removing a load-bearing wall requires Building Regulations approval and a structural engineer's calculation to confirm the correct size of RSJ (steel beam) required. Failure to get approval means the work will need to be reversed or you cannot sell the property.
Who to hire: A structural engineer plus a qualified builder for the physical work.
4. Asbestos Removal
Why you must not DIY this
Asbestos fibres cause mesothelioma (a fatal cancer) and asbestosis. Properties built before 2000 may contain asbestos in floor tiles, ceiling tiles, artex, pipe lagging, and roofing. You cannot see or smell it.
Legal requirements
Only licensed contractors can legally remove certain categories of asbestos-containing materials (ACMs) under the Control of Asbestos Regulations 2012. Even non-licensed work has strict requirements. DIY removal is illegal and dangerous.
Who to hire: A licensed asbestos removal contractor. Get a survey first from an independent asbestos surveyor to identify what you are dealing with.
5. Roof Replacement
Why you must not DIY this
Working at height is one of the leading causes of fatal injuries in the UK. Beyond safety, an improperly replaced roof will leak, cause structural timber rot, and void your home insurance if it fails within a reasonable period.
Legal requirements
Replacing an entire roof requires Building Regulations sign-off if the structure changes. Even like-for-like replacement has thermal performance requirements under current regulations. Roofers also need to follow Working at Height Regulations.
Who to hire: A qualified roofer with specialist public liability insurance and a warranty on their work. For more guidance, see our article on how to vet a roofer.
6. Boiler Installation
Why you must not DIY this
Boilers burn fuel (gas, oil, LPG) and produce flue gases including carbon monoxide. A poorly installed boiler can leak CO, which is odourless and kills quickly. Poorly connected condensate pipes and pressure issues are also serious risks.
Legal requirements
Boiler installation is gas work — it must be done by a Gas Safe registered engineer. The installation must also comply with Building Regulations Part J (combustion appliances) and Part L (energy efficiency). The engineer issues a Building Regulations compliance certificate.
Who to hire: A Gas Safe registered heating engineer. Always request the compliance certificate upon completion.
7. Adding New Electrical Circuits (Part P Work)
Why you must not DIY this
New circuits must be correctly sized, protected with the right fuse or MCB, and earthed properly. Errors cause fires and electric shocks. Circuits in bathrooms are particularly dangerous because of the combination of water and electricity.
Legal requirements
Adding a new circuit is notifiable work under Part P of the Building Regulations. It must be certified by a registered electrician (NICEIC, NAPIT, or similar) or notified to your local authority building control. Uncertified work will appear on property searches and can block a house sale.
Who to hire: A Part P registered electrician. Check our guide on how to find a trustworthy electrician.
8. Underpinning
Why you must not DIY this
Underpinning is used to stabilise or deepen existing foundations — usually when subsidence is detected. Incorrectly done, it can make the structural problem significantly worse, costing tens of thousands of pounds to correct.
Legal requirements
Underpinning is notifiable work under Building Regulations and requires structural engineer sign-off at every stage. The work is also relevant to mortgage lenders and insurers — always notify both before and after work.
Who to hire: A specialist structural repair contractor, always working from a structural engineer's specification.
9. Skylight (Rooflight) Installation
Why you must not DIY this
Installing a skylight involves cutting through the roof structure, repositioning or adding rafters, and ensuring the new opening is weathertight and structurally sound. Errors cause leaks, rot, and structural weakness — all of which are expensive to fix.
Legal requirements
Adding a rooflight typically requires Building Regulations approval (thermal performance, structural changes) and potentially planning permission depending on the roof type and location. Listed buildings and conservation areas have additional restrictions.
Who to hire: A qualified roofer with skylight installation experience, working from a structural engineer's drawing if rafters need to be cut.
10. Oil Tank Installation
Why you must not DIY this
Oil tanks store large quantities of combustible fuel. Poorly installed tanks leak heating oil into the ground — a single spill can cost £10,000–£100,000+ to remediate, and the homeowner is legally liable for the environmental clean-up.
Legal requirements
Oil tank installation must comply with Building Regulations Part J and the Oil Firing Technical Association (OFTEC) standards. The installer must be OFTEC registered. Local planning permission may be required depending on tank size and location.
Who to hire: An OFTEC registered technician. Ask for their OFTEC registration number and verify it before work starts.
Not sure if your job needs a professional?
Check our guide on how to check if a tradesperson is qualified in the UK — or post your job on GetQuickHelp and let qualified local tradespeople tell you what's needed and what it will cost.
Frequently Asked Questions
Can I legally do my own home repairs in the UK?+
Yes — most repairs and maintenance do not require professional certification. You can paint, tile, fit shelves, replace like-for-like fixtures, and carry out many general DIY tasks. The restrictions apply to regulated work: anything involving gas (must be Gas Safe registered), notifiable electrical work (Part P), and certain structural or hazardous material activities. Always check if your planned work is notifiable before starting.
What happens if I do gas or electrical work myself without certification?+
For gas work, it is a criminal offence under the Gas Safety (Installation and Use) Regulations 1998. You could face an unlimited fine or prosecution. For electrical work, uncertified work under Part P makes it illegal to sell or mortgage the property without retrospective sign-off — which is expensive and not always possible.
Will my home insurance be invalidated if I do this work myself?+
Almost certainly for regulated work. Most home insurance policies contain a clause that voids cover for damage caused by work not carried out by qualified professionals. If a fire results from DIY electrical work, your insurer can refuse to pay. Even for non-regulated work, if the damage is caused by your own DIY error, many policies treat this as 'wear and tear' or wilful neglect rather than an insurable event.
How do I check if a tradesperson is qualified for the work I need?+
For gas work, check the Gas Safe Register (gassaferegister.co.uk). For electrical work, check NICEIC or NAPIT registers. For asbestos, check the HSE's licensed asbestos contractor list. For general builders, check FMB or TrustMark. Our dedicated guide covers
Is it worth getting a survey before starting major work?+
Almost always yes. Before any structural work, a structural engineer's survey could save you thousands by revealing what you're actually dealing with. Before renovating older properties, a full building survey may reveal asbestos, hidden water damage, or structural issues that change the entire scope of the project.
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