Your First Year as a General Builder: The Honest Guide

‍‌‌​‌​​​​‌‌‌‌​​​‌‌‌​‌‌​‌‌​​‌‌‌​‌‍# Your first year as a self-employed general builder

Going self-employed as a general builder is different from going out on your own as a single-trade specialist. You're not just doing one thing - you're managing jobs, coordinating other trades, dealing with Building Control, quoting on projects where the scope changes week to week, and carrying more risk than a bloke who turns up, does his trade and goes home.

That's the upside too. General builders have higher earning potential than most single trades because you're selling a complete service, not just labour. But year one has specific traps that catch people out. This guide covers them.

The Improver Reality

Most people coming out of working for someone else aren't ready to run entire jobs solo on day one. That's normal. You're an improver - not a finished builder yet. Own it. Don't take on a full extension when you've never managed subbies, ordered materials to a programme, or dealt with Building Control on your own. Watch how experienced builders run jobs - how they sequence trades, how they handle problems, how they keep customers informed without overpromising. The good ones will teach you if you show willing. This phase lasts months, sometimes a full year. It's not a failure - it's how every decent builder starts.

Don't Be Afraid to Ask

When you're starting out, you will hit things you don't know - a structural detail that doesn't look right, a Building Control question you can't answer, a ground condition you weren't expecting. That's fine. What's not fine is guessing. Pick up the phone. Call a structural engineer. Call Building Control and ask before you pour, not after. Ring a more experienced builder you trust. Nobody worth working with will think less of you for checking. They'll think a lot less of you for cracking on and getting it wrong - especially when it's someone's house.

1. Cards and registrations - what you need

General building has no single mandatory registration scheme. There's no "Gas Safe for builders." But that doesn't mean there's nothing to sort out - and the registrations you do get make a real difference to winning work.

CSCS Blue Skilled Worker card

You need this for any work on larger sites or for main contractors. Even on your own domestic jobs, it shows you've got a recognised qualification and you take health and safety seriously. Apply through CSCS with your NVQ (Level 2 or 3 in a construction discipline) and pass the CITB Health, Safety and Environment test.

Federation of Master Builders (FMB)

Trade association for small and medium builders, including sole traders. Membership is £56.99 + VAT per month (~£68/month), with an extra £13.50 + VAT/month in year one as an inspection fee (or a one-off £162 + VAT annually).

They check: trading history, references, credit, a site inspection of your work quality, insurance and basic paperwork. You get: use of the FMB logo, dispute resolution, contract templates, business advice, and a listing in their "Find a Builder" directory.

For a new general builder, FMB is a credibility badge that says "I'm a serious builder, not a man with a ladder." It also gives you backup if a job gets sticky.

TrustMark

UK Government-endorsed quality scheme. You don't join TrustMark directly - you join through a scheme provider (FMB, NICEIC, NAPIT, NFRC, etc.). They vet your technical competence, trading practices and customer service. You agree to a code of conduct and dispute resolution.

For a domestic builder doing extensions and lofts, TrustMark is worth having if you want ECO/retrofit work or to stand out as the "safe" option to cautious homeowners.

Checkatrade

Monthly membership, price varies by trade and postcode. Basic plans start from about £30 + VAT/month - so a few hundred quid a year for a simple package, more if you buy extra visibility. They check ID, address, insurance, references, sometimes a job check. Then reviews and jobs run through the platform.

Not a quality guarantee - it's a lead machine with a monthly bill. Useful for filling gaps in year one.

For the guide, think of it as: FMB = credibility badge. TrustMark = government-endorsed quality mark. Checkatrade = lead generation.

Building Control knowledge

You don't need a formal qualification in Building Regulations, but you absolutely need to understand the process. Almost all extensions, loft conversions, garage conversions and structural alterations require Building Regulations approval.

What needs approval: new foundations, load-bearing wall removal, new roofs, new floors, new drains, insulation upgrades.

Routes to approval: Full Plans application (drawings checked in advance) or Building Notice (more flexible but riskier, not always allowed on complex jobs). Approval via Local Authority Building Control or a private Approved Inspector.

Core regs you'll touch daily on an extension:

• Part A - Structure: foundations, beams, load-bearing walls, roofs, lateral restraint.
• Part B - Fire safety: escape routes, fire doors, fire protection to beams, smoke alarms.
• Part C - Site prep and moisture: DPCs, drainage, ground conditions.
• Part L - Energy: insulation levels, U-values, thermal bridging, glazing percentages.
• Part F - Ventilation: extract fans, background vents, purge ventilation.
• Part M - Access: thresholds, step-free access where relevant.

Process basics: Don't start without a building control application accepted. Know when inspections are due - foundations, oversite, drainage, steels, insulation, roof, final. Stick to approved drawings and structural engineer's calcs; changes on site must be agreed with designer and building control.

SiteKiln has a full set of Building Regulations guides - read them.

2. Insurance - this is where builders carry more risk

Public liability insurance (PLI)

You need higher limits than most single trades. £2 million is the absolute minimum, but £5 million is strongly recommended for any builder doing structural work - extensions, loft conversions, knock-throughs, work near party walls. £1m is too low for most extensions and lofts now.

What it costs: builder PLI runs higher than single-trade cover because of the structural risk.

• £2m cover: expect roughly £150–£500/year depending on turnover and add-ons.
• £5m cover: more like £400–£1,000/year, especially once you throw in contract works and tools cover.

Simply Business data shows 10% of builders paid £104.70 or less for up to £2m PLI, but that's the very low end. Budget realistically, not optimistically.

Employer's liability insurance

Here's the one that catches new builders out. Before your first labourer's first day, you must:

• Register as an employer with HMRC (PAYE) - do it up to 4 weeks before the first payday.
• Get Employer's Liability insurance - legal requirement from your first employee. Minimum £5 million cover. Typical EL cost for a small firm: £100–£300/year, often bundled with your existing business insurance. HSE can fine you up to £2,500 per day without it.
• Set up a workplace pension - auto-enrolment applies from day one of being an employer.
• Create a basic employment contract - written statement of terms on or before day one.

Check their status properly - employee vs subcontractor - so HMRC doesn't come after you for back tax if you treat an employee as "labour only subby."

What a labourer costs you (2026):

• Outside London: most general labourers ~£100–£160/day depending on experience and region.
• London / SE: more like £150–£220/day, with some going higher on short-notice or specialist work.

On top of that: employer's NI, pension contributions and 5.6 weeks' paid holiday. Budget £120–£180/day all-in for a half-decent labourer in most places, £150–£220+ in London.

When to hire: when you're turning away money or wasting high-value time shifting muck instead of running the job. First six months solo, then a labourer a couple of days a week, then formal hire when the workload proves it.

Contract works insurance (also called contractors' all risks)

This covers the work in progress and materials on site against damage, theft, fire, flood and vandalism. If you're building a £40,000 extension and a storm takes the roof off before it's weathertight, who pays? Without contract works insurance, you do.

Not every builder has this in year one, but for extensions and larger projects it's strongly recommended.

Professional indemnity

If you're providing design input or project management - choosing structural solutions, specifying materials, managing other trades - professional indemnity insurance covers you if your advice or design turns out to be wrong.

3. Pricing - what general builders actually charge in year one

See Guide 14.T11 for detailed general building pricing benchmarks.

Day rate vs quoted - know the difference

Most domestic building work is quoted as a fixed price. Homeowners want to know the total cost of their extension, garage conversion or patio before they commit. A builder who only works on day rate will lose domestic jobs to builders who provide clear quotes.

That said, you'll build your quotes from day rates behind the scenes.

Day rates by region (2026)

These are charge-out rates, not wages. Plant, van, waste, quoting time and dead days all come out of that. London sits 15–25% above national average for construction labour, with the North and rural areas 10–20% below.

Common starter jobs

• Small single-storey rear extensions - typically £30,000–£60,000 total project cost (not your margin - that includes materials, sub-trades, groundworks, etc.). Your labour and management margin on a job like this might be £5,000–£15,000 depending on how much you subcontract.
• Garage conversions - £8,000–£20,000 total. Popular starter project because the structure already exists.
• Patios and hard landscaping - £2,000–£8,000 depending on size and materials.
• Structural alterations (knocking through, RSJs, removing walls) - £2,000–£6,000 per opening depending on structural requirements.
• Refurbishment and renovation - stripping out old bathrooms/kitchens, replastering, new floors, general modernisation. Often quoted room by room.

Margins

As a general builder, your gross margin on a quoted job (after materials and sub-trade costs) should be targeting 20–35%. Below 20% and you're working for wages. Above 35% and you're probably winning fewer quotes than you could be. In year one, expect to be at the lower end while you learn your actual costs.

4. Kit - what you need to start

You're not buying diggers - you'll hire heavy plant. But you still need a decent spread of kit to earn from day one.

Cordless kit

A site-ready builder's cordless setup (SDS, combi, impact, multi-tool, maybe circular saw) lands around £600–£1,000 depending on brand. Multi-tool deals from Makita, DeWalt or Milwaukee are the way in - a 4-piece kit with two 5.0Ah batteries typically runs ~£675, a full 9-piece ~£1,050. Pick one battery platform and stay in it.

Laser level

Mid-range self-levelling line laser: £100–£140. Rotating laser with tripod, staff and detector for setting out extensions: £260–£370. Budget £150–£350 depending on how fancy you go.

Mixer

Belle-type mixer (petrol or 110v) new: typically £350–£600. Many lads buy second-hand, but that's the new price bracket. You'll use it enough to justify buying rather than hiring.

Hand tools

Hammers, chisels, levels, hand saws, shovels, bars, rakes, floats, trowels, nips, clamps, spirit levels (multiple sizes), tape measures, builder's square, chalk line, string line. Plus bricklaying tools if you do your own brickwork. Budget £300–£600 to get properly set up.

Access equipment

Builders' trestles and boards, step ladders, possibly a small scaffold tower. Budget £300–£800 depending on how much you own vs hire. Check ladders are industrial grade (Class 1 or EN 131 Professional).

Heavy plant - hire, don't buy

In year one, hire your mini diggers, dumpers, concrete pumps, telehandlers and skid steers. The cost of owning plant doesn't make sense until you're using it most weeks. Good plant hire relationships are worth developing early.

PPE

Safety boots, hard hat, hi-vis, gloves, eye protection, ear defenders, dust masks (FFP3 for demolition and cutting), signage. Budget £150–£300. Lead by example - if you're running a job with other people on it, you need to be wearing your PPE properly.

Honest starter budget

• If you already have some tools from working for someone else: £2,000–£3,000 to get sensibly kitted.
• Starting light with decent branded gear: £3,000–£5,000 for cordless kit, laser, mixer, hand tools, access and PPE.

Same as every other trade - your day rate has to feed this tool spend.

5. Where the work comes from in year one

Word of mouth - this is everything for builders

More than any other trade, general builders live and die by reputation. A plumber can get away with Checkatrade leads forever. A builder needs referrals. One good extension for one happy customer leads to their neighbour, their colleague, their friend. One bad job - or one job where the customer felt badly communicated with - and the opposite happens.

In year one, every single job is a marketing exercise. Communicate constantly, deliver what you promised, finish on time, clean up properly.

Local reputation and Facebook community groups

Local Facebook groups (village groups, town groups, "recommended tradespeople in [area]" groups) are genuinely powerful for builders. A homeowner posting "Can anyone recommend a builder for a small extension?" with three people tagging you in the comments is worth more than any advertising.

Architect and designer referrals

Once you've done a couple of good projects, introduce yourself to local architects, architectural technicians and interior designers. They get asked "do you know a good builder?" constantly. A builder who communicates well, reads drawings properly and doesn't cause problems is gold dust to an architect.

Checkatrade and similar platforms

Useful for filling gaps in year one. Be selective about which jobs you respond to - extensions and structural work are better leads than "fit a shelf" jobs that don't match your skill set or margins.

6. The big trap - taking on too much too soon

This section doesn't exist in the other first-year guides because it's specific to builders. Single-trade specialists can only really mess up their own trade. A general builder managing a whole project can get into much deeper trouble.

Jobs that need experience

• Extensions with structural steel - you need a structural engineer's design, proper temporary works, and experience managing steel delivery and installation. Getting this wrong can be catastrophic.
• Underpinning - specialist work that should involve a structural engineer and a builder with underpinning experience. This is not a year-one job.
• Party wall issues - the Party Wall etc. Act 1996 applies whenever you're working on or near a shared boundary wall. Failing to serve proper party wall notices can result in injunctions stopping your work and your customer (not you) being sued by their neighbour.
• Basements and waterproofing - specialist work with significant structural and waterproofing risks.

The rule for year one

If a job involves structural engineering, party walls, underpinning, or specialist groundworks and you haven't done that type of job before - don't wing it. Either partner with an experienced builder on the first one, bring in specialist subcontractors, or pass on the job entirely. Your reputation is worth more than one fee.

Know Your Worth

Once you start getting work, there's a temptation to say yes to everything - every extension enquiry, every knock-through, every mate who needs a favour. Don't. Saying yes to every job leads to juggling three sites at once, cutting corners you don't want to cut, and burning out before you've really started. A packed schedule doesn't mean you're making money - if you're running around managing five underpriced jobs, you'd have been better off doing two proper ones at a fair margin. Learn when to say no. Clean work, on time, with no drama gets you recommended. Rushing and overcommitting gets you a reputation you don't want.

What to do next

• Read: Guide 14.T11 - General building pricing benchmarks
• Read: Guide 15.4 - Registering as self-employed with HMRC
• Read: Guide 15.7 - Choosing a business structure (sole trader vs limited)
• Read: Guide 15.11 - Opening a business bank account
• Read: Guide 7.1 - Your rights as a subcontractor on site
• Read: SiteKiln Building Regulations guides - know which jobs need Building Control

Who to contact if you need help

Federation of Master Builders (FMB) - fmb.org.uk - 0330 333 7777 Membership, warranties, contract templates, customer dispute resolution.

TrustMark - trustmark.org.uk Government-endorsed quality scheme for domestic tradespeople.

Local Authority Building Control (LABC) - labc.co.uk Find your local Building Control team and check requirements for your projects.

HMRC Self-Employment helpline - 0300 200 3310 For registering as self-employed and tax questions.

CSCS - cscs.uk.com - 0344 994 4777 For applying for your Skilled Worker card.

Sources (UK)

• Building Act 1985 and Building Regulations 2010 (as amended) - legal framework for building work in England and Wales.
• Party Wall etc. Act 1996 - requirements for work affecting party walls and boundaries.
• Construction (Design and Management) Regulations 2015 (CDM) - health and safety duties, including for domestic clients.
• Employers' Liability (Compulsory Insurance) Act 1969 - employer's liability insurance requirements.
• HMRC Employment Status Manual (ESM) - self-employment status guidance.

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