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Project Overhead & Management

Understanding the costs of running a construction business. Overhead isn't waste—it's essential to professional service delivery.

What Is Project Overhead?

Overhead costs are the business expenses required to operate a construction company and deliver professional service. These include rent, insurance, management, planning, and profit. Typical overhead is 20-35% of labour cost, though this varies by company size and type.

Business Overhead Costs

Rent & Facilities

Office/workshop rent: £1,000-5,000+ per month

Utilities (electricity, water, heating): £200-800 per month

Facility maintenance: £300-1,000 per month

Parking/storage for vehicles & equipment: £200-1,000 per month

A 10-person construction company typically has £3,000-8,000/month in facility costs.

Insurance

Public liability insurance: £500-2,000 per year

Employers' liability insurance: £600-2,000 per year

Professional indemnity insurance: £800-3,000 per year

Vehicle insurance (multiple vehicles): £2,000-8,000 per year

Tools & equipment insurance: £500-2,000 per year

Total insurance: typically £1,500-3,000 per month for established company.

Administrative & Management

Office staff salaries: £2,000-6,000 per month (if employed)

Accountant/bookkeeper fees: £200-600 per month

Legal fees (contracts, disputes): £100-400 per month (average)

Business software subscriptions: £100-300 per month

Phone & internet: £50-150 per month

Office supplies: £100-300 per month

Small companies often subcontract these. Larger companies employ staff.

Vehicles & Transport

Vehicle lease/finance: £300-800 per vehicle per month

Fuel costs: £200-600 per vehicle per month

Maintenance & repairs: £100-400 per vehicle per month

Vehicle tax/MOT: £50-100 per vehicle per month

A company with 5 vehicles: £3,000-8,000/month in transport costs.

Marketing & Business Development

Website & SEO: £200-500 per month

Local advertising: £200-800 per month

Google Ads: £300-1,000 per month

Printed materials (business cards, flyers): £100-300 per month

Companies spend 5-10% of turnover on marketing/business development.

Training & Compliance

Staff training (health & safety, skills): £200-600 per year per employee

Health & safety compliance: £300-800 per year

Certifications/memberships: £200-500 per year

PPE (hard hats, vests, boots): £500-2,000 per year for team

Project-Specific Management Costs

Site Supervision & Coordination

Project manager/supervisor time: £50-150/hour

Daily site visits/coordination: Usually 2-4 hours per day on larger projects

Communication with client, trades, suppliers: 1-2 hours per day typical

A 5-day project with supervisor: 3 hours/day × £80/hour × 5 days = £1,200 in management time alone.

Non-Billable Time

Site quotes/consultations: 1-3 hours (often unpaid)

Tender/proposal preparation: 2-4 hours (often unpaid, won't be used)

Site setup/cleanup (management): 1-2 hours before/after work

Paperwork/documentation: 30 minutes per day typical

Travel time between sites: 30 minutes to 2 hours depending on location

For every billable hour, contractors often spend 0.5-1 hour on non-billable work.

Profit Margin

Is Profit Margin "Extra Charge"?

No. Profit margin (typically 15-20% for quality contractors) is essential for business viability. It covers:

  • Business growth and investment in better equipment
  • Cash flow—contractors have to buy materials before invoicing you
  • Bad debts—some customers don't pay
  • Slow periods when there's no billable work
  • Paying staff holidays and sick leave
  • Reinvestment in training and certification

Profit Tier Expectations

10-12% profit: Budget contractors, high-volume, lower service level

15-20% profit: Standard professional contractors, sustainable business model

20-30% profit: Premium/specialist contractors, high-end projects, comprehensive service

Over 30% profit: Either taking on excessive risk or potentially overpricing

Real Cost Breakdown

10-Person Construction Company - Monthly Costs

Office rent & facilities:£5,000
Insurance (vehicles, liability, etc.):£2,500
Office admin staff (1 person):£2,500
Professional services (accountant, lawyer):£800
Vehicle costs (5 vehicles):£6,000
Marketing & business development:£2,000
Training, compliance, PPE:£1,000
Tools & equipment maintenance:£1,200
Total Monthly Overhead:£21,000

This overhead must be spread across billable hours. If company works 800 billable hours/month (10 people × 40 hours × 2 weeks), overhead is £26/hour minimum.

Why Overhead Varies

  • Company size: Solo operator has lower overhead than 20-person firm
  • Location: London office rent: £3,000-5,000. Northern city: £1,000-2,000
  • Service level: Premium companies with better equipment/training spend more on overhead
  • Specialisation: Specialist work (listed buildings, heritage) has higher overhead
  • Business model: Companies with office staff have higher overhead than solo traders

Red Flags in Overhead Pricing

  • Quote with no overhead/management mentioned: Unrealistic—overhead always exists
  • Excessive overhead charges: Over 30% of labour cost is high (unless premium service)
  • Vague "management fee": Should be itemised or as percentage clearly stated
  • "No overhead" promise: Impossible. Either deliberately misleading or unsustainable pricing

Key Takeaways

  • Overhead costs are real and substantial—£15,000-30,000+ per month for professional firms
  • Professional service (reliable, insured, trained) requires overhead investment
  • Profit margin 15-20% is normal and healthy for sustainable business
  • Extremely cheap contractors are either taking unsustainable risk or cutting corners