Plant Insurance for Compressors & Generators: Construction & Engineering Cover Explained
Running compressors and generators on a construction or engineering site is non-negotiable. They keep tools running, cabins powered, dewatering pumps moving, and deadlines on track. But they’re also high-value, high-risk bits of kit—often moved between sites, left in exposed locations, and operated under pressure.
Plant insurance (often called contractors’ plant insurance) is designed to protect your compressors and generators against the real-world risks that standard business insurance or vehicle policies usually won’t cover. Below is a practical, UK-focused guide to what plant insurance is, what it covers, what it doesn’t, and how to buy the right policy for your setup.
What is plant insurance (and why it matters for compressors and generators)?
Plant insurance is a specialist policy that covers construction and engineering equipment—whether you own it, hire it in, or lease it. For compressors and generators, it typically covers:
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Theft (including from site, yard, or vehicle)
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Accidental damage (drops, impacts, mishandling)
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Fire and explosion
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Flood and storm damage
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Vandalism and malicious damage
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Damage during transit (depending on policy)
Why it matters: compressors and generators are often classed as “high-theft” items, especially portable units and towable sets. They’re also frequently used in harsh conditions where damage is more likely. A single loss can wipe out profit on a job—particularly if you’re also hit with downtime, hire replacement costs, and contractual penalties.
Who needs plant insurance for compressors and generators?
Plant insurance is relevant if you’re any of the following:
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Groundworkers and civil engineering contractors
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M&E contractors and site services firms
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Plant and tool hire companies
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Construction companies running multiple sites
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Utilities contractors (water, power, telecoms)
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Rail and highways contractors
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Demolition and remediation firms
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Facilities and maintenance teams using generators for temporary power
It’s also worth considering if you’re a smaller contractor who owns just one compressor and one generator. These items are expensive to replace, easy to steal, and essential to keep work moving.
What types of compressors and generators can be covered?
Most insurers can cover a wide range of plant, including:
Compressors
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Portable diesel compressors
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Electric compressors
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Towable compressors
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Screw compressors
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High-pressure compressors for specialist engineering
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Site air compressors used for breakers, drills, blasting, and pneumatic tools
Generators
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Portable generators
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Towable generator sets
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Silent/boxed generators
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Diesel generators for site power
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Three-phase generators
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Standby generators used for critical operations
Policies can usually be arranged for single items, lists of specified items, or “any one item” cover for fluctuating plant schedules.
Key covers to look for (and what they actually mean)
Plant insurance isn’t one-size-fits-all. Here are the core cover sections you’ll see and what they mean in practice.
1) Own plant cover (contractors’ plant)
This covers compressors and generators you own against loss or damage. It’s typically written on an “all risks” basis—meaning it covers most sudden and unforeseen events unless excluded.
What to check:
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Are items covered on-site, in transit, and in storage?
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Is theft covered from unattended sites?
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Are there security conditions (locks, chains, trackers, compound requirements)?
2) Hired-in plant cover
If you hire compressors or generators from a plant hire company, you’re often responsible for them under the hire agreement. Hired-in plant cover protects you if the hired equipment is stolen or damaged.
What to check:
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Does the policy cover the hire company’s “loss damage waiver” requirements?
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Is the hire period covered automatically or do you need to notify each hire?
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Are you covered for continuing hire charges while the item is being repaired?
3) Plant hire out cover (for hire companies)
If you hire compressors and generators out to customers, you need a policy that covers equipment while on hire.
What to check:
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Does it cover theft by hirers or “theft by deception”?
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Are there strict hire contract conditions you must follow?
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Are you covered for recovery costs if equipment goes missing?
4) Transit cover
Many losses happen between sites—loading, unloading, reversing into gates, straps failing, or theft from vehicles.
What to check:
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Is cover included automatically or as an extension?
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Are items covered while left in a vehicle overnight?
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Are there requirements for locked vans, alarms, or secure compounds?
5) Breakdown and inspection (optional)
Plant insurance is mainly for external events (theft, accidental damage). Mechanical or electrical breakdown can be excluded unless you add a breakdown section.
This can be valuable for:
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Generator alternator failures
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Control panel faults
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Compressor motor failures nWhat to check:
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Is wear and tear excluded?
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Are servicing and maintenance records required?
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Is there cover for sudden breakdown only?
6) Loss of hire / business interruption (optional)
If a generator is stolen and you can’t supply power to a site, you may lose income or face penalties.
What to check:
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Does it cover lost revenue, additional hire costs, or both?
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What is the indemnity period (e.g., 4, 8, 12 weeks)?
Common exclusions and “gotchas”
This is where many claims fall apart. Typical exclusions include:
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Wear and tear, gradual deterioration, corrosion
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Mechanical or electrical breakdown (unless added)
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Theft from an unattended site if security conditions weren’t met
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Theft from an unlocked vehicle or where keys were left accessible
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Unexplained disappearance (no evidence of forced entry)
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Damage due to incorrect use or lack of maintenance
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Damage to tyres (relevant for towable sets) unless accompanying other damage
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Consequential loss (unless you add loss of hire/business interruption)
The practical point: insurers want to see that reasonable security and risk management was in place. If your compressor was left loose in an open yard with no chain, no compound, and no CCTV, you’re more exposed.
How insurers rate risk for compressors and generators
Premiums and terms are influenced by:
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Value and type of equipment (portable vs fixed, towable vs static)
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Number of sites and locations (higher movement = higher risk)
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Theft history (your claims record and local crime rates)
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Storage arrangements (locked yard, compound, CCTV, lighting)
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Security measures (immobilisers, hitch locks, chains, trackers, key control)
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Operator controls (training, sign-out logs, inspections)
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Business type (civil engineering, utilities, rail, hire company)
If you want better pricing, the fastest wins are usually security and documentation.
Security best practices that can reduce claims issues
Even if you’re not trying to “tick boxes,” these measures can help you avoid disputes at claim time:
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Store towable generators/compressors in a locked compound or secure yard
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Use hitch locks, wheel clamps, and heavy-duty chains anchored to fixed points
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Fit GPS trackers on higher-value items
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Keep keys locked away and maintain a key log
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Use asset marking (forensic marking, engraving)
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Photograph equipment and keep serial numbers recorded
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Use site checklists for end-of-day security
Insurers may specify minimum security requirements—especially for theft cover.
How to set the right sums insured
Underinsurance is a common issue. If you insure a generator for £10,000 but it costs £16,000 to replace like-for-like (including delivery and setup), you may receive a reduced payout.
Best practice:
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Insure on a replacement-as-new basis where possible
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Include delivery costs, installation, and ancillary kit (cables, distribution boards if relevant)
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Review values annually (or whenever you buy new plant)
If you have many items, consider:
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A specified items schedule for high-value equipment
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An “any one item” limit for smaller, frequently changing items
Plant insurance vs other policies: what’s the difference?
It’s easy to assume other policies will cover your kit. Often they won’t.
Commercial vehicle insurance
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Covers the vehicle, not the plant being carried (unless specifically endorsed)
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Theft from vehicles can be restricted
Public liability and employers’ liability
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Covers injury and property damage to third parties/employees
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Does not cover your own equipment theft/damage
Contract works insurance
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Covers the works in progress (materials, partially completed works)
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Not always designed for standalone plant items
Plant insurance is the policy designed specifically for your compressors and generators.
Claims examples (real-world scenarios)
Here are common claim situations where plant insurance can be the difference between a bad day and a business-threatening loss:
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Towable generator stolen overnight from a site compound after the padlock was cut.
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Compressor damaged during loading when a telehandler slips and the unit is dropped.
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Flooded generator after heavy rain and poor site drainage causes water ingress.
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Vandalism where a generator’s control panel is smashed and wiring is ripped out.
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Fire damage in a storage container affecting multiple pieces of plant.
Each of these can be covered—assuming the policy terms and security conditions were met.
What information you’ll need to get a quote
To get accurate terms quickly, have this ready:
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Business details (trade, turnover, years trading)
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Claims history (typically 3–5 years)
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Plant list: make/model, year, serial numbers, values
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Storage details: yard/compound, postcode, CCTV, alarms, lighting
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Use details: number of sites, typical regions, overnight storage arrangements
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Security: locks, chains, trackers, key control
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Hired-in requirements (if applicable)
If you don’t have a full plant list, you can still start with your top 5–10 highest value items.
Choosing the right policy structure
There are three common ways to set up cover:
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Single item cover: good for one generator or one compressor.
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Specified plant schedule: best for multiple high-value items.
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Floating plant / any one item limit: useful if your equipment changes frequently.
For many construction and engineering firms, a hybrid approach works well: schedule the big-ticket items and float the rest.
Tips to keep premiums sensible without cutting corners
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Increase your excess (only if you can absorb smaller losses)
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Improve security (often more effective than negotiating price)
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Keep a clean claims record by managing small losses internally
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Maintain servicing records (helps with breakdown disputes)
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Avoid underinsuring—cheap premiums can become expensive at claim time
FAQs: Plant insurance for compressors and generators
1) Is plant insurance legally required?
No, plant insurance isn’t legally required in the UK. But it’s often contractually required, and it’s a practical necessity if you rely on expensive equipment.
2) Does plant insurance cover theft from site?
Usually yes, but theft cover often depends on meeting security conditions (locked compound, chains, evidence of forced entry, etc.).
3) Are compressors and generators covered while in transit?
Often, but not always automatically. Check whether transit is included and whether overnight vehicle theft is covered.
4) Does it cover hired-in generators and compressors?
Yes, if you add hired-in plant cover. Without it, you could be paying out of pocket under the hire agreement.
5) Does plant insurance cover mechanical breakdown?
Not typically. Mechanical/electrical breakdown is often excluded unless you add a breakdown extension.
6) What’s the difference between “all risks” and “named perils”?
“All risks” covers most sudden, unforeseen events unless excluded. “Named perils” only covers the specific events listed (e.g., fire, theft). All risks is usually broader.
7) Do I need to list each item?
Not always. Some policies allow a blanket sum insured with an “any one item” limit. High-value items are often best listed.
8) What if my generator is stolen but there’s no sign of forced entry?
That can be difficult. Many policies exclude “unexplained disappearance.” Good site security and documentation help.
9) Can I insure older compressors and generators?
Often yes, but terms may vary. Insurers may apply higher excesses or restrict breakdown cover for older equipment.
10) Will the policy cover accessories and cables?
Sometimes, but you may need to specify them or include them in the sums insured. Ask for confirmation.
11) Does plant insurance cover damage caused by my employees?
Accidental damage caused by employees is often covered, but deliberate damage is not.
12) What’s a typical excess?
It varies by insurer, item value, and theft risk. Theft excesses can be higher than accidental damage excesses.
13) Can I cover plant stored at home?
Sometimes, but insurers may apply stricter security requirements. It’s best to disclose home storage.
14) What if I work across multiple sites in the UK?
That’s common. Policies can cover plant anywhere in the UK, but you must confirm territorial limits.
15) Does plant insurance cover loss of income?
Not by default. You’ll need loss of hire or business interruption extensions.
Final thoughts: protect the kit that protects your deadlines
Compressors and generators are the heartbeat of many construction and engineering projects. Plant insurance helps you protect that investment, keep jobs moving, and avoid the kind of unexpected costs that can derail cashflow.
If you’re not sure what you need, start with two questions:
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What would it cost to replace your key compressor/generator tomorrow?
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Could you keep working next week if it disappeared tonight?
If the answer makes you uncomfortable, it’s time to put proper plant cover in place.
Need plant insurance for compressors and generators?Insure24 can help you arrange tailored contractors’ plant insurance, hired-in plant cover, and construction & engineering insurance—built around your equipment, your sites, and your contracts. Call 0330 127 2333 or request a quote at insure24.co.uk.

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