The UK buy-to-let (BTL) market has changed dramatically over the last decade. Property values have risen sharply, build costs have surged, regulation has tightened, and landlord margins are under pressure from every direction.
Yet one risk continues to sit quietly in the background—underinsurance.
It’s not headline-grabbing. It doesn’t affect loan-to-value calculations. And it rarely shows up until the worst possible moment: a major claim.
For mortgage brokers working in the BTL space, underinsurance is no longer just an insurance issue. It’s a client risk, a reputational risk, and an advice gap that deserves attention.
What Underinsurance Really Looks Like in BTL
Underinsurance isn’t about having no insurance. In fact, most landlords believe they are adequately covered.
The reality is more uncomfortable.
Common examples we see across the BTL market include:
- Rebuild sums insured based on outdated valuations (often years old)
- Policies still aligned to purchase price, not rebuild cost
- No allowance for professional fees, debris removal, or compliance upgrades
- Inflation eroding cover while sums insured remain static
- Portfolio landlords using blanket figures across multiple properties
With construction costs rising significantly over recent years, a property insured for £300,000 may realistically require £450,000+ to rebuild today. That gap is where underinsurance lives.
The Pitfalls: Why Underinsurance Hurts Landlords Most
Underinsurance doesn’t just reduce claim payouts—it can invalidate financial planning altogether.
Key consequences include:
1. Average Clauses at Claim Stage
If a property is insured for 70% of its true rebuild cost, insurers may only pay 70% of the claim, even for partial losses.
2. Breach of Mortgage Conditions
Most BTL mortgage offers require adequate buildings insurance. Underinsurance can technically place borrowers in breach of terms—often without their knowledge.
3. Cashflow Shock
Landlords expect insurance to “sort it.” When it doesn’t, they’re forced to fund shortfalls personally—often at the worst time.
4. Portfolio Risk
One underinsured property can destabilise an entire portfolio, especially where rental income supports multiple loans.
Why Underinsurance Is So Widespread
Landlords are not careless—the system nudges them this way.
- Insurance is often renewed automatically
- Sums insured are rarely challenged
- Brokers and landlords focus on rate, not adequacy
- Rebuild cost calculators are misunderstood or ignored
- There’s a false assumption that “the insurer would flag it”
They usually don’t.
The Broker Opportunity: From Transactional to Trusted Adviser
This is where mortgage brokers are uniquely positioned.
You already:
- Understand the asset
- Understand the lender’s requirements
- Understand the client’s long-term strategy
By helping clients navigate underinsurance risk, brokers can:
- Strengthen client trust and retention
- Protect future refinancing options
- Reduce the chance of distressed conversations post-claim
- Differentiate themselves in a crowded BTL market
Crucially, this is not about selling insurance—it’s about risk stewardship.
Practical Solutions Brokers Can Champion
Mortgage brokers don’t need to become insurance experts. But asking the right questions makes all the difference.
1. Encourage Regular Rebuild Reviews
Especially:
- At remortgage
- After major works
- Every 2–3 years minimum
2. Flag Portfolio Drift
Portfolio landlords often insure on “rounded numbers.” Encourage property-specific rebuild assessments.
3. Partner with Specialists
BTL insurance is nuanced. Specialist brokers understand:
- Correct rebuild methodology
- Lender expectations
- Portfolio structures
- Claims behaviour
4. Make Insurance Part of the Advice Conversation
Not an afterthought. Not a box-tick. A risk conversation.
Why This Matters Now
The combination of:
- Rising build costs
- Increased regulatory scrutiny
- Tighter landlord margins
Means underinsurance is no longer a theoretical risk—it’s a commercial one.
Mortgage brokers who help clients understand and address this risk aren’t overstepping. They’re future-proofing their advice.
Final Thought
When a serious claim happens, landlords don’t remember the cheapest premium.
They remember:
- Who helped them understand the risk
- Who asked the difficult questions early
- Who protected their investment when it mattered
Underinsurance sits quietly—until it doesn’t.
Mortgage brokers who help clients navigate this risk won’t just protect assets.
They’ll protect relationships, reputations, and long-term business.
Author: Simon Thomas
