Is Knob-and-Tube Wiring a Deal Breaker?
(A New Hampshire Homebuyer’s Guide)
Let’s start with the answer everyone wants:
👉 No — knob-and-tube wiring is NOT automatically a deal breaker.
👉 But… it can turn into one real fast depending on the situation.
If you’re buying a home in New Hampshire (especially anything built before the 1950s), there’s a decent chance this topic will come up during your home inspection. Let’s break it down in a way that actually makes sense — without the electrician jargon.
First: What Even Is Knob-and-Tube Wiring?
Knob-and-tube (K&T) wiring was the standard electrical system from the late 1800s through the 1940s. It uses ceramic knobs and tubes to run wires through framing — and at the time, it worked great.
Fast forward 80+ years…
It has no grounding
It was designed for way less electricity
And most of it is now well past its intended lifespan
That’s where the concerns start.
So… Why Do People Freak Out About It?
Let’s separate fact from fear.
⚠️ The Real Concerns:
No grounding → higher shock and fire risk
Old, brittle insulation → wires can become exposed
Not built for modern demand → today’s appliances overload it
Hidden modifications → decades of DIY “fixes” can create hazards
Insulation conflicts → covering it can trap heat and cause fires
🏦 The Big One (That Surprises Buyers):
Insurance companies often won’t cover homes with active K&T
And no insurance = no mortgage = deal… potentially over.
What We See in New Hampshire Home Inspections
Here’s the honest, boots-on-the-ground reality:
In New Hampshire, knob-and-tube wiring is extremely common in older homes — especially in places like Nashua, Manchester, Amherst, and the Seacoast.
During a home inspection, we typically find one of three scenarios:
1. 🟢 Old But Largely Inactive (Best Case)
Mostly replaced over time
Small remnants remain (attic, basement)
No major safety concerns
👉 Usually NOT a deal breaker
2. 🟡 Partially Active (The Gray Area)
Some circuits still powered by K&T
Mixed with modern wiring
May need evaluation by an electrician
👉 Depends on:
Insurance company
Buyer comfort level
Cost to upgrade
3. 🔴 Fully Active System (Proceed Very Carefully)
Large portions of the home still using K&T
Likely ungrounded and outdated
Higher risk of hidden issues
👉 This is where deals get complicated
The Insurance & Financing Reality
Here’s where things get real:
Many insurers won’t write new policies with active K&T
Some lenders (FHA, VA, USDA) may require replacement
Others may allow it with conditions or escrow repairs
👉 Translation:
Even if you’re okay with it… your lender might not be.
Should You Walk Away From the House?
Not so fast.
Instead of asking:
❌ “Is this a deal breaker?”
Ask:
✅ “What does this mean for cost, safety, and negotiation?”
Smart Buyer Strategy:
💰 Get quotes for replacement (can range widely)
🤝 Negotiate with the seller (credits or repairs)
🧾 Check insurance BEFORE closing
🔍 Have a licensed electrician evaluate it
Pro Tip for Realtors (and Buyers)
Knob-and-tube wiring is one of the most misunderstood issues in real estate.
A good home inspection should:
Identify where it exists
Clarify whether it’s active
Explain real risks vs. theoretical ones
👉 It’s not about killing deals — it’s about removing surprises
How This Fits Into Your Home Inspection
If you’re buying in NH, this is exactly why a thorough inspection matters.
👉 Other related reading:
The Bottom Line
Knob-and-tube wiring isn’t an automatic deal breaker.
But it is a conversation starter — and sometimes a negotiation lever.
👉 The real question isn’t “Is it bad?”
👉 It’s “What does it mean for THIS house?”
And that’s exactly what a good home inspection helps you figure out.
