Here’s an issue you might not know much about. But if you have it, it’s going to make selling your home a more expensive proposition.
When you hire a home inspector, checking for knob-and-tube wiring (K&T for short) is one of the first items on any inspector’s list.
Here’s what I can tell you about it.
What is Knob-and-Tube Wiring?
First, let me tell you in shorthand what K&T is. It consists of single-insulated copper conductors that run within the wall or ceiling cavities. These wires are protected by porcelain insulated tubes and/or nailed-down porcelain knob insulators. Here’s a picture of what it looks like.
This protection is made of flexible cloth insulating sheeving. They’re twisted together and soldered, wrapped with rubber insulating tape or asphalt-saturated cloth and sometimes set into metal junction boxes.
Sound complicated? It’s not really. The only thing you really need to remember is that the U.S. Electrical Code no longer allows new knob-and-tube wiring to be installed. And to make it worse, in most cases, it’s no longer even allowed to be in your house.
Knob-and-tube wiring was commonly used in North America until the 1940’s. So if you’re selling an older home — that Craftsman colonial you’ve lovingly restored — you’re bound to find it. Unless, of course, you’ve updated the entire house, including its innerds.
Why is Knob-and-Tube Wiring a Problem?
K&T has a few issues.
- Knob-and-tube wiring was used during a time when electrical requirements were less demanding. Fewer appliances, no air-conditioning systems, no microwaves.
- K&T never included a safety grounding conductor.
- K&T can become dried out and brittle.
As existing K&T wiring gets older, insurance companies may deny continued coverage due to a perception of increased risk of fire. But what’s most important to downsizers selling their homes is that in many instances, companies will not write new homeowners policies at all unless K&T is replaced.
And if a buyer can’t get insurance, they can’t get a mortgage either.
How Can I Tell If I Have Knob-and-Tube Wiring?
Sometimes it’s easy to tell. There are an overwhelming number of wires hanging overhead and down your basement walls. Does your electric box look like it has too many lines per circuit breaker or too few for the amount of service needed? Dead clear sign.
But sometimes you have dropped ceilings and unless you have some knowledge of electrical wiring, you won’t be able to tell.
My best advice is to get an experienced electrician into your home right away to check it and give you an estimate. The estimate will be based on the amount of knob-and-tube wiring along with the number of outlets and switches you have throughout the house. Each outlet costs a certain amount. In my area, $150 per hole. Then multiply.
Did you just see the word “hole”? Yes, it’s sad but true. The electrician will need to punch holes in your walls to draw up the new wiring. So you’ll also have to add on the cost of repairing and repainting your walls.
Do I Really Need to Fix It?
Let me tell you my story. When we decided to put our home on the market, I discovered I had knob-and-tube wiring.
This came as a shock because we had an extensive air conditioning system. All of our outlets were three-pronged. (Sometimes old-fashioned two-pronged outlets can be a sign that there is old wiring in a house.) Plus, it’s not like anything had ever blown up in the 20 years we lived there.
We decided to fix it before putting the house up for sale. Lucky for us, we had the money and we had to do a bunch of repainting anyway. We figured whoever bought our home would not want to do all the work required for the upgrade. In our case, we were right. We were able to get a maximum amount from an enthusiastic buyer who had two young girls and wanted to move in hassle free.
So This Is Going To Cost a Lot Upfront, Huh?
Here’s one option, especially if you don’t have the money for all the fixing.
Put your home on the market, disclosing the knob-and-tube. Get an estimate for the work to be done.
What will happen is that the buyer will receive a credit at closing for an agreed upon amount of money to get the rewiring done. The new owners will probably want to repaint many of the walls anyway and it’s much easier for the work to be done when all the furniture is gone and the home is empty.
Another option is to sell the house “as-is”. Not the best situation, but sometimes that’s all a seller can do. What do I mean by “as-is?” I’ll explain in a future post.
So — not to panic. Just be sure you are educated about the mechanicals in your home and make sure your agent is able to effectively explain and educate potential buyers about knob-and-tube wiring and the extent to which it exists in your home.