This wiring, from 80-100 years ago, has not aged gracefully. It is considered a fire hazard by most insurance companies. Our clients are often told that they cannot get insurance, or they can only get insurance if they promise to remove the knob and tube by a deadline, like 30-120 days after closing.
Do you run away from a house with knob and tube wiring? It depends on how much there is and if you have the funds to replace it immediately.
Help with funding. MassSave has an interest in seeing you remove your knob and tube. They are prohibited from insulating your walls with knob and tube wiring. Why? Knob and tube is designed to be air cooled; if you insulate around it, it will overheat.
Second, once you insulate, it is harder to do electrical work in the wall cavities. MassSave has this funding to help you afford the insulation that they really want to put in your house.
Blue edits added in 2019. The program has changed. When I wrote this blog entry in 2017, MassSave
is was helping with knob and tube wiring removal. This is was a grant – not a loan – of $3000. Update: in 2019, knob and tube removal is covered as an interest-free loan, no longer a grant. Here is the webpage for that information. (link)
What do you have to do?
- You have to have an energy audit. They will inspect for knob and tube at this time; they just say whether it is there, not how much there is. The house has to need wall insulation (if it has none, it needs it!) You have to agree to do this insulation. The good news is that the insulation program is still a very good deal. It has deep discounts on doing this for your house.
- You get an electrician to confirm how much knob and tube wiring is there. You apply for a
grant up to $3000loan up to $10,000 to offset that cost. You show that you hired an electrician who removed it to get the grantloan funds.
Here’s how I think of it.
You need to insulate in order to qualify for the knob and tube grant. Suppose you have $10-15,000 of electrical work to do before you insulate your walls. Plus, you are committing to the cost of insulation (about $3-4000 with the rebates.) That may break your new homeowner budget, even with a $3000 grant or a $10,000 loan payment.
Things to think about when evaluating this:
- Estimated cost of knob and tube removal.
- Estimated cost of other old wire removal and electrical upgrades. (It is much better to complete electric upgrades before insulating the walls.)
- Estimated cost of insulation.
- You need to get an energy audit and estimates for insulation.
- You need to get electrical estimates.
- You need to get the knob and tube removed by the insurance company-imposed deadline.
In the past, more than a few circuits with knob and tube wiring fell into the “run away” category of problems found on inspection. Knob and tube wiring is a safety issue. If there is knob and tube in a house you are thinking of buying, find out the extent of it before deciding whether to do ahead. But, if the problem is pandemic in the house – every outlet is ungrounded and every overhead lighting fixture has no switch – the “run away!” rule applies.
It makes economic sense to rewire before insulating the walls the wires run through — whether you are changing knob and tube or other old wiring. This includes upgrades that require new circuits, like adding outlets. This work can run more money than you may think. Electricians spend a lot of time snaking wires through walls and you pay for it. If they are snaking through insulated walls, those cost are even higher.
If your electrical estimate is in your budget, I recommend you benefit from these programs. It will save you a lot of money. It will pay back in lower heating bills and peace of mind over time. But, you have to be prepared to navigate the insurance bureaucracy and MassSave’s bureaucracy.