Wood – Does the wood stove pipe have to be chrome to be safe to use

I almost passed on this question, but couldn't resist.

I have been involved in a lot of home energy audits lately. Having spent a lot of time with some very qualified experts, i've learned a lot.

The one thing about a conventional fireplace is that they are for looks only. Even if the wood is free, it is costing you heating costs every time you light it. The real story is that for the chimney to draft properly and not fill the house with smoke, it has to pull tons, yes really tons, of air from the house to feed the flue. Only about 40% of the heat generated by the burning wood is actually sent into the house. The majority is sent up the chimney, as flue temps can reach 600 to 700. In order for this hot air to escape, it pulls the warm heated air from your home. So in essence, you are trading 40% efficient heat for the paid for heat at maybe 80% to 90%, depending on your heating system. Not a good trade, huh?

My advice is not waste your money on gimmicky promises of high efficiency gadgets. Just enjoy the fire as a romantic mood setting with a glass of wine, but don't forget to close the damper as soon as the fire is out to save your heating bills!

The way fire insert stoves work is relatively simple in conversion.

You cut the damper out of the fireplace, run stainless steel pipe (6" dia.) up the inside of the chimney. The lengths are held together with 3-6 sheetmetal screws so this is an actual inside pipe assembly and it hangs off a sheetmetal cap that covers the top of the chimney and is silicone caulk sealed to the top of the chimney flue tile so it's air tight to prevent exactly the type of heat loss you mention. The pipe that extends above the sheetmetal sealing cap gets a standard stovepipe cap to prevent downdrafts and water intrusion from precipitation.

The bottom gets a piece of flex stainless pipe that joins the chimney stack to the stove.

The advantage of this is you are no longer at the mercy of cracked flue tiles and the fire hazard that represents. The 6 inch pipe runs at a higher temperature and tends to not creosote up. There are standard round chimney brushes for these so the soot that accumulates near the top is easily removable by popping the cap off and running the brush and 3-4 rods down the length of pipe.

Depending on where you live and your county's rules, this conversion may require a permit, but it saves you a lot of lost heat and drastically lowers your liability from flue fires.

The stainless pipe will need inspection periodically for pinholes and monitoring for soot buildup and a good brushdown every so often.