Home Heating Oil Emissions Staining Shingles and House Siding

When we asked why we never observed the rust staining on our roof or house siding on our other homes that burned home heating oil each expert indicated it was due to the low clearance steel chimney that connects to our furnace.

As they explained to me, with masonry chimneys the home heating oil combustion emissions typically adhere to the side of the masonry chimney flue and thus the staining stays inside the chimney. With the stainless steel chimney, however, the emissions do not adhere to the side walls of the chimney and thus much more of the emissions exit the top of the chimney.

When they do, some of the home heating oil combustion emissions (exhaust gas containing minute particles) end up landing on the shingles. Over time the minute rust looking particles build up causing an unsightly mess on the shingles. Moreover, some of the rust looking particles end up washing off the roof and hitting our deck below when it rains. The dirty rust color rain run-off then bounces up off the deck and splashes on the house siding. So as a result, we end up with a rust stain look on portions of the deck and the adjacent house siding. The home heating oil experts indicate we have two alternatives. Well actually three, if you want to count periodically going out and cleaning / repainting the deck and house siding. And this choice doesn’t address the staining on the roof.

The first choice, and a very expensive and difficult task to do, is to replace the stainless steel chimney with a masonry chimney. In our case this would be a major effort and would tear up both the inside and outside of our home for a number of weeks.

The second choice that they recommended was to replace the oil burning furnace with a gas burning furnace, and in our case, a propane burning furnace. A gas furnace burns much more cleanly and as a result there would be no combustion emissions that would stain the home. It’s also the less expensive choice, and, won’t impact the interior or exterior of our home during the installation the gas furnace. It is this second choice that we’ve agreed to eventually do. Besides eliminating the staining issue, the gas furnace is much cleaner burning and thus more efficient. In addition, gas furnaces are lower maintenance compared to oil burning furnaces.

So if you having a rust stain color on your roof shingles, and possibly on the side of your house or deck, then chances are you’ve got a stainless steel chimney, and connected to it is an oil burning furnace.