I don't think he meant for you to seal in the sump, but to be sure it's well closed, covered, or ?? (not knowing it's actual set-up). And if you have been burning a lot of wood, or candles, and the house is otherwise maybe sealed up too well trying to save money, make sure there's better air circulation, because burning anything (even regular logs) allows various chemicals to be emitted, and that's probably why he asked about headaches. You need to make sure the atmosphere's not just economically sound, but healthy!

There are several ways to seal the sump pump opening. The quick and dirty way is cardboard and duct tape. The problem is, that opening is for water to enter, should the floor flood. I would certainly want to know where the particulates are coming from...Do you have an oil or coal furnace? A cracked heat exchanger would cause this. Also a leaking wood or pellet stove. If candles are causing it, you must burn a heck of a lot of them!!!!

He asked about the headaches because of possible CO(carbon monoxide) contamination. If don't have them already get a CO detector for each floor of your house.

thank you, lucy, irisman, and joed!
It's a sump pit that has a pump in it... there's a separate drain in the area for "flooding".. yikes... he said there are soil gases that are doing much of this problem... and that I should get radon testing right away... I do burn candles, but I guess "a lot" is relative... I don't burn them all the time by any means. The furnace is gas, no wood burning here.
The health dept would take $100 to come out and see for sure what this is. Good grief. This house is not even one year old yet.
We do keep the thermostat at 60 or 61 most of the time, unless we have company of course! lol... although most visitors know to wear warm clothes and bring something to wear on feet besides the shoes they came in with.
Thanks again for all the help and suggestions.
Let me know if you think of anything else.
peace,
Elle

I don't get how a sump could cause "carbon particulate." That's from combustion - candles, furnace, wood stove or fireplace. If you're burning a LOT of candles all the time, that could be the cause. A couple years ago there was a big issue with candles with wire-center wicks where the wire was lead. People who burned them a lot had their entire houses full of lead contamination on every surface. In your case, you've at least got soot which is a known air pollutant. I just reread and noticed you said it was on exterior walls! That's probably not from candles inside your house.

If you don't think you have a combustion source that could be causing this, I'd get a mold test and forget what Mr. Health Dept.

What state are you in, and how's the humidity and temp right now? Are you in a humid climate? Any of your neighbors have this problem? Are there houses the same design/construction/age?

Elle:

Almost every time I ran across this in many years, this is "Black Soot Deposition". Google those three words and you will see plenty of information about the problem. You statement "I do burn candles, but I guess "a lot" is relative" could be your answer but not necessarily.
If it is the candles, itÂs not how much you burn but the type you burn thatÂs the problem. Soft wax, candles in jars, highly scented candles and wire core wick candles can cause this. When you look at these candles burning, you can see an erratic flame and black soot rising above. That black soot could be what you are seeing around your house. Lift pictures from the wall and you could even see the soot ghosting on the wall behind the pictures as well.
If you have an oil furnace, that could be a possibility but I seriously doubt if itÂs a puff back problem as they tend to be far, FAR worse.

There are some factors here that cause this. Forced air which could be drafts or the HVAC system, the HVAC system is more likely to distribute the soot since your house is new. Gravity and electrostatic forces help to attract the soot to certain locations. Static electricity is whatÂs causing the soot to attract to the ceilings. Finally, moisture in bathrooms, kitchens and next to windows will attract the soot. Very small amounts of moisture (condensation) will be found around windows.

If it is BSD and IÂm sure it is, the thing to do is find out where the carbon is coming from. Do you have a gas stove/heater/fireplace? If one of those units is not functioning properly, they could be the cause of your soot. Sump pump, doubt it seriously, soot is not coming from a sump pump. Outside sources such as tire dust can do this but your home is new, probably very tight and unless you live by a major traffic area, again, not likely.
Give me some feedback as to systems in the home and I can assist further. Hopefully itÂs just the candles.

Ooops, after rereading your post about the black where ceiling joists would be, I misspoke. ThatÂs an issue of the floating particulate stick more on cold surfaces than warm surfaces. During cold weather, the areas of ceiling below the joist are colder due to less insulation. Those ceiling joists act as a thermal bridge and allow heat loss this making those areas colder. Static can play a role attracting soot but your ceiling issue is due to temperature differentials.

Radon is a clear odorless gas. It won't make black marks on your walls.
If you can see the outline of the ceiling joists that is called thermal bridging. Lack of insulation over the joists will allow the section of ceiling in contact with the joist to be colder than the rest of the ceiling. Water will condense and dirt will stick to those areas.