New house - Smoke smell from fireplace when fire going

[Cluelessone]

Hello! I'm new here, and I have no idea what I'm doing. I'm sure some will cringe as I type this below - but I'm ignorant and want to learn so laugh and then teach me the proper way.

A few days ago I took the cap off (it had some baffles at the top), and checked the path was clear and the flue was clean using a flashlight strapped at the top. I then made a tiny fire and burned one of those creosote cleaning logs. Everything looked really clean, so I didn't bother scrubbing it out. I could see the metal on the flue walls.

Last night I lit my first decent sized fire, using wood from a long-dead tree I cut down on the property (river birch). I assumed it was dry enough to be burned in the fireplace, but it's possible I was wrong. I also believe, after reading a little bit, that I probably used too much paper to get it started.

My main problem is that the "campfire smell" started creeping into the house. The smoke was visibly being sucked up the chimney, but still the smoke smell persisted. I adjusted the logs a couple times to get a full burn during the fire. This morning, it still smells.

The house was built in 1956 and is on a slab. I honestly don't know how well it's sealed, but will note that there are two returns on the ceiling in the same room as the fireplace, and the attic stairs are right around the corner as well as an old-skool kitchen vent.

Questions:

-How can I burn without the smell permeating the house? How can I check my air pressure in the house and start eliminating negative pressure sources?
-What's the best way to start a fire?
-How do I know if my wood is ok to burn? I cut a few trees down and kept wood from the very-dead river birch and a darn-near-dead hardwood maple.

Unrelated question:

-Where's the best place to get glass doors from? I'd like to be able to close them and leave the flue open when I go to bed. This fireplace is an aggravating dimension at 34 7/8" wide and 20 3/4" tall.

 

[begreen]

There is a possibility that there is negative pressure in the house. Is there a door to the attic? Is it sealed or is there a gap at the bottom? On a calm day, if you open a window a little, does air flow in?

 

[Cluelessone]

There is a possibility that there is negative pressure in the house. Is there a door to the attic? Is it sealed or is there a gap at the bottom? On a calm day, if you open a window a little, does air flow in?

I said door, I should have said a ceiling ladder or whatever they're called. It seems pretty snug, but it's definitely possible it's leaking air.

On a calm day I can open the window and don't notice any airflow in or out. I've forgotten windows were open before due to this. Windy days are another story.

Another semi-unrelated question: is it called "tramp air" in the fireplace world? It's a commonly used term in heater fireboxes for refineries etc, but I don't know if the term is relevant for the home.