About 6 years ago we had a moisture ant problem near our back door, they are since gone but our problem keeps getting worse. Our back deck may not have a correct flashing near our back door. We are in Northwest Washington and get tons of rain and this caused wet wood and the friendly and hungry moisture ants made our old house their home. Our back door has an aluminum threashold and under it all the wood is rotten, including the sill and the tops of the floor joist headers, the lower area of the door jam is also rotten. It is so bad that an walking out the door is nearly unsafe, the floor near the door on the inside of the house has so much spring and flex when standing, it nearly feels as if one day I will fall into the crawl space below. Our house is only about 15 years old, and this problem desperatly needs repair. I am not by any means a contractor, but really would like to tackle the problem my self. Can anyone provide instruction (with photos or drawings) of how to fix this problem. My main concerns are when I start to remove the threashold how do I fix the sill under the door and walls to the left and right of the door and the joist headers (will I have to jack up the house?) and the floor where it is rotten, and we have vinyl linoleum, will all this need replaced? Also would the door jam need replaced entirely or just the bottom where it is rotten replaced? I can provide photos if I can figure out how to post them. Thanks to all ahead of time.