How to Fix a Sagging Spot in Your Floor

Do you have a spot in the floor of your porch or even your house that is sagging? Are you worrying that it is about to fall through? Do you wonder how you can fix it? Well, wonder no more. With these simple steps, you can reinforce that sagging floor and make it level and safe once again.

If the sagging spot is on the porch you will need to get underneath the porch in order to see what is happening. Since many people close in underneath their porch to give it a more appealing look, you may have to create an opening if one was not left for access. You really need an access door anyway, so this shouldn't be a problem. The opening should be on the less noticeable side if at all possible. Cut the opening large enough for a normal size person to fit through. You should make some type of door that can be closed back and latched to keep animals from getting underneath the porch.

Once you have gained access to the area underneath, you will need to determine what it will take to fix the sagging spot. Most of the time, the problem is pretty obvious. Maybe a board has split or the support post has rotted away. Check to see if moisture is the culprit that caused the problem. If so, you will want to lay down a moisture barrier. This is simply plastic sheeting which can be laid directly on the ground to trap the moisture. Make an assessment of what you will need to repair the floor. For example, if the support post has rotted away, note what size the post is. Many posts are four by fours or maybe six by six. Notice the ground underneath the post. Is it wet? If it is, you may want to consider using a concrete block or pouring a cement pad to put the post on. You can also now purchase special post holders that actually keep the post up out of the water. These holders have small legs and the post fits down into it. They still need to be set on a level and solid surface such as a concrete stepping stone. Or you might decide to replace the old post with a metal support. These floor jacks can be adjusted to or close to the exact size you need. Once you know what you need you can make a trip to your local lumber company or home improvement center. Don't forget the plastic for the moisture barrier.

Once you have gotten the materials you will need to replace or repair the spot, you will need to remove the old or damaged support. To do this safely and to get the floor back up to the correct level, you will need to jack the sagging spot up and support it close to where you will be replacing the support beam. Just about any type of jack will do this simple chore, even a car jack. The most important thing to remember is to make sure you keep the jack level. Place the jack on a concrete block if possible. Place a short piece of two by four across the top of the jack and make sure it is firmly set as you beginning jacking the floor up. The piece of two by four should be long enough to either span two floor joists or run with the one being jacked up. Begin jacking the floor up slowly and have someone up on the floor of the porch to check it with a level. When the floor is level, stop. Measure how long you need your support beam to be and cut it to that length.

Once you have cut your beam, you will want to jack the floor up just a little more. That way you will be able to maneuver the new support beam into place before you start lowering the jack. Once you have your new support beam centered under the joist, slowly begin lowering the jack until the porch sets down on the new beam. You will want to further attach it with nails or screws.

If the sagging spot is just a rotten board in the flooring, simply cut out the bad spot and replace it. Or maybe the flooring has moved slightly away from the joist or crossbeam that supported it. In this case you might be able to just cut a two by four a couple of feet long and "scab" or attach it in to the side of the existing joist or beam. Once you have the weak spot supported, be sure and attach it with screws or nails. This will help prevent squeaks or movement of the floor.

These same instructions will work on fixing sagging spots in the first floor of your house as well. If you have a basement that you actually use, you may have to enclose the support beam or dress it up to look like a column. If the sagging spot is on the second floor of your home, you may choose to hire a professional contractor to repair the problem. More than likely, he will have to either remove a section of the flooring or the ceiling of the room directly below the bad spot in order to determine the problem. If you feel brave enough, go ahead and check it out yourself. You might be able to repair it by simply adding a brace to the existing floor joist.

Any sagging spot in a floor should be addressed as soon as possible. If the spot is due to moisture or water damage, find the source at once. Moisture is a deadly enemy to wood. Wood that is kept dry and insect free will last a very long time.