How to fix broken floorboards under carpet – 3 scenarios

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If you have a broken floorboard under your carpet, it will need repairing or replacing. To do this, you will need to pull the carpet back, in order to access the broken floorboard. Then you can identify the issue and determine the appropriate solution.

In this article, we will look at 3 different scenarios. We will explain how to fix floorboards under carpet, that are broken, damaged, or loose. Explaining the different techniques that can be used to fix them.

how to fix broken floorboards under carpet

Whatever the problem is, it is best to identify and resolve the issue early. This will avoid any accidents and potential damage to your flooring. It will also help you to identify any more serious problems, that could become worse over time if not treated early.

How to remove carpet to access floorboards

If you have never removed any carpet before, it can be quite daunting to simply pull it up. However, it really isn’t that difficult. In most cases, the carpet will be held in place around the perimeter of the room, with carpet grippers.

Carpet grippers are small strips of plywood, with angled hooks that hold the carpet in place. Pulling the carpet from the grippers is relatively easy, and laying the carpet back down once you are finished, is also an easy job. You can simply lay the carpet back to the grippers and push the edge of the carpet back in. This can be done with a blunt tool such as a bolster chisel.

After removing your carpet to expose the problem floorboard, you will be able to get a clearer idea of the problem. Most commonly this will be one of three things.

  1. The board is not sat on a joist
  2. It is not fixed correctly
  3. Or it is visibly damaged

How to fix a floorboard not sat on a joist

If the end of a floorboard is not sat on a joist, this means there is no support under it. This will cause the board to flex when it is stood on, and in the worst-case scenario it will break.

There are two main reasons this happens:

  1. The board was fitted badly to the joists. This could be a board that only just hits a joist, but over time it has moved and slipped off. This can often be the result of damage to the end of the floorboard, which can be caused by wear and tear, over time.

  2. The board has been cut and not supported afterwards. This usually happens when a tradesperson accesses below the floorboards by cutting boards, then fails to add support when it is replaced.

In either of these scenarios, you will need to add a support to carry the board. For option number 1, this can be done quite easily, by screwing a piece of wood to the existing joist.

In the second scenario, you may not have a joist close by. If this is the case, you will need to install a piece of timber below the end of the floorboard.

To do this, cut a piece of wood, that is at least twice as wide as a floorboard. Take this piece of timber and place it under the floorboard, so it under-laps the board either side of the hole. Next, screw through the floorboards either side into the timber below. This will hold the wood in place, providing a bridge support, for the end of your floorboard to sit on.

What to do if a floorboard is not fixed correctly

This is the simplest solution. In this case, the board is not broken, and it is sat on a joist. However, for whatever reason, it has not been fixed in place. This can feel like a broken floorboard when it is walked on, due to movement.

Assuming the floorboard is sat on a joist, and it isn’t damaged, you can simply screw it in place, and this should solve the issue.

What if the floorboard is definitely broken?

If the floorboard is visibly broken, it will need replacing. However, before you replace the board, you should try to determine why it broke in the first place.

Often, a defect in the wood can cause it to crack and break over time. This is not unusual, so assuming there are none of the previous issues, and the floorboard is sat securely on a joist, it can simply be replaced.

When replacing the board, you will need to determine the correct size to purchase a replacement. One thing to consider, is many old floorboards use imperial measurements. Whereas modern boards are usually measured in metric.

This can cause a slight discrepancy in sizes. With that said, it usually isn’t a massive difference (maybe a couple of millimetres). Also, you can source old floorboards if you really want an exact fit. Finally, things like chipboard or even plywood could be considered for minor repairs.

The only time you wouldn’t replace the floorboards straight away, is if there are signs of an underlying issue. This could be something like rotten floorboards, or a visible sign of woodworm. Both of these are serious issues, and you will need to treat the root cause, so it doesn’t spread.

For rotten floorboards, this is more common near walls and is a sign of penetrating damp. You will need to find the cause of this damp and rectify it, before replacing any wood. You should also check joists and remove them or treat them where appropriate.

If you think the problem is woodworm, you can learn more about treating woodworm in floorboards by clicking here.

Conclusion

In most cases, its easy to fix broken floorboards under carpet. Usually, after a quick inspection, they will either require securing properly, or they will need minor repairs or replacement. However, there are cases when a more serious underlying issue can be present.

If there are clear signs of damp, rot, or even wood burrowing insects, you will need to completely fix the issue before you replace any floorboards.