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Let’s imagine that you get to a worksite and you see something that nobody likes to see: a floor of peaks and valleys. This generally means that there are issues with either the floor itself or the subfloor below. To rule out the floor coating, measure it with an effective moisture metre to decide whether it is the root of the problem. If the moisture on the surface is below reasonable limits, the next perpetrator on the list is an uneven subfloor. This is something that you certainly want to correct to ensure a smooth and even finished product. So, how are you going to repair an uneven subfloor? It’s not as simple as merely ripping it up and starting it again.

Guides For How To Fix An Uneven Subfloor

Step 1: Assess An Uneven Subfloor

Assess the condition. Is the subfloor made from plywood? Is the concrete? Particleboard? Particleboard. Is the unevenness the product of a poorly constructed subfloor, a problem with moisture, or an uneven joist? Is there an issue with the length of the whole room, or just some parts of it? Is the base of the house in itself uneven? It’s essential to know the essence of the problem before considering if you’re going to resolve it. Note: If you’re working in an older home, try to search for asbestos before you tear it up.

Step 2: Control The Service Standards

If you offer this service to a customer, make sure to control their standards. When you are able to find the issue and decide that you need to tear up the old subfloor and add a new one, or fix the joists that support it, let the client know that the complexity of the job entails more than just building a new floor. Even if you manage to flatten much of the subfloor, you may always end up with a few bumps in the finished floor if the problem is severe or comes from the building base. Please let your customer know about this possibility as well.

Step 3: Different Subfloor Types

Fix that! The method of repairing the uneven subfloor depends on the type of material you are working with and the source of the problem. Here’s how to repair a few different sub-floor types:

For plywood and OSB over joists, make sure the joists are not the source of the problem. Then calculate the difference between the high and the low points of the floor.

For a concrete wood subfloor, you might find this condition in some of the older buildings. Next, calculate the difference between the high and the low points on the floor. If the gap is substantial and the duration of the space runs, you will need to tear up the old subfloor and add a new one to ensure continuity. Fasten plywood on the recesses to ensure that the subfloor height’s inconsistencies are as negligible as possible, and then dry up on the current subfloor and again calculate the gap between high and low points.

Step 4: Use a flooring underlayment

 Use a flooring underlayment to iron out any lingering irregularities. The flooring will help smooth out any residual peaks and valleys in the subfloor and avoid complications down the road. But note that underlying can’t perform miracles, so don’t count on it as your only remedy.

You’ll want to make a call on the underlay based on space’s position and whether it’s above or below the grade. If space is situated above the other building floor, the safest solution is a sound-proof firewall. If space is below the norm, a moisture-resistant underlay is the safest option.

These are some steps that provide an idea about how to fix an uneven subfloor.


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