Top Subfloor Problems and How to Fix Them


How do you truly know if you’re dealing with subfloor issues? A subfloor issue can not only cause damage to the structure of your home but can also create future problems for your new floors after installation. You may start to see issues immediately, or it could take time, even years, for them to show up later down the road.

At Flooring Solutions, we’ve seen all types of subfloors in good shape and others that have even slightly shocked us. We understand our massive responsibility to ensure a client’s subfloor is repaired and in good condition, before new floors get installed on top of it, and we take floor preparation very seriously!

With most problems come solutions, and we want to be your resource to talk openly and honestly about those. Whether hiring a professional like Flooring Solutions or looking to make these repairs yourself, we want to arm you with the proper tools to address your subfloor problems and get them back in good shape!


subfloor repairs


Problem #1: Squeaks in Your Subfloor

If you’ve noticed squeaks from your subfloor lately, it could be due to an underlying issue. Loose nails can cause squeaks in your hardwood or plywood subfloor installation. While these squeaks may be annoying, if you could prevent or fix them, wouldn’t you want to?

So, how do you fix this issue?

Fixing Squeaks in Your Subfloor

  1. Tighten loose screws or nails: Sometimes, those annoying squeaks in your subfloor are simply caused by loose screws or nails. Imagine walking across your living room and hearing a creak every step of the way. By taking the time to identify the loose screws or nails and giving them a good tighten, you may be able to eliminate those pesky squeaks for good.

  2. Add additional screws or nails: If the subfloor is not adequately secured, adding other screws or nails can help reduce movement and eliminate squeaks. Think of it like adding a few extra nails to ensure a photo frame is secure or a wobbly bookshelf doesn’t fall over.

  3. Install blocking: Blocking refers to installing additional lumber between the joists to help stabilize the subfloor. This can be an effective solution for eliminating squeaks caused by subfloor movement. It’s like putting additional support beams under a wobbly staircase, ensuring it feels solid and secure with every step you take.

  4. Apply lubricant: Sometimes, squeaks may be caused by friction between the subfloor and the framing. Applying an oil such as powdered graphite or talcum powder can reduce friction and eliminate squeaks. Think of it as giving your subfloor a little massage, making it smoother and quieter with each footfall.

  5. Replace damaged subflooring: In some cases, squeaks and noises won’t come out. That’s likely not the answer anybody wants to hear, but replacement may be the last option if that’s the case.

Free subfloor evaluation


Problem #2: Stains and Pet Odors on Your Subfloor

Just imagine walking into a room and being greeted by a strong pet smell that lingers in the air – yikes! Odors and pet stains on your subfloor can indicate the presence of moisture and potential mold growth. Pet urine can penetrate the subfloor, causing an unpleasant odor and possible damage to the subfloor and structural supports.

Removing Stains & Pet Odors from Your Subfloor

  1. Clean with a mixture of water and vinegar: A solution of water and vinegar can effectively remove pet odors from subflooring. Mix equal water and vinegar and apply to the affected area with a mop or sponge. Allow the solution to sit for several minutes before wiping it away with a clean cloth, taking with it those pesky pet odors.

  2. Use an enzymatic pet cleaner: Sometimes, ordinary cleaners just don’t cut it. Enzymatic cleaners are specialized cleaners designed to break down and eliminate pet urine and other organic matter. These cleaners can be found at most pet supply stores, effectively removing stains and odors from subflooring.

  3. Apply a sealant: After cleaning the subflooring, applying a sealant can help prevent future pet stains and odors. A sealant creates a barrier between the subflooring and any potential contaminants, making it easier to clean and maintain. It’s like applying a clear coat to your car, providing an extra layer of protection against dirt, stains, and odors.
  4. Replace damaged subflooring: In severe cases where it has been extensively damaged with stains and odors, it may need to be replaced to eliminate stains and odors.

It’s important to note that these solutions may only work for some stains and pet odors on your subfloor.

hardwood subfloor

Problem #3: Uneven subfloor

An uneven subfloor is a surface beneath your flooring that is not level, meaning it has low and high spots. It can also make it difficult to install new flooring. If you notice an uneven subfloor, it’s best to have it evaluated by a professional to determine the cause and the best course of action.

Leveling Your Subfloor

  1. Use a leveling compound: A compound can be poured onto an uneven subfloor to even it out. The mixture will fill in any low spots and create a smooth and level surface for your flooring.

  2. Sand down high spots: If only a few elevated areas are on your subfloor, you can sand them to create a level surface. You can use a power sander to smooth down the high spots carefully. However, it’s crucial to exercise caution and avoid sanding too much, as you want to avoid creating new low spots. By selectively sanding down the elevated areas, you can bring balance to your subfloor and prepare it for a flawless flooring installation.

  3. Install additional subflooring: Adding a layer of plywood or other subflooring material can help out an uneven subfloor. This can be particularly effective if the existing subfloor is deteriorated or damaged. By installing plywood or another suitable subflooring material over the existing subfloor, you create a fresh, level surface to work with.
  4. Address structural issues: If the unevenness is caused by structural problems, such as sagging joists or foundation settlement, it’s essential to address these issues before attempting to level the subfloor. Consult with a professional to ensure proper repair, like a structural engineer.

We fully understand that these solutions may be above your abilities, or maybe you just don’t have the time to do them correctly.