The short answer
Safety First
Before you touch anything, turn off power to the room if water reached outlets or appliances. Wear gloves, goggles, and a mask to protect yourself from dust and possible contaminants. If you feel unwell, see a doctor. Also, check for any electrical hazards, such as exposed wires or standing water near outlets.
Check for signs of mold or sewage backup. If you see mold or smell sewage, stop cleaning and call local water damage pros. They have the right equipment to handle hazardous materials safely. Mold can start growing within 24 to 48 hours, so quick action matters.
- Turn off electricity at the breaker
- Wear gloves, goggles, and a mask
- Check for mold or sewage odor
- Open windows for ventilation
- Remove all wet flooring and underlayment
Remove Loose Debris
Sweep or vacuum the subfloor to remove dirt, nails, and broken wood pieces. Use a shop vacuum designed for wet pickup if the surface is still damp. Dispose of any soaked padding or insulation in a sealed bag. This step helps you see the actual condition of the subfloor.
Inspect the subfloor for soft spots or warping. Press on the wood to find areas that give way. If you find rot, those sections may need replacement. A water damage inspection can help determine the extent of the damage. Look for discoloration or a musty smell as additional clues.
Scrub the Surface
Mix a cleaning solution appropriate for your subfloor material. For plywood or OSB, use a mild detergent and warm water. For concrete, a degreaser works well. Apply the solution with a stiff brush or mop. Avoid using excessive water on wood, as it can cause further swelling.
Scrub in a circular motion to lift grime and stains. Pay extra attention to seams and corners where dirt collects. Rinse the area with clean water afterward to remove any soap residue. For stubborn stains, a baking soda paste can help, but test it on a small area first.
- Use a stiff brush for rough surfaces
- Avoid soaking wood subfloors
- Rinse with clean water
- Wring out mop or cloth often
- Change wash water when dirty
Dry Completely
Drying is the most important step. Use fans, dehumidifiers, and open windows to speed up the process. Aim for a dry surface within 48 hours to prevent mold growth. If the subfloor stays damp, structural drying and dehumidification may be needed. Keep the air moving to reach all corners.
Check moisture levels with a moisture meter if you have one. Wood should feel dry to the touch and have no visible dampness. If you live in a humid climate, keep a dehumidifier handy during humid months to help with drying. Also, check the subfloor from below if possible, such as in a crawlspace.
When to Call the Pros
Cleaning a subfloor after a small spill is doable, but major water damage requires professional help. The pros use industrial fans, dehumidifiers, and antimicrobial treatments that homeowners rarely have. They also know how to handle contaminated water safely. Attempting to clean sewage or floodwater on your own can pose health risks.
If the subfloor has been wet for more than two days, or if you see mold, call the pros. They can assess the damage and perform deep cleaning after disasters. Related services like subfloor and under-house water leak repair may also be necessary. Early action can reduce the chance of permanent damage.
- Subfloor soaked for over 48 hours
- Visible mold growth
- Sewage or floodwater involved
- Soft or sagging areas in the floor
Water damage does not wait
Water keeps spreading into floors and walls, so it is worth acting early. Calls are answered 24/7.
Call Now (801) 383-0232Frequently asked questions
Can I use bleach to clean my subfloor?
Bleach can work on concrete but may damage wood subfloors. For wood, use a mild detergent and water. If you have mold, bleach may not reach the roots. The pros have specialized mold cleaners that are more effective. Always test any cleaner on a small area first.
How long does it take for a subfloor to dry?
Drying time depends on the material, humidity, and airflow. With fans and dehumidifiers, a wood subfloor may dry in two to three days. Concrete can take longer. If it stays wet after several days, call the pros for structural drying. You can speed up drying by keeping windows open and air moving.
What if my subfloor is particle board?
Particle board swells and falls apart when wet. Cleaning may not be enough. If it's damaged, you may need to replace the affected sections. A water damage inspection can help you decide. In many cases, replacing particle board is the safer option to avoid future problems.