If the thickness of the plywood is not enough to support that weight it will eventually cause the shelves to warp.
How to fix warped plywood floor.
This works best for warps that come from humidity or a water spill rather than from a leak that originated below your flooring.
Sometimes even a nearby water source like flooding underneath the house can cause enough of a moisture imbalance to result in warping.
The problem in this case is the weight of the books or other things which are placed on the shelves.
The concave part needs to face downwards.
Most often a warped wood floor is caused by standing water or heavy moisture below the floor due to an unidentified leak or other hidden water source.
Keep in mind that this will require an aggressive amount of sanding in most instances.
The first method to fix a warped floor is to sand it.
The bowing that occurs is actually the plywood shrinking.
Water causes the wood to expand and shrink.
Plan the layout of the plywood sheets so the long dimension of the plywood runs perpendicular to the floor joists.
Sand down the bump in your flooring until it is level with the rest of the floor.
Wood floors usually become warped because of water damage although too much sunlight can also cause boards to warp.
Set your iron to the highest temperature and let it heat properly for about 2 6.
As humidity or moisture from rain water falls onto the wood the lumber absorbs the liquid causing it to expand and bend.
You can flatten them again with hot water and a warm environment.
Another common use for plywood where it has a high tendency to warp is for shelves.
This process will take several hours but once it is finished the plywood will be rejuvenated and ready to use for your project.
How to fix warped plywood shelves.
Now keep your wrapped wood on a flat surface that also will be able to bear the temperature of your iron.
Many floor boards that are warped will need to be removed and replaced.
Plywood pieces can warp if they have been improperly stored or exposed to moisture.
Using warped planks in framing a home or in a sub floor may result in problems as floors and walls begin to buckle.
Wrap your warped wood in two large moist towels and make sure the warped parts are properly covered.