What is pressure treated lumber?
In: Engineering
Most wood, especially softwoods commonly used in construction, rots.
You can delay rotting by impregnating the wood with chemicals that make it unpleasant to the bacteria & fungi that rot the wood. But getting chemicals into the wood is sloooooow…unless you force it in with pressure!
Pressure treated wood is normal wood that they’ve punched holes/slots in, then forced a chemical solution in under pressure, then dried, leaving the chemicals behind. It lasts longer in wet/decay conditions than normal wood. Commonly used for fences, decks, the lower parts of foundations, playgrounds, anywhere that wood will routinely get wet.
Wood is naturally very porous. This creates a huge number of places for moisture damage to start, fungi to take root, etc.
Pressure treated wood has preservatives applied to it and then is placed in a highly pressurized chamber. The high exterior pressure forces the preservative chemicals deep into the pores of the wood, so it is not merely an exterior coating.
This makes it far more resistant to rot, fungi, and insects.
To add on, the wood is dried in a kiln first to remove excess moisture. This allows it to absorb more of the solution.
Latest Answers