Rotten wood above a shower

[Simon Kennedy]

We found some thick beams above what will be our shower area:

http://i2.photobucket.com/albums/y30/simonmotorbike/Flat%20bathroom/beams.jpg

I need to cut into them in order to increase the headroom in the shower. Any reason why not? They are about a foot thick: four or five inches off wouldn't hurt now would it?

They aren't supporting anything that I can see, other than stopping the three floors of concrete blocks above the window coming down.

I guess that there is a treatment for wood out there somewhere that will stop them rotting?

 

Simon