Why is my shower enclosure leaking?

All the caulk in the world may not prevent your shower and glass door enclosure from leaking.  In fact caulking can make it worse.

I have done posts in the past about not caulking the connection where tile shower and/or tub enclosure meets the tub or the one-piece shower base.

In the following picture one can see a typical tile shower and its one-piece plastic base.  

These types of shower assemblies are very common in modern construction and perform very well when installed properly.  

While I don't want to get too technical, suffice it to say that if the connection is caulked, any moisture that eventually finds its way through the grout lines (and some will over time) will not have a route of escape.  The moisture is then trapped behind the tile.  

This results in unsightly mold growth behind the caulk around the base of the shower (or tub) and in many cases will result in the water being directed "outside" the shower where it can find its way into the wall and floor outside the shower.  

Damage to the baseboard visible in the picture below is very common with this caulking mistake.

It is best practice to only grout the wall/shower base connection.  It is also important to make sure the weep holes built into the shower base is left open---as an escape route for trapped moisture.  

Tubs do not have these weep hole details so not caulking over the grout on a tub/tile wall connection is even more important.

It takes considerable attention to detail to get these connections sealed properly. 

This improper caulking detail is not the only cause of damage like this to the walls and floor outside of the shower---but those other reasons will be the topic of future posts.

Charles Buell, Seattle Home Inspector