Sauna drip edge to deflect water from walls and prevent mold.

The idea of a drip edge is simple. The sauna will have heat, steam and possibly water. All this will roll down the cedar walls and towards the floor. To prevent any water accumulation in the corners where the walls meet the floor, we want to deflect the water towards the drain. That’s where the drip edges come in. Basically, drip edges are pieces of “treated” wood around the perimeter of the hot room with a flat area on top the width of a cedar panel board (1/2 inch) sitting on it and a 45 degree slant from there towards the floor to deflect moisture. A photo is worth a thousand words:

Drip edge up close 1.

Drip edge up close 2.

To make the drip edge I used a table saw. First, I set the cut width to 1.75 inches and ripped a 2x4 treated piece of wood in half. That left me with two 1.75 inch pieces. 

Table saw blade setting to split a 2x4 in half.

Then, I set the table saw to ½ inch width, set the blade to 45 degrees and cut the 2 pieces of wood. Now I had 2 drip edges. 

Setting a table saw to 1/2 inch width for the 45 degree cut for drip edge.

I then measured the length of each wall that the drip edges will be attached to and made 45 degree miter cuts on each side so the drip edges came nicely together at the wall corners. Now this is why I didn’t glue the 2 sheets of PVC floor liner membrane I put down. I needed the membrane liner to be able to move snugly in to the corner under the drip edge by pushing on the drip edge. Once everything was good, I used a brad nailer to attach the drip edges around the room. Later when I started putting up the cedar tongue and grove, it all worked out very nicely.

A Glimpse In To The Future:

The drip edge is the first piece of wood sitting on the liner. The cedar rests on top of it.