How to install an interior stone wall
A stone wall in your house will look great and you can do it yourself with these handy tips and advice. This tip also works for stone veneer, faux stone, and brick veneer.
Back Preparation:
On cinder block walls or unpainted brick walls, stone can be glued directly to these surfaces without the need for additional coats.
On wood or drywall, add a layer of the tar paper starting at the bottom and working your way up overlapping the paper 4″. from the bottom working up and over the overlap by a couple of inches. Use nails or screws that they go into the studs by an inch and a half. A tip here would be to add a washer to your nail or screw to help hold the cleat. Attach the cleat to each stud and no more than 8″ apart. Wear gloves when working with the lath, it will chew your hands while working with it.
Surface Preparation:
Cover the lath with a ½” coat of mortar or a starter coat and allow it to dry for about an hour. When applying the starter coat, use a thick brush to score grooves in the mortar so the next coat has something to hold onto Mortar should be 1 part “N” type cement and 2 parts masonry sand. Mix with enough water to form a putty consistency, this formula can also be used to set stone and grout joints.
Stone Application:
Most stone veneers are easily shaped or cut as needed. Cutting or shaping can be done with a circular saw with a masonry blade, a wet saw, or a grinder with a masonry cutting disc or diamond edge. A hammer and chisel will cut the stone, hit the chisel on the stone until it splits.
Butter the stone by adding about ½” to ¾” of mortar to the back of each stone before gluing them to the wall. Start at the bottom and push the stone firmly against the wall causing the mortar to ooze out around the edges of the stone. If the stones move when you drop them, the mortar may be too thin and you will need to add more cement and sand until it is tacky. I found that adding a bit of masonry lime to the mix will make the stones stick better.
As you work on the wall, you can use some wood or plastic spacers to help support the stones until the mortar dries.
Be careful not to get too dirty with the mortar and cover the entire visible side of the stones. You need to keep them as clean as possible for the best finish.
Getting your joints right:
After about an hour, when the mortar has dried a bit, push the mortar into the joints. This can be done with a joint tool or a rounded stick. I have found an old spoon or even a paring knife that works well for this.
Once the above is complete, wire brush any excess mortar from the face of the stone and clean the joints with the wire brush and a broom.
Grout:
Now is the time to grout the joints and for this you will need a bag of grout. Mix the mortar until slightly runny and fill the bag halfway, roll up the bag and squeeze with the other hand forcing the mortar into the joints. The hole in the bag should not be more than ¾”.
If you do not grout the same day, be sure to leave the stones clean and wire brush any mortar from the surface of the stones before it hardens.
Helpful tips for placing stones:
- Place the largest stones on the wall first before you start cutting other stones to fit.
- When cutting stones that go above eye level, place the cut edge up and below eye level, place the cut edge down.
- Keep the joints tight and the stones close together, this will help make your wall look more attractive.
- Use contrast for a better look, use large stones next to small stones, dark stones next to light stones, heavy texture near smooth stones, etc.
- Place the stones so that the joints are not in a straight vertical line between more than two layers of stones.
- Some color in the mortar could be considered to blend in with the stones.
- Cleanliness is important, keep hands and stones clean and remove excess mortar before it dries.
- Enjoy your new wall!