This is a brief description of how to build an interior rock fireplace around a fireplace insert.
Before you start this project you will want to make sure that your floor can support the weight of the stone.
1. Frame out and install fireplace to manufactures specifications. This is not a complex job on a scale of 1 to 10 it is a 6.
2. Once the framing is completed and the sheet rock has been installed you can start the chimney process. staple up Aquabar or other moisture barrier paper, overlapping the paper slightly. This can be attached with a common staple gun.
3. After the paper is up the next step is to put up diamond mesh wire. People call this different names but if you go to a specialty store or big box store they will usually know what you are talking about. Install this mesh wire with a air powered stable gun using 2″ staples. Making sure to staple into studs. It is also a good idea to staple between studs. You want to install the mesh wire so that the grain flows upwards. This will make sense once you look at the mesh wire. This will allow the scratch coat to stick to the mesh wire. Slightly overlap the mesh wire.
4. Next you will want to attach metal strips to the surface. These strips are thin, ribbed, flat pieces of metal approximately 1/2″ by 6″ with approximately 6 to 8 holes in it. These are nailed into the studs approximately 8 to 12 inches apart with 16 penny nails. Alternate the layout on each stud so that they are staggered on the wall. Then bend the metal strip approximately 2 to 4 inches perpendicular to the wall, depending on the thickness of your stone.
5. Once the mesh wire is securely fastened you can begin to put on your scratch coat. There is a lot of different types mortar that will work for this. If you go to a home improvement store you will see some that are recommended for scratch coats. It is not as critical to have quality mortar for this part. Mix your mortar according to the instruction. You will get the hang of mixing it to a good consistency over time. Do not mix the entire bag. Mix a quarter of the bag at first and see how fast it takes for you to use it. The mix will dry out fairly quick depending on your climate. If you live in a high humidity climate this will give you more time to work with the mud. Once you have the mud mixed take a pointed trawl and start spreading the mortar over the mesh wire. You want to completely cover the wire. Let this dry (approximately 24 hours depending on humidity). Scratch up the surface of the scracth coat with the trowl. This is supposed to be a rough texture.
6. Now you are ready to apply the stone. This project is for flat stackable stone such as slate (Montana Bronze Ledge Stone or Bitteroot Ledge stone. The type of mortar for the stone application that is good, is called Type S spec mix. The natural stone will have to be cut with a wet saw. There is just no way around it. The stone comes in bulk and will have some natural corners, however you will have to cut some of the corners. When you make cuts for pieces angle the cut towards the back side of the stone. This will allow the edges to butt up closer. Overlap the corners and make sure you follow a plum line from the ceiling or constantly measure the distance from the wall. After you have enough stone cut you are ready to start building. Apply roughly a 1/2″ thick coat to the scratch coat and smoth it out (nothing fancy) then apply mortar to the back of the stone (approximately 2 to 3 inches). Stack the stone flat on top of each other and butted against each other.
This is a very labor intesive job. Tools needed are a wet saw, mason hammer, trowl, some sort of tub to mix mortar in, tape measure and level. Good luck, this is not as hard as it seems but it is very time consuming.