June 26, 2010
In today’s discussion I am going to explain how to install a cultured stone wall. There are many steps in this process but it is a job that just about anyone can do if they can pay attention to detail and proper spacing.
The first thing you need to do is to get your scratch coat onto your structures wall. You first need to cover the entire surface with tar paper either the 15 or 30 weight. You can also use Tyvek, but I feel that the tar paper will give you the best moisture protection. After all your moisture barrier is up you then must install the steel galvanized mesh over the entire surface, this is very important step and must be done correctly, it is what holds all the weight of the stone. You need to place one fastener every 16 inches apart and be sure to hit the studs behind the walls. And then space them about 12 inches apart vertically. You can use a 2 inch roofing nail or industrial size staples that are at least 1 1/2 inches long. After you have all your fasteners in place you then must apply your scratch coat of mortar over the entire surface, this is what the stone will stick to. After you have completed this step it is usually best to let it dry over night before applying stone.
Now it is time to start applying the stones to the wall. Take your stone and apply mortar to all edges till it sortar forms a suction cup, you shouldn’t have to apply any mortar to the center of the stone unless it is really big. After you have the stone prepped push it firmly onto the wall with a slight wiggle motion to set it in place. continue to do this until all stones are in place, try to space stone about 3/8 of an inch apart and try to break up the vertical bond as much as possible, this will make the job look much more natural.
The next step in the process is to grout the empty joints full with mortar. you will need a grout bag, masons brush and a 3/4 inch tuckpointer for this stage of the job. Pump the mortar into the joints evenly and try to bring them out to the face of the stone. The next step is critical in job beauty. Now you must wait until the mortar is firm and partially set up if you attempt this step to soon you will smear up your stone and give the joints an appearance of being torn, which doesn’t look good at all. Once the joints are set firmly rake the joints with the tip of your tuck pointer, the mortar should fall out like a sandy grit, if it is not and still to wet wait a bit longer, alot of this phase has alot to do with temperature of the outside surroundings. after you have completed this step follow up by firmly brushing all the joints out, this step alone will make a huge improvement on job quality if done correctly. After you are done do a thorough inspection and fill any open hole in the mortar joints.
Then thats pretty much it, just waith till it all dry’s. You will notice the the joints will lighten consideralbly once dry so you may want to add a colorant to the grout when mixing to get the desired color.