I plan to repoint my stone house, and need a fail safe historically appropriate lime mortar recipe. Any advice will be most appreciated, thanks.
Natural cement has been produced in Rosendale NY since about 1830. It's properties were similar to Portland cement, and it was utilized in important masonry structures such as the base of the Statue of Liberty, the stone towers of the Brooklyn Bridge, the United States Capital, an unimportant structures, like the stone house I grew up in, 3 miles from Rosendale, built in 1938. There is no reason to believe that such cement was unknown in Canada at that time.
Good info Richard. I am saving your formula for my own use in the future. I have a lot of minor issues here and there where mortar is missing. So, I will get the ingredients, but make it in a smaller batch.
in your mortar recipe, what does the C stand for in 4 C white, non-staining Portland cement?
"C" means cups. As in a recipe for cooking.
Anyone have a good mix for lime mortar without portland cement? I would like to make my own for my foundation work (Bec that stuff from Palmer lime works is kind of expensive with the shipping). I would save the other stuff for the brick repointing I have been doing.
When working with Natural Hydraulic lime mortar in repointing, I read that it is advisable to keep the mortar, in the joints, damp. What would be the best way to do that?
A sheet of burlap, hung over the repointed area and kept damp with a sprayer.
Thank you for your prompt answer. This might be a silly question but, how do you attach the burlap to the building? Duct tape or some masonry anchors....
I'd staple-gun it to a piece of 1x3 strapping and either attach it to your verge board or maybe use concrete nails into mortar joints? Not sure how heavy the thing will be when wet. I'll be exploring both options myself later in the summer.
Yep just use some masonry nails right in the mortar joints to hold the burlap up. Every once in awhile I just mist it to keep it wet so the mortar doesn't dry too fast. So far.. good results. I need to start making my own mortar mix since the pre mixed stuff is quite expensive (mostly due to shipping).
Yes I thought about that too. but Won't the nails weaken the mortar though?
I suggest Lime Works in PA. They have a vast amount of info. Our home is also fieldstone and is in a freeze area. They have been a great help. They ship anywhere as far as I know. But the best is the knowledge and help they offer. I would never use any Portland in my mix. Our house is over 200 years old without any Portland...the way I look at it is if it has worked for 200 years why mess with it? Sounds like your house is the same as ours...2 feet thick structural walls plastered directly on the stone on the inside.. I don't even have any cracks in the plaster in our house!