Hey Guys,
I have an old home with a stone foundation wall in the basement which needs to be parged. There are places on the wall where the old cement is still intact. I have chiseled off all of the loose stuff…
Would anyone have any suggestions as to type of cement mix for this project; portland cement, lyme, sand, -proportions, ect…? (Or is is lime?)
Any ideas on prepping/cleaning the walls? Afterwards, a bonding agent was suggested prior to cement..
Thanks,
dan
Replies
Re-cement
Cementing is not my forte, but years ago I did a lot of tuck-pointing on old brick houses, the process was to have a sample of the existing analyzed and then match the composition of the original, this was to be sure the patch would adhere to the original and not crack the bricks or have it fall out.
The problem with the old masonry work is that the mortar was different from job to job.
Maybe someone else with more information will post, luck.
Surface bonding cement
It's been some years since I have done it, but I have used "surface bonding cement" with good results.
This was a product designed to be troweled over the face of dry stacked blocks to create a structural and water tight foundation wall.
I did a couple of crawl space foundations with it, but used it mostly as a parge coating for what you are needing and as a coating over Styrofoam on exterior foundations.
It came as a dry mix bag and contained short fiberglass strands - be careful not to over mix it as the fiberglass strands will breakdown and leave your wall looking "fuzzy". Not a problem for what you are doing but would have a structural effect on dry stack applications.
Not sure of the contents of the mixture, but my experience was that it was sticky as hell and adhered to a variety of surfaces.
I purchased it at block supply houses.
Terry