Tradroofing.com launches first Vlog. Lime putty mortar plus review of Old House Handy

Tradroofing.com launches first Vlog. Lime putty mortar plus review of Old House Handy

I open this note with a heavy heart.  You see.  I spend a fair amount of time online commenting and educating on various forums and sometimes we can get a little heavy handed.  I didn’t want to open with a critique but this is pretty important as it could have disastrous consequences if this recipe is followed on a structural build.

A few years ago, I made a comment on a youtube video about lime-mortar for tuck pointing.  The issue had to do with the mix ratio.  She calls for 2 parts dry lime to 3 parts sand.  This is a big mistake.

2 parts dry lime to 3 parts sand actually makes a mix that is a ratio of 1:6.  The reason is, dry lime shrinks 75 percent by volume when you add water to it.  The classic ratio for lime putty mortar is 1 part lime PUTTY to 3 parts sand. Lime putty is a creme cheese consistency mix you get by slaking burnt limestone.  you would need 4 parts dry lime to 3 parts sand in order to make a successful mix.  

I made a comment stating this on the video, but i veered off more into language that had to do with the technique of tuck pointing rather than the mathematical error that was at the root of my concern.  

Most of the comments divulged into the usual debates about NHL vs Hydrated lime, and honestly this wasn’t the point of the discussion I was trying to get across in the first place.  My real issue is with the math.  I’m trying to stay scientific in my response.  I really like the rest of the content Old Home Handy has on youtube, but this recipe could be dangerous if an unsuspecting builder gets ahold of it and scales it up.  Catastrophic.

I Present my first Vlog for tradroofing.com as a way to lead by example, I’ve shown all my math… what say ye?

Hit me back, sister. I’d love to see an updated video with adjusted ratios.  -Kurtis

(Tradlabs, please remove your mortar video before someone uses it. https://youtu.be/4svqXjwaB5w this video is the one I’m referring to. Thanks, and I love the rest of your work… we just really can’t have that info out there… it’s bad for the trade.)


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