Contractor Talk - Professional Construction and Remodeling Forum banner

I need a good stone foundation ratio.

15K views 112 replies 18 participants last post by  Fancis Casini 
#1 ·
I got tasked with rebuilding a stacked stone foundation from an early 1800's house (I am going to be there forever).

Two walls caved in, so I excavated and tore down the walls, dug down to the cobble trench footer they made, leveled with crushed stone and started building again, but I need a decent mix design.

The Art of the Stone Mason says to use 1-1-7, I tried it out yesterday and it seems a little rich to me, what have you guys used with success on something like this.

Normally on patch jobs I just get bagged Type N, but it's not practical for such a large project.
 
#44 ·
Personally I hesitate from using a straight lime mix below grade even if that was what was there previous (if rebuilding not repointing). Roots will eat their way through a pure lime mix very easily. If rebuilding below grade I'd want something at least approaching a type N unless it's been shown that it is too hard for that particular stone. If it were I'd be questioning whether it was an appropriate stone for below grade use.
 
#45 ·
The stone is less than desireable to say the least.

Not to say it isn't a strong stone, just ugly as sin. Most of our fieldstone around here is either bluestone or shale, the shale typically isn't used in walls though. I wish we had granite laying around, but it's non existent from what I have seen.

They did a rubble wall (poorly in my opinion) to grade, then topped it with big cut stones above grade to make sharp corners and straight lines.

The original had almost no bonding stones, it was basically and 18" cavity wall filled up with crap as it went up. I extended it in 2".

If I can ever get moving again on it I will post some progress pictures, I have to try to source some cut stone for the top that has been weathered, might have to get new stuff and sandblast it.

It is supposed to snow 3" here tonight, and be below freezing for the next few days. March came in like a lamb this year, and is going out like a lion trying to rape me.
 
#47 ·
It is supposed to snow 3" here tonight, and be below freezing for the next few days. March came in like a lamb this year, and is going out like a lion trying to rape me.
Welcome to my world...70s in here midst of month...lamb turned into wolf in sheepskin...raining non stop or drizzling.

Have to put 8 thin blocks into retaining wall for a customer(5 hours worth of work) for 600$ i have rescheduled it 7 times already.
Not to mention halt on all other work.

Oh well. :sad::sad::sad::sad::sad:
 
#56 ·
If not able to burn up a batch of mud then doing something wrong, water draws to top so need to temp in wheelbarrow, and dry mix needs to stay temped so doesn't flash. In more dry weather soak bags and lay on top of mud from sun. Yes you can have guy make mud, and tend it.. As well as tend everything on the jobsite, including cuts or what not so I don't see the waste. As for not being able to use portland cement such as leahigh ironclad I/II as a binder with only sand and water is 100% inaccurate. To be honest I have never seen 1 person ever use lime as an additive. Mainly, acrylic, antifreeze and color.
 
#59 ·
I think JBM was right...this could go on and on.

And it's a pretty good bet that most of the masons on here understand tempering mortar 101. My point was simple...constant re-temping by adding water weakens the mix. And that's true whether you use it up fast or not. If that's not what you meant or do then my bad.

Personally, I don't want to try and convince you that your opinion on using straight portland for stonework is incorrect. Do some research and you'll see for yourself.
 
#58 ·
I can see using a blowtorch to edge bluestone after chiseling it, I don't understand your analogy.. I learned my methods from a MA level 1 licensed construction supervisor.. What I have for mixes from strongest to weakest goes in this order for what it's worth:

Load-bearing mortars have portland. non-bearing mortars have cement and lime as binder. Good load bearing 1 port and 1-2 1/2 part sand.

non load bearing mortars can consist of from strongest to weakest.

one:1 portland, 10-15% lime, 3part sand
two:portland or white cement, 1/4 part lime, 4part sand
three:cement, 1/2part lime, 4prt sand
four:cement, 2part lime, 6-7 prt sand
five:lime 1 part,5-6 part sand
 
#65 · (Edited)
Bricklayer I worked for told me that Gingerale was a good cold weather additive. Hmm makes sense I guess, something in the carbonation? "Or Soda water?" I say. "NO!!!! Has to be Gingerale!!!!

Weird

And JD3, my comment about the blowtorch. There are things that you CAN do, like getting totally drunk and going for a drive. Looking down the barrel of a loaded gun....using a straight portland mix. Maybe the last one isn't so bad but it sure isn't great
 
#71 ·
Of course the wall will stand. That's not really the issue. And with a very hard stone like granite it wouldn't be much of a problem for a while. the issue is with the workability of the mix and the incredible unnecessary strength it would achieve without having any ability to flex. Flexing is one of the most important attributes in a masonry wall. Not to mention the incredibly difficult task of re-pointing later in the life of the wall.

I was labouring and had the job of cutting out joints in a cemetery wall built of granite and it turned out an incredibly hard portland type mortar. There were cracks everywhere. The chipper bounced off almost all the joints except the ones that just came out as a unit, stone included. Got out the grinder, the blade was turning red from heat and it was taking forever. Got the chipper back out and it got most of the joint but left a lot on as well. what should have been 4 hrs of chipping turned into 2 days. the wall had been built in the 70's, this was '99.
 
#72 ·
the issue is with the workability of the mix and the incredible unnecessary strength it would achieve without having any ability to flex. Flexing is one of the most important attributes in a masonry wall. Not to mention the incredibly difficult task of re-pointing later in the life of the wall.
Not to mention that a straight portland mix has extremely poor breathablity and traps a lot of moisture that would otherwise wick through a mortar mix.

As it relates to the original question..... the facts are that a straight portland mix is rigid and less moisture permeable then one containing lime and will undoubtedly lead to issues in the future.

I can also attest to the damage that a mix like that does to masonry. The chimneys that I restored in MA were re-pointed using portland cement over the original lime mortar. Evey single joint was cracked, there was trapped moisture and it lead to internal issues. The stone on the chimney overall was a hard basalt but dotted here and there was limestone. Most were in an advanced stage of deterioration..a couple just disintegrated and had to be replaced.

Without a doubt portland has a it's place but the way I understand masonry, you wont catch me using it straight with sand for setting stone. Now, if we are talking pressed concrete work, that's another story!
 
#73 ·
I didn't mean to open a pandora's box here.

I adjusted my mix a little bit today and was pleased with pan life, and workability.

I brought my drum mixer with me instead of hand mixing today, and it made working up a drier batch much easier.

Now hopefully the temps stay up after tomorrow and I can actually get moving on this thing.
 
#75 ·
It's fine with me after hoisting those stones by myself all day.

Plus, right around the third or fourth hand batch I always get impatient and end up with streaks in it :whistling
 
#78 ·
agreed we are going on 4 pages of mixes and why and hows but it still comes down to the majority will not use grout to build a stone wall. some of us use mortar some use lime we all use several buckets and shovels of each. we pretty much all agree straight portland is bad for building but fine for back filling. I will use it when I am doing slip form though.
 
#82 ·
Which one are you on Sean? CJ and I are on the diesel stop...I didn't even know he was on there until a few months ago.

I for one like how different the overall vibe this forum has. Maybe because it's not about a hobby like trucks or whatever but about our profession. I think for the most part, there is great professional courtesy shown here.

Sit, I would enjoy seeing pictures of this rebuild...myself having done a few on early homes and barns.:thumbsup:
 
#89 ·
Ok, I finally snapped some pictures (better late than never huh?)

Like everything else I do I ended up getting pulled away from this job for about a month, finally wrangled up some help and jumped back on it, I am hoping to get the majority of it wrapped up this week, then the house jacker can level the house and I can the top course.

The pictures suck, all I have is an iPod camera, I will rob my wifes camera and get some good ones when it is all pointed up and the floor is poured.



















 
#91 ·
I really wish we had nice rocks to work with, I have tossed out about 1/4 of them so far, mostly big knarly shale lunkers, and lots irregular faced bluestone chunks.

I can't wait to finish this thing up, a day of stacking those rocks feels like two days doing anything else.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top