1790 Stone House Interior Walls no Mortar Behind Plaster… just dirt

[USSTONEHOUSE]

Hello everyone, I’m in the US, I have what we call an old house here (1790) we are taking the plaster off the stone to check the condition and then plan to re-plaster. When we took the plaster off, we noticed there was no mortar between the stones just dirt falling out. We are concerned about the structural integrity of continuing this project as we’ve never owned old house older than 1970, I need some advice. The larger stones don’t budge if I give them a shake, but the smaller stones will fall out, feels like a game of Jenga. Now I know that the plaster was not structural and it wasn’t holding up the stone for all this time, but I am concerned that a small stone may come out and then create a ripple effect and drop a large stones. Any advice or help anyone can give me would be much appreciated.

 

[aockenden]

Welcome, nice to see a fellow American (although I now live in Wales). And also wonderful to see a proper stone house in the US!

What you’re dealing with are typical jitters for new stone-house owners. I was the same. One thing nobody bothered to explain to me (including about 100 “expert” builders) is that the “dirt” you see coming out from between the stones likely IS the original bedding mortar used when building the walls originally. And subsoils typically make excellent bedding mortar! Combinations of clay, sand and natural fibers have held together human buildings since the beginning of time.

Now regarding little pieces of that bedding mortar and small stones falling out of the wall, this is also normal when stripping all the way back to stone, but you should proceed with appropriate care and caution. Basically in preparation for replastering (hopefully with lime or clay plaster), you should simply vacuum out any dry dusty debris from the wall, then spray the wall down and just roughly repoint the joints between the stones (preferably with lime mortar) to help stabilize everything. Let this harden for a couple weeks and then proceed with replastering.

 

[aockenden]

Here’s some pics of one of our walls stripped back to bare stone (bedded on subsoil mortar) before and after a rough repointing, and then during base coat plastering with an insulating lime plaster. Before the repointing there were tons of loose / wiggly stones. Once it was roughly repointed it all immediately feels rock solid.

 

[USSTONEHOUSE]

Thank you so much for taking some of this worry away. I can see what you are talking about with your home, it does look like dirt in between but I guess after 234 years it’s just not what it was. What do you spray the walls with? Again, appreciate you taking the time to ease my nerves. Here is a photo of the front of the home. It’s a great house! I’m really glad I found this forum, do you recommend any other resources for old stone homeowners? Trying to make sure I have the information I need to properly care for this home.

 

[aockenden]

Thank you so much for taking some of this worry away. I can see what you are talking about with your home, it does look like dirt in between but I guess after 234 years it’s just not what it was. What do you spray the walls with? Again, appreciate you taking the time to ease my nerves. Here is a photo of the front of the home. It’s a great house! I’m really glad I found this forum, do you recommend any other resources for old stone homeowners? Trying to make sure I have the information I need to properly care for this home. View attachment 14834

Excellent, beautiful home. You spray the walls with water to soak up the dust in the wall immediately prior to re-plastering. No offense but that question indicates that you’re really early in your journey to understanding old houses. You should buy the book “Clay and Lime Renders Plasters and Paints” and read it from cover to cover before proceeding with any major works. It will get your head on straight about what is going on with materials and approaches in old homes.

 

[USSTONEHOUSE]

Yes, you are absolutely right - very early in my journey, no offense taken at all. I will get my hands on the book as soon as possible and begin reading. Thank you again for your help.

 

[Cubist]

Welcome, nice to see a fellow American

Yikes - I'd best check my recent posts to see if I've chucked an insult in a too Westerly direction. Question - how far West do I need to be concerned about?

 

[aockenden]

Yikes - I'd best check my recent posts to see if I've chucked an insult in a too Westerly direction. Question - how far West do I need to be concerned about?

Haha I have seen some comments but no offense taken. Minnesota is where I’m originally from.

 

[USSTONEHOUSE]

I would say anything west of California and you’re okay

 

[Cubist]

Minnesota is where I’m originally from.

Bugger! That's two blokes from that State I've carelessly trifled with. The other was a 6 foot 19 inch ex ice hockey player who was my immediate boss here in the UK one time and used to scare the hell out of the local security team. Despite my somewhat less commanding stature our voices, attitudes to life and manner of speaking were very alike and, if unseen but heard, we would sometimes be confused for each other. This I was told led to our being given what was claimed to be an affectionate joint nickname after some found our mutual growling/barking at each other across a conference table quite amusing.

As I tend to keep a rough count of the places I may be unwelcome that is now, sadly, a double hit on Minnesota and my scores for the rest of the US are roughly as follows;
New York - > 5
Washington DC - > 10
Boston - 1
Philadelphia - 3
Miami - 1
Birmingham Alabama - 2
Los Vegas - 1 (I offended a young lady by not knowing the local differentiation between a secretary and a stenographer).
Kansas City - 1
Chicago - 2
Dallas - 1
Plano - > 5 (Plus 1 for a cop who was nearly as scared as I was when a hand gun fell out of a glovebox during a traffic stop).
Los Angeles - 2
San Diego - > 5
San Francisco - 1
Seattle - 1

I think there may be a few others too as I've discounted smaller towns and naturally haven't included Canada.

I would say anything west of California and you’re okay

Nope, too late.

Hawaii - 1 (I managed to upset a tour guide during a visit to the National Park - he didn't quite get the irony intended in my grumble about not be allowed closer to the volcano)

Further West there would be more additions to this list.

But please don't read too much into this, I'm just as unwelcome on 6 of the other continents I've worked on/visited and theres no truth in the rumour that local populations start shooting at each other after I apply for a visa. But, questions were asked when two of them did.

Now, how can I upset a penguin to make it 7 out of 7.

 

[Cubist]

USSTONEHOUSE

Dammit, hopefully you've never commuted to work in DC anytime in the last 20-30 years?

 

[Marian]

Hello everyone, I’m in the US, I have what we call an old house here (1790) we are taking the plaster off the stone to check the condition and then plan to re-plaster. When we took the plaster off, we noticed there was no mortar between the stones just dirt falling out. We are concerned about the structural integrity of continuing this project as we’ve never owned old house older than 1970, I need some advice. The larger stones don’t budge if I give them a shake, but the smaller stones will fall out, feels like a game of Jenga. Now I know that the plaster was not structural and it wasn’t holding up the stone for all this time, but I am concerned that a small stone may come out and then create a ripple effect and drop a large stones. Any advice or help anyone can give me would be much appreciated.

View attachment 14827

View attachment 14828

hi! looks just like my 1800ish rubble built Welsh house, just stripped back to be restored with lime. I agree, I found it a terrifying sight, but fortunately have a reassuring restorer. Turns out the truly alarming bits of work are all from the last 30 years!