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kotajack
08-17-2011, 06:03 PM
So you guys seem to have tons of experience and I am looking for the best way to handle the cap stones on a dry lay fieldstone wall. I see the advantage of using mortar just to lock in the cap stones. This is penn fieldstone with differing thickness cap stones

Do you mortar the undersides and leave the joints empty?
Mortar just the joints after all the stone is set in place?
Mortar the joints to the tops or just enough to lock them in place?
Do you guys dye the mortar so that it blends well?

I realize a lot is personal preference but what do you guys find works best for this. Any guidance would be helpfull

Bru75
08-17-2011, 07:18 PM
So you guys seem to have tons of experience and I am looking for the best way to handle the cap stones on a dry lay fieldstone wall. I see the advantage of using mortar just to lock in the cap stones. This is penn fieldstone with differing thickness cap stones

Do you mortar the undersides and leave the joints empty?
Mortar just the joints after all the stone is set in place?
Mortar the joints to the tops or just enough to lock them in place?
Do you guys dye the mortar so that it blends well?

I realize a lot is personal preference but what do you guys find works best for this. Any guidance would be helpfull

I wouldn't recommend any mortar for a dry stacked wall, it will crack and come apart eventually. If you must, use some flexible adhesive.
The traditional method is to use coping stones (see pics) placed vertically, but you will be ok if you dry lay them flat as long as you have large enough stones and they fit well.
Look at the Dry Stone Conservancy website for lots of info. http://www.drystone.org/
The first pic is an old wall that I did some repair work on, the second one I don't think has been touched for a hundred years or more.

FLCthes4:11-12
08-17-2011, 08:51 PM
The mortar is going to crack on a dry lay wall but if you are just using it to help "level out" or even up each stone i think you will be fine. Try taking type s and mixing in a little extra portland and black type N. then scratch the joint so that you cant see much of the mortar the black will make it look like a shadow. but if its more than 1/2 inch thick you need to fit the stones a little tighter. Not sure how your winters are but thats how I have done it here in the south and it works fine.

kotajack
08-17-2011, 09:53 PM
Thanks for the info. Normally I would just set the caps flat and leave them getting the joints as tight as possible knowing that they may move in time but its easy to push them back if needed. In this case I was a bit concearned of kids knocking the cap stones out of place. I was thinking that if I dropped some mortar in between some of the joints it would prevent them from moving if they got kicked or something. I just dont really like the look of the mortar. I did not know if it was the color or just that there was mortar between the joints.

4Russl5
08-17-2011, 11:21 PM
Don't mortar unless you want to encourage the wall to fail faster. Any kind really except for a lime mortar which is really a cushion but not a glue. Your wall if built properly will last centuries without mortar. Have a dry stone waller/mason who is CERTIFIED rebuild the section that needs repairing and make sure they add through stone which will increase the wall strength and last another 25-50 years. Those are two very different walls built by two different masons. I repeat... don't use mortar!
Call the Stone trust in Vermont and get a recomendation for someone in your area to do this for you.

Bru75
08-18-2011, 12:42 AM
Have a dry stone waller/mason who is CERTIFIED rebuild the section that needs repairing and make sure they add through stone which will increase the wall strength and last another 25-50 years. Those are two very different walls built by two different masons.

Are you talking about the pictures? Those are examples I posted of traditional wall capping, I think kotajack is asking about building a new wall.

kotajack
08-18-2011, 08:51 AM
just to clarify, I was talking about a new retaining wall. Most everything around here is mortared walls, but I have seen dry lay walls done different ways. I am most interested in the caps.

I am not looking to stack the caps vertically in this case, although I think that is a very old world look which is cool. Basically all I am talking about is the last row of flat stones that would be laid. I would prefer to leave them loose and just interlock the stones so that the joints are tight, but can you mortar the top stones only just to keep them in place a bit better? The stone that was available on site was not the best and some of the joints are not super tight 3/4". My thinking was just to fill some of the joints that were a bit bigger with mortar to keep the cap stones from moving around, I did not really like the way it looked with mortar but are there any other options besides buying better cap stones?

For the record I have only built a few of these and they were all dry lay, the stone trust in vt looks very interesting and will be doing some time there

4Russl5
08-18-2011, 09:21 AM
Thanks Bru75... you are right. Anew wall is something else and requires more skill. Again the Stone Trust in Vermont does training and certification for dry stone walling to the DSWA of GB standards. KotaJack, the vertical stones are called 'copes or coping'. They sit upon cap stones on top of the wall. They make you wall last much longer by adding more weight to the wall. If you don't do coping stones you need thick heavy caps 3-5" thick. The wall I am building now I am laying 4-5" caps, with 12" coping stones on top, and it is a fence 60' long.

Hands down the best and most complete book for walling is by Alan Brooks & Sean Adcock, titled Dry Stone Walling. Every other book is missing huge chunks or deviates from building methods to standards.

Have fun!