How to Repoint a Stone Foundation | This Old House
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- Опубликовано: 6 авг 2014
- This Old House general contractor Tom Silva saves a crumbling mortared-rock foundation wall. (See below for a shopping list and tools.)
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Shopping List for How to Repoint a Stone Foundation:
- type S masonry mortar
- bonding agent
Tools for How to Repoint a Stone Foundation:
- plant mister
- mason's hammer
- pointed trowel
- soft-bristle brush
- mixing tarp
- mortar hawk
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How to Repoint a Stone Foundation | This Old House
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I use a more lime based mortar , and i keep a bucket of water close so i can dunk every stone and make sure its clean and moist before sticking it in the wall... I love you guy's videos , respect and thank you
Great video , Tom is a real craftsman!!! When I'm pointing up old walls , In some situations where the stone doesnt fit perfectly or i need extra holding power, using the angle grinder with a stone cutting disk , i'll cutting diagonal shollow grooves on the surface of the stone that will come in contact with the mortar, especially if its a large stone like on old stone steps etc... that way it increases the holding power of the mortar...I always enjoy watching Tom do his thing !!!!!
I express my thanks for the video, and providing a list of the tools in the description.
These bots are out of control.
Timeless information. Thank you!
I’m going to repoint our old stone wall outside of the home can’t wait these instructions r simple thank you !
Love these videos presented by "This old house"...
Great help thanks
Brilliant!
Good job
Wicked good vidia, thar!
You should "never ever" use a modern mortar mix that contains any Portland cement. You need to make a lime mortar mix that will be soft, can breathe, and wick moisture. By using modern mortar you may end up cracking your field stones, which are soft. Modern mortar will also not allow the rocks to slightly shift and will not allow the wall to breathe and wick moisture. You will actually trap water inside the wall. I took a lot of time and researched this formula, it's simple, but the only real way to go. You need to pick up a 50 pound bag of NHL 3.5 Lime, one 50 pound bag of washed sharp sand, and one 50 pound bag of washed fine sand. I've read where some people just go with the washed sharp sand. I've been using these items and have got excellent results. The mixture ratio 1 to 3, 1 part lime, three parts sand. I mix mine in small batches using an empty tomato can for measurement. I can lime, 1 1/2 can of washed sharp sand, and 1 1/2 can of fine sand. If using just washed sharp sand, you would go with three cans of sand, one can of lime. After you've measured and poured these ingredients into a large plastic wash tub ie: 16 inches by 16 inches, dry mix them. Then, after you've dry mixed them, add a can of water, mix, then add more water. You "do not" want a soupy mix, what you want is a mix that will hold onto your putty knife blade and will not slide off the blade. A mix that you can pound with your hand, and see the moisture on the surface. Basically, you want to mix it just like a regular brick layer would, you need that kind of consistency. Take a spray bottle full of water and wet down all of the surfaces that the mortar will come in contact with, this is so the rocks will not suck all of the moisture out of the lime mortar mix. Pack the mortar into the voids. I usually carve out two to three inches of loose mortar, you really don't need to go deeper than that. Hope this helps you. I had a very hard time finding NHL lime in Ontario Canada, you folks in the US will find it more readily available. Good idea not to carve out too big of an area at one time. I usually take a two by two square foot area and work it, fill it, then go on to another area further away. This won't stress out or weaken your work area. If you safer working with say a one foot by one foot area, then by all means do that. Take your time, it's fun to see this take shape. Please take great care when mixing and using the mix. Wear the appropriate mask to prevent breathing in Lime dust, proper eyewear and mix using protective rubber gloves. and wear the gloves when applying the lime mortar mix as it can and will, irritate your skin ie: burn. It can take many weeks or months before the lime mortar mix has fully cured. Don't be discouraged if it is still soft weeks after you've applied it. It uses carbon dioxide to cure, just use it and leave it alone.
although it's technically internal, with it being underground/foundations, you would be better using nhl 5 as it's a bit more durable. although I can sympathise with them using cement as most modern specs would never allow lime to be used in foundations
MrNorthernmike thank you I think you're post just saved me from making a big mistake and makes sense. I took screenshots of what you wrote to follow up on. Would the stuff they used be okay for the outside for small surfacing?
Mr Northernmike great article, can you tell me where you found the NHL lime in Ontario?
MrNorthernmike is right. You want to use lime on a stone foundation. It has to breath and move. Besides lime has a stronger bond than cement. Also, the white you see on the inside foundation wall is not paint. It is a pure lime slurry, lime and water brushed on to finish and protect your work.
you are indead correct im a builder in uk so many builders just use cement but it destroys old walls over time. modern building code calls for cement mix underground but that would be with brick that is sub surface (engernering brick) clay brick above ground
Thanks for the video. How do you know if the Quikrete bonding agent is compatible with the mortar?
I've just re-pointed / tucked my entire fieldstone / rubblestone foundation interior using type N mortar pre-mix. I wish I had known about the need for lime/sand mortar. I thought the old sandy stuff was garbage the previous cheap landlord used. Gutters/downspouts are clean/good, and we are going to grade the soil slope properly and put plastic sheet/pea gravel 4 foot moisture barriers around the perimeter. We use dehumidifier and heat basement in winter. Any other thoughts/suggestions?
Amazing nobody chimes in on Bob telling him what he's doing wrong ever. NOBODY?! hahaha
Is there a proper way to face the wire mesh ( not shown in this video) and can you stick tile to morter. I would think it would hold just fine if it holds stones and bricks.
I'm repairing a basement wall ( looks almost tge same as video ) and world like to add tile at the same time
0:17 But it IS rock science...
👏 👏 👏 😑😐
🤣🤣🤣🤣🤣
I’ve got a stone dwelling in the California DESERT where it’s VERY dry and temps rise in summer up to 120 degrees! It’s built by local stones found in the desert sometime around late 1800’s. What should I use? Never done any masonry tuck point work before. Want to be sure to get the right mix.
Wet the stones you are stuffing into the concrete. I've seen another video where the individual made handfuls of mortar and pushed them in manually. Whatever gets the mortar all the way into the holes.
great if you have some one to help mix it
Great tutorial. However I disagree with the use of Type S Mortar. I would recommend use NHL 3-5
at 3:16 , i would dry fit a stone in the bottom triangular part first ,and build up from there . Even when repairing , basic building principals need to be adhered to...
Anyone know where I can get NHL 5 in MA? I have many parts of a 100 year old unknown stone foundation that need repointing. I believe I should be using NHL 5 for that (below grade and load bearing).
I had a mason use Type S in spots on my fieldstone foundation. More than a little upset about that, as he talked about lime the first time he came out and that was the main reason I went with him. The amount of work was also underwhelming for the price, so he's not getting a call back and I'm looking at doing this myself again.
Note to self. Don't start this until the correct mortar is researched and confirmed by an expert. See other comments!
That makes sense. I've been getting conflicting advice on the web (surprise)
James Robinson just the answer I was looking for! I’m in the Hannibal area so now I know what to use. Thanks
At 0:15 he says "it isn't rocket science". Correct! It's rock-it science.
NICE JOB DAD !!!.
he's not your dad jackass
undertoes How do you know
I can't believe someone is recommending a high strength bag mix for a job which should be done with NHL 3.5 lime mortar and sand.
This is crazy. That cement mortar is not the right product for a stone foundation. Should be hydronic lime mortar NHL 3.5 would be fine 5.0 if you want something harder
I should have read this comment first before I posted mine. Thank you for that
It will be a lot easier spraying water with a garden pump sprayer, rather than the little trigger bottle sprayer.
Just have to be safe with the spray.
old rotten mortar .. now its in good shape
I live in Wisconsin and have a stone foundation. Do I still use type S masonry mortar? Also, what brand of bonding agent do I use?
love the video, I have a house that's built in 1850s. There's a section that could use some repair work. but it's on the outside of the house, would this video apply or will I need to add something or do something different to be able to handle rain snow etc?
always talk to your local stone masons union, or bricklayer union. or hell even your local historical society cause each location and climate will effect some of what you need to do
Any tips for redoing an old building built from creek rocks with clay daubed between them? Buidling is an old can house/root cellar.
You should search up Mike Haduck on youtube.
Type S with a little lime added is more than adequate for stone foundation repair. Mortar must be softer than than the units(stone).
Can you then frame over it?.. to have a finished basement?
What would you recommend for the exterior of your home? My house was built in 1926 here in New England. I have a small section under my back entrance door leading into my basement. Could I use this to patch that hole that I found? I couldn’t track where the water was coming in over the winter months seeing that when I had raked up the back yard I had spotting the holes.
Spotted*
Bought a stone home built in 1940. Had the place inspected and all checked out about 2 years when we bought the place her in Montgomery County, Pa. Just this winter after a major storm in bedroom we discovered bubbles behind the paint appearing at the highest part of the interior wall above our headboard near the ceiling. The bubbles eventually started a narrow crack down the wall and into the wall below to the 1st floor. (Just a very small 2" section of bubbled paint.) All the mortar on the stone wall outside was repointed and we just had the roof replaced last summer. I set up my 24 ft ladder up against the exterior stone wall and didn't see ay failing mortar although there are some cracks in the stone. Any suggestions?
I have this problem as well. The main one room house was built around 1900-1920 with additions in 1940 and 1970. The original room sits on softer ground and has settled. The dampness of the cellar has helped to shift half of the main room creating a fine line straight crack up the wall. I was informed the foundation is sturdy, it's just the settling of the home over time. The floor slope has dropped a bit after 2 years of heavy rain 4 years ago. My home was inspected 2 years ago.
what would mike hasuck do ?
I live in Boston and was told by a mason to repoint a fieldstone foundation, it's best to use the following mortar mixture.
Start with a 60 lb. bag of type S....To that....add the following....
1 gallon type N....1 gallon play sand....and 1 gallon of 3.5 hydraulic lime.....Works best in ALL stone applications
Thank you. I live in Mass too. I've been doing a lot of research to figure out a best practice for repairs. There's so much situational information out there when it comes to stucco.
Ok fellow mass folks, I see it’s been a few months since the posts. how is the repointing going? just bought an old house and I thought I’d use the same mix in the video since this old house is mostly filmed close by. But looking at the comments I am not sure what to do. All the rain this past summer is causing hell on my fieldstone basement walls.
Are you the sam Adams guy.. your cuzin from Boston
My basement is similar to this. I keep getting conflicting arguments on which mortar to use. I started using the Type S mortar as is shown in this video but now think that I should be using something softer. I figured that "This Old House" knows what they are doing but I've read that type S is too hard and stiff. Any ideas? What should I use that I can buy from a box store?
www.nps.gov/tps/how-to-preserve/briefs/2-repoint-mortar-joints.htm
I use 3.5 on my stone foundation's & Basements. www.shoplimeworks.us/store/c18/Natural_Hydraulic_Limes.html --- Simple and easy any one can do this. Good luck
Hello gsschneck, it depends on the type of stone in your wall. If it is granite or basalt, those stones are hard and will not expand so Type N is fine. If it is sand stone, limestone/field stone or you are not sure, you can assume the stones will expand and contract with seasonal moisture. That means your mortar should also be able to flex, which means a lime mortar rather than modern portland cement-based mortars (such as type N or S mortar mix). You want to use a lime based mortar which is softer and will flex and breathe as your stone does. It is not as scary as you think, just get Hyrdated or hydorlic lime in a bag from your builders supply store and mix it according to directions with sand (usually 2 parts lime and 3 parts sand) and redo that wall! the good news about the lime mortars is that they stay workable much longer than portland cement, and it is easier to work with (it smears better). Good luck, (I have a 120-year old house so feel your pain). John
To add to my comment: I can't believe they are using type S portland cement-based mortar in the show! It is a concrete and is similar to porcelain in hardness in that it will not give or breathe at all. That is great with cinder block and modern hard bricks, but not soft stone (or older bricks). Type N is a little less hard but still too hard for what looks like a limestone wall. If the stone swells with seasonal moisture -as it is supposed to--and the mortar won't give, the stone can't expand and will be crushed by the way-too-hard cement mortar and will spall out. Another advantage of lime based mortars is that the lime will leach into the adjacent lose mortar and re-consolidate it. It is also alkaline for a long time, causing it to naturally resist mold and mildew. Hope this helps. Good luck, John
Boiled down to basics, hard mortar will form a barrier, water will try to seep through everything else. It's not the mortar and stone/brick's job to hold the water, that's what water barriers (or a drain well) are for.
What happens if the damage extends to the bottom of the wall? If the stones come off is my house being held up something else? We have a section of wall that looks bad but before I try this is the fieldstone holding up the house?
meowmeow, depends if your stone is a just a façade or structural. maintenance of your foundation is important.
Can i put in a standard concrete floor with insulation into a old stone house?. How will it breathe?
Makes it look so easy 😂
It IS easy
I think roger cook said type N so it can have some movement during the winter months. what's anyones thoughts on this?
From what I've found throughout my research, type N 3.5 hydrated lime mixed 1:3 with sand. The wall needs to remain flexible, that's why lime is preferred over Portland cement.
My basement needs to be repointed but i've also noticed that the outside is cracking and might need some work as well. My question is do i need to trench down along the outside of the foundation and repoint the wall or is the underground area ok as is and i should just work on the above ground area?
I use 3.5 on my stone foundation's & Basements. www.shoplimeworks.us/store/c18/Natural_Hydraulic_Limes.html --- Simple and easy any one can do this. Mix 2 parts washed Mason sand to one part Hydraulic lime - like a play dough - let sit for 15 min and shove in cracks. check out the videos from England on using a stiff brush to pack in the mortar tightly. Good luck
smm0 ,
I’ve been researching fieldstone foundations lately and, if this is what you have, then no you don’t have to dig out the soil against the outside far of the wall to point it. In fact you’d cause more trouble to do that since the soil that’s currently packed in there now is best left undisturbed; when these houses were built, it seems the accepted method was to dig down, then pack your foundation-stones up against the earth-wall, and point (or mortar) from the inside up, and on the outside only above the level of the ground. Also many of the comments indicating lime-only mortars (no Portland cement products) are spot on, Portland based products are showing to cause more severe damage by holding accumulated moisture against the rocks; Portland wasn’t developed at the time these style homes were built. They used Lyme which has different properties, and repairs are best done with Lyme.
Our American colonial stone house [started 1750s] basement was flooding uncontrollably and had increased gradually in severity over the decades. Stone is a sandstone type, reds, greens, yellows, lots of limestone in our area. After discussing with experienced stone masons in the County [learned from the very old timers] I was told that digging all the way down to the footers of the stone foundation was the only way to start.
Yes the concern is valid for disturbing earth and its tiny pathways, that hadn't been touched since the 1750s. The clay soil here heaves in the winter and gets screwy for sure, so pulling out all that settled earth could create other issues.
But there was no way to keep the water out - you must create a barrier on the OUTSIDE. A barrier on the inside of the foundation would allow the rocks and mortar to soak up water from the outside, and possibly create a truly failing wall eventually.
This area has a very high water table. Originally up to the 70s, houses here had no basements. They would have been indoor swimming pools. Our basement would not have been completely dug out originally. As methods were discovered for drier basements, basements started showing up in houses aaaaaaand people started digging out earthen basements in very old houses. Eventually those situations became very wet. SO to fix all that, you really have to start from the outside and protect the outside walls under the earth from water penetration.
Additionally, this is "dry wall" or walls without any mortar. Field stone here is not cut but fitted together [freaking spacial geniuses!] so there is no mortar on the inside of these walls to keep water [or vermin] out. The pointing on the outside, the mortar, acts as a seal but isn't the stabilizing glue - the stones themselves are that well fitted!
Here the foundation was dug out, a big wide trench all around, all the way down to the first course of stone. Wide enough for two men to work together too. [yea i hated seeing the sturdy house so vulnerable down to its foundation, but it stood still and everything stayed put - the stone walls are two feet thick at the base and the walls get less thick, narrowing as they rise]. A bobcat reached down to dig the trench with men using shovels to finesse the shape.
The walls were cleaned up as much as possible.
First to go in was a French Drain wrapped in landscaper fabric to keep it from filling with debris. Covered.
After ensuring the pre-existing mortar was solid, the cleaned walls were parged with a cement-like coating. Then a black water proof coating over that. Then boards with holes to keep the dirt off the walls.
After a few weeks to cure, dirt was replaced partially covering the new work, allowed to settle, and filled in more. Once the settling seemed to stop, the last layer was dumped in and grass sown.
the work is two years old now and the basement has been dry. The water continued to seep in as long as the dirt was not completely filled in or until grass was sown. Additionally, a trench [swale] was created to divert any other water from approaching the house.
So yea, to create a dry basement in a very wet environment including a very high, close-to-the-surface water table, sealing the outside of the foundation down to the buried footers worked.
The work was done on two sides of the foundation, since the house sits on a hillside with the other two sides exposed.
We also had the entire house exterior re-pointed using a limestone mortar which flexes and breathes with the stone. Hard mortar will kill stone around here - the stones will chip and eventually crumble if cement-style mortar is used FYI.
I think that hydraulic lime or None hydraulic lime it´s the same think. Because in the second exemple, you will have to put it one water before you use it (carbon dioxide and it burns.. burns your hands, your eyes, burns your lungs... When you put water ). And you sould do it one month before you use it, and it turns into the same: - hydraulic lime. The problem of hydraulic lime is that it drys to fast when using it. And also it dosen´t give you a very strong mortar mix. Its week. But its good for allowing the wall to breathe, specialy if its a wall in contact with the earth or a may be a fundation. I think that if you mix Portland Ciment with sand and earth, you will have a better motar mix and you be able to make the wall to breathe.... But if you Portland Ciment and Sand betwne the stone... you will have necessarally to isolate the out side of the wall with PVC Plastic drain wall.
Can anyone recommend the right type of cement that I can buy in the store to hold my old brick foundation together? I am not going to tuck point per se but want to spread something over the bricks to have sort of a smooth look. Hoping it's something I can find at Home Depot or Lowes.
@@jamesrobinson7910 m
Was S with Portland the right choice? Won't that be harder than the stone?
type S is mortar with portland. in new england where they are, this is what they use, i am in new england and you relaly need the portland or the winters will cause that to crack and break away.
I can't believe how he's made that mix 😂
Applying super glue mix little a bit here and a little there nice bad job you cowboy.
Could I do this a my house if I find a good contractor .
Self do.
He is creating a bandage ! 3-4 years … bam! All those rocks are down !
Can anyone tell me what type of brush he uses at the end of the video to get the mortar to flow nicely against the stone? Many Thanks.
It's an asphalt brush ( I've also heard it called a Mason's Brush) www.lowes.com/pd/Marshalltown-7-in-x-12-in-Tampico-Fibers-Asphalt-Brush/1000101925?cm_mmc=shp-_-c-_-prd-_-tol-_-google-_-lia-_-217-_-hardsurfacetools-_-1000101925-_-0&store_code=1637&placeholder=null&gclid=Cj0KCQjwupD4BRD4ARIsABJMmZ_zuMuTxvrmGYp8Kjpt6Ci4i2aGxMs85IV0xhFh7BhjUGA90Raw5BoaAkHGEALw_wcB&gclsrc=aw.ds
One with bristles
some call it a dash brush. it can be used to apply water, stucco type finishes, whitewash, etc. They may be with the masonry supplies, or paint and roofing things
Would anyone know if is possible to find a contractor to do this to an old house in northern Wyoming?
Were finishing one in southdakota now then we could
Houses in New England are a pain to maintain period
Throw tha moetah in the crahcks.
first spray it with woetah
Wouldn't a piping bag be good to use? I bought one, but I don't see it being used much...what gives? Ty
Piping bag is fine to use, just depends on the situation and consistency of the mortar. If the mortar is too dry (sometimes it needs to be on the drier side), a piping bag doesn't work well.
I thought the same thing about using a bag but it's about the consistency of the mortar
Should have used lime mortar, Wally!
Quikrete on a stone foundation? No way. Use Lime and sand or the rocks will decay.
Is this okay even on a load-bearing foundation wall? What about if it's out to the edge/corner where a door has been cut through it and they are crumbling at the slightest touch, are with large stones falling down to the ground? (House is 133 yrs old). A structural engineer just told me I need to replace the whole thing. I think if I were to start brushing on it like you do in the video to clear out the mortar the whole thing would crumble and maybe the house would fall on top of me.
wouldn't it make sense to try a powerwasher to blast out the old mortar?
That's what I did, carefully
I'm just curious should that not be a sand and limestone type of mortar? We had an engineer here for the same issues and he told us that we needed a sand and Limestone mortar as a because the concrete type stuff will not be as flexible the original stuff was like a sand and limestone mix. Any help would be great thanks
Poor concrete-sand mixtures (1-9), behave pretty much like lime-sand (1-3). And it's way cheaper.
@@carlosbah4623 yeah but is there that much cost difference just for my own house? I'm doing it myself? I mean if the historical products and Manor is available should I not use that? Again I'm just double-checking everything before I put one thing or the other.
If your foundation was originally lime mortar you should use lime mortar - no portland at all
It’s always nice to watch This Old House but it would really help if they used a life like situation because if my walls looked that good I would be lucky. I’ve never seen your show go to someone’s house who really needs the work and help you either go to famous people or famous old houses and show us the repair that we can figure out or watch a regular person fix.
Yeah exactly. I just bought a house built in 1868 with a stone foundation and was looking for repair tips and just about everything from this guy is useless.
how is shuving all the crevices full of cement going to make the foundation any stronger ...it might make it look better but i dont see it helping the the structure
Lol that's how it was made the first time
@@lawrencegray5403 Wrong it was shoved full of earth & lime mortar
,👏👏👏👏👏👏😊
why not use lime mortar
Interesting and very informative video, and also comments. Now, were I to use type N, would that be a compromise mid-point between NHL and type-S? Some what best of both worlds since the objective is to keep the internal weight-bearing aggregate stable, not necessarily to be full type-S weight bearing by itself; hence appeasing though who commented upon the strength of field stone not being enough for type-S mortar. As for plastering over the entire wall, I cringed, though perhaps incorrectly. Does the commenter mean, Plaster over the entire wall prior to repairing, or Plaster over the entire wall after repairing? I see plastering over the entire wall prior to repairing as a "drop ceiling" job, and plastering over the entire wall after repairing as inhibiting the porosity of the existing stones. Either way, I do not understand, so please add a bit more detail.
Comments welcome.....
@@jamesrobinson7910 Which would you recommend for those of us in St Louis?
I like to spray chicken grease for dust control
No Tommy! Not Type "S"!
How old is your home, when was the mortar put in ,do you Guarantee it will last another hundred years what is the life expectancy of a rock foundation if you don’t know where would I look to find that out???? My whole shoes hotter than 25 years old some of it has rock foundation
gunner, you have to think of it this way,. the video talks about repairing a stone foundation built over 100 years ago. Most of the houses currently being built won't last that long with modern materials.
Mix it up in the taaaap....
Its TAAAHHHPPP
grab a conner of the top?
Tarp lol
Type S is for structural people! There's a lot of weight on that wall, and S is the way to go. If it was Brick you would use an N
I do floorsanding and epoxy garage floors, someone just asked if I could fix a basement like this because they were quoted $120,000. I said I think I can be done for about $2,000 and they laughed
god got cold air pouring in in winter from these walls....and it gets -20
People like Tom Silva are what keep professional masons like myself in work!! 90% of our work as Historic Masonry repair specialists, is removing the wrong mortar, Like the S type used above and replacing it with the correct mortar which is a 3'5 NHL natural hydraulic lime mix. You only have to research for yourselves, the Secretary of the Interior's Standards for the rehabilitation of Historic buildings and monuments, to see just how appalling are the instructions that Tom is giving out to the world. Tom, I've been doing this since 1966, you should have better researched this subject before pontificating about something you know absolutely nothing about.!!
your to old to be on RUclips beat it old fart
Curious, what's the benefit of using the mortar that you are suggesting?
@@BigScreenLife Stone foundations like the example above, were built in the 1700's and 1800's through to the early 1900's, using a variety of ingredients in the mortar. The binder used in the USA was usually a crushed and cooked limestone. When mixed with sand/crushed oyster shell/ground brick etc, and water, it made a mortar capable of supporting the stone or brick that was being used at the time. Sometimes in the 1700's, before quarrying took hold in the USA, they would add stiff clays to the mix, for walls that were not going to be seen once built, i.e. foundations, jails, etc. The last working limestone kiln in the USA closed in 2008. The material used mostly in modern times, that closely emulates the lime mortar of yesteryear is a Natural Hydraulic lime, (NHL). Portland cement based mortars are never to be used in place of lime mortars. There is a chemical reaction between the two that results in catastrophic failure of the Portland mortar. Portland was used by American masons in the 1960's through to the early 2000's before anyone realized the damage it was causing to many of the nation's historic buildings and monuments. Portland cements are good for modern brick and CMU constructions, that are made to withstand its st5rength. However, it is far too brittle and strong to use on buildings built before the 1930's. Portland cements are the number one cause of spalling brick faces on old buildings. Water is the second. Stone foundations move constantly as the earth around them goes through the 4 seasons. Dry laid foundations and walls are built in such a way to accommodate that movement. Stone foundations built with lime mortars flex, and the best thing about NHL mortars is that they flex with the stone/brick. It's also capable of healing itself when small cracks appear in the surface due to the movement of the building. Mortars are there to act as a cushion, not as a glue. As I said above, look up the Secretary of the Interior's standards for the rehabilitation and repair of historic buildings, you'll see the recommendations are to use like for like materials when repairing/restoring, rehabilitating old and historic buildings and monuments. Two other things I would also point out regarding the above video. You should always wear a mask when removing old mortars from joints, always. OSHA standards require you to have vacuum equipment at the end of a grinder to remove silica dust from the air. You should always wear safety glasses when removing old mortar, whether you use a scraper or a hammer and chisel. Once again, do not put Portland cement based mortars over a lime based mortar....ever!!
@@keithboyd1157 agreed. Cement based mortar not only does not bond with original sand mortars it actually makes it worse as it starts eating into the sand based mortar.
Look up Mike Haddock. Basically he would agree for restoration of old buildings, but to use that mortar in the north with freezing and thawing would be foolish. Type S or Type N ONLY up here unless you want to keep calling the 'professionals' every other year to fix falling apart structures
He should be using Type N, not type S mortar
He wouldn't touch my stone foundation with a 10' pole.
Use a 5 foot pole then
Cement! To point a stone wall!!..how unprofessional and damaging is that!!! Should be a 3.5 lime mortar!!
When does the mortar look fade back to a natural look?
after it cures.
He used the wrong type of mortar - should have been a lime mortar. So many "professionals" have no clue about the need to use lime mortar when replacing lime mortar. Disappointing that Tom Silva didn't know this - but he is a carpenter not a mason.
Where are tier masks? Prob not good to breathe that in no?
no gloves?
2 or 3 inches? Bad.
Is the to much or not enough?
If this is infact an instructional video, what is his objection to wearing work gloves and a cheap breathing respirator. I mean at least show the safest way to perform the project. If someone chooses not to wear these items, that's their option. At least they would have been shown the safer way.
he has concrete dust all over his hands like it's nothing and - doesn't care about breathing in all that dust, you can't even really do a big project and not use gloves. I mean...
Thanks Karen.