I have a hundred plus year old home an interior wall has soft spots on the wall some are 2 foot in dia. What causes this I am a cement mason so I know I can fix it but I need to know why it is happening?

Taking a wild guess here but possible water infiltration? As in you have a small leak somewhere.

Well smoothy that's just it I have a new roof on the house which is a story and a half with no plumbing upstairs! The wall I am speaking of has no plumbing in it under it or near it! I'm not an idoit! This is why I asked if anyone knew what it could be.

If you missed the last part on my Q, I am a member of OPCMIA that stands for operative plasters, cement masons international association of Indiana so thans for the water damage anyone have a better answer

well smoothy thats just it i have a new roof on the house which is a story and a half with no plumbing upstairs! the wall i am speaking of has no plumbing in it under it or near it! im not an idoit! this is why i asked if anyone knew what it could be. but thanks for your brillianceYou know... you can tone down the attitude more than a few notches. Ask a roofer if new roofs can leak... 100% of them will say yes, mistakes can be made. And it only takes a small leak to dampen plaster (not saturate it) to do that. And you do know... it doesn't have to even be the roof leaking, It can be a wall and water CAN travel to the opposite side of the house before you even see a symptom.

I never claimed that's the ONLY cause... but a possible one. Assuming it NOT something has a way of burning you in the business world where time is money.

Water could be entering through siding or window that is not sealed correctly.

The lathe may be pulling away from the brown coat. This can also give u soft spots.

Chuck

You know what assuming does then right! Sorry for jumping your answer! Its not water damage I'm sure of that I have been up and down in and out and all around this house! I have also have others do the same, that was my first guess has to be water damage. This is why I am asking for help I thought it could be moister from the basement but its dry and I have a water barrier on the floor joists. And the spots are here and there hit and miss if you know what I mean! And none of the other walls or ceiling

creahands thanks but it is in the center of my house no windows or siding or anything! Thanks though

creahands why would it be pulling away from the lathe? Just old product? Or do you think its something more like structural?

Ryan, as you can see, smoothy has a very good reputation here.

I also have done a lot of drywall and plaster work myself. Moisture (coming from somewhere) is pretty much the only reason that plaster will become soft. With age alone, the opposite happens: it gets dry and crumbly.

If it's getting soft, then you probably have moisture getting to it.

Ryan, as you can see, smoothy has a very good reputation here.

I also have done a lot of drywall and plaster work myself. Moisture (coming from somewhere) is pretty much the only reason that plaster will become soft. With age alone, the opposite happens: it gets dry and crumbly.

If it's getting soft, then you probably have moisture getting to it.

I know what I'm talking about and I don't think that my response was unjust where I'm from that kind of thing don't go over well! And his reputation is only as good as his last word you know what I'm saying? And I even said sorry!! I'm not an idiot my first thought was water but believe me there is no moisture and it is crumbly once it is broke loose I have had inspectors and roofers and everyone and there brother here. Thank you so much for your time in my problem!!

Hi Ryan

Is this an inside wall?

Is it a bearing wall?

Do u have balloon framing?

The brown coat which is under plaster finish locks into the lathe. If the locking key of brown coat breaks off because of movement of lathe or studs. This can cause the spongy effect u are getting.

If u open up an area, u may see that brown coat has pulled away from lathe.

The only solution is to remove loose area and redo.

Had house that was built in 1897. I replaced the areas with sheetrock.

Chuck

it is crumbly once it is broke loose

Crumbly is not the same thing as soft.

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