Cracks in the plaster

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1

Originally Posted By: kluce
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I went on an inspection this morning to a house that was built in 1923. It had plaster walls. At every window I found a crack started at each corner running to the ceiling and to the floor. It looks like it’s never been patched and there were no cracks at the ceiling. The windows were replaced about 5 years ago. The homeowner only lived there for 4 years. I think the cracks were formed when they installed the new windows and that is why they were never repaired but I would like your professional opinion. icon_wink.gif


Nothing visually told me anything else.

2

Originally Posted By: roconnor
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I would be willing to “bet the ranch” that the cracks ran at an angle off the window. Pretty typical indication of some minor house movement/settlement.


If the cracks are not too bad and look old, with no other signs of recent movements/settlement (windows/doors sticking, foundation cracks, ceiling cracks, etc) then in my mind that alone is not a big deal. Most homes will move and shrink a little when first constructed, before they "settle" in and find a happy place to be ... ![icon_lol.gif](upload://zEgbBCXRskkCTwEux7Bi20ZySza.gif)

If you are worried or not sure, you can recommend monitoring by having the owner jamb a toothpick in the crack (not foolproof, but sometimes helpful) ... if it falls out on its own it might be a good idea to have an engineer check things out.

--
Robert O'Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee

I am absolutely amazed sometimes by how much thought goes into doing things wrong

3

Originally Posted By: rhinck
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Kevin,


I Dido what has already been said and would add using a lightweight spackling across a crack as a monitor.

Also full coat plaster jobs should have a section of expanded wire mesh nailed diagonally across all four corners prior to the installation of the plaster. Possibly this was omitted- just a thought

Rick

4

Originally Posted By: kluce
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Not worried about the cracks. Just never seen this before. The cracks look like they went up and down with the 2 by 4.

5

Originally Posted By: roconnor
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Well I just lost my “ranch” … icon_eek.gif


If its old vertical cracks on plaster then its probably just plaster shrinkage cracks. If there is a little too much moisture in the mix, then the plaster will shrink and produce minor cracks at the weakest point ... bingo, the window and doors.

That would be my guess without seeing it.

--
Robert O'Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee

I am absolutely amazed sometimes by how much thought goes into doing things wrong

6

Originally Posted By: dvalley
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Whenever I see cracks above windows and doors, I tell my client that it is nothing to worry about. (unless of course it continues into the ceiling or floor).


As Robert says, shrinkage was the cause of this most of the time. This occurs at the corner areas diagonally because this area is the weakest point of the wall.

–
David Valley


MAB Member


Massachusetts Certified Home Inspections
http://www.masscertified.com

"Some cause happiness wherever they go; others, whenever they go."
7

Originally Posted By: dfrend
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When I went through bulding school for the insurance inspection industry, this was termed “settlement cracks”. It is a very common claim for payment. It is NOT covered by the way as it is a fairly normal event and not Accidental Direct Physical Loss(ADPL).


The following is a quote from the National Park Service info on plaster.

Quote:
Overloading. Stresses within a wall, or acting on the house as a whole, can create stress cracks. Appearing as diagonal lines in a wall, stress cracks usually start at a door or window frame, but they can appear anywhere in the wall, with seemingly random starting points .



The entire article can be read at:
http://www2.cr.nps.gov/tps/briefs/brief21.htm

--
Daniel R Frend
www.nachifoundation.org
The Home Inspector Store
www.homeinspectorstore.com
8

Originally Posted By: roconnor
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kluce wrote:
... The cracks look like they went up and down with the 2 by 4.


As long as there were no other indications of settlement, looks like it might just be plaster shrinkage.

--
Robert O'Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee

I am absolutely amazed sometimes by how much thought goes into doing things wrong
9

Originally Posted By: rpalac
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Hi Guy’s,


I hope this helps.


I am not an engineer, I do go to engineering school but more so my years of asking questions and rehabbing old house might have some answers for this question.


Very often people tend to blame a lot on settlement. It's almost as diverse as blaming fires on electrical. Seems to be the scape goat answer or the easiest to ball park with. Although it is not all that incorrect it does go much deeper.

With regard to settlement....EVERY building has some form of settlement. This is normal. The caution is when it is uneven. Such as unstable soil against stable soil.

In this case I would bet the ranch (hopefully someone else's), that this is an inherent problem two fold.

1.) The material used being horse hair fiber stucco...very common back then, is a brittle non-pliable product. Our industry has moved toward the modern drywall to do away with this surface cracking and time/labor intensive product. As we moved forward from the early 1900's when plaster was common. It was discovered we can make a product called concrete board. It came in 2 foot by 2 foot sheets with cardboard paper on both sides. This was used around the late 40' early 50's. It was the beginning of speed for the installation and the fact that the cardboard cover hid the tiny fissure cracks in the plaster. The product was very heavy and the cardboard had a tendency to bubble back then. Shortly later the concrete slurry was replaced with a slurry of plaster and then eventually gypsum. The cardboard sheet was also later chemically processes to what we have now. The reason for the carboard like sheetface on drywall is for adhesion and to hide the tiny fissure cracks on the inside.

So the cracks in plaster are very normal. BUT THERE STILL IS ANOTHER REASON WHY THEY APPEAR AT THE CORNER OF WINDOWS AND DOORS>

Here is the next part
2.) Yes, some of this is form settlement....but it is more so the expansion and contraction of materials. As the building breathes these non-pliable areas cannot all expand and contract at the same rate. in addition joint areas tend to open and close due to angular surface movement of expanasion displacement.................This only produces some cracking usually slight.

DOOR's and WINDOWS are surface interruptions of expansion and contraction and it is evident with what is know as webbing in the contributor is vibration. Each time you close a door or open a window you create vibration much like a percussion instrument. The vibration in conjunction with expansion contraction movement and the interruption of surface area caused these cracks to appear at the corners like spider web's.

In commercial construction with masonry walls the block course next to ALL door openings MUST be filled solid with mortar to help dampen this vibration factor. If you go to a masonry building and see a crack surrounding the entire steel door frame about six inches away this is a good example of how door slam vibration eventually creates these cracks.


All-in-all ...this is normal and just a result of time and the material they used.


Boy was that lengthy and boring....sorry guy's
(ps... I hope you got the ranch back)

Bob

10

Originally Posted By: Mike Parks
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Also remember that lumber, if too damp, will shrink.


Try a flooring adhesive in the cracks. It will "give" more than mud.

I do not like the word settling. It implies that the home is sinking.

I just address the cracks and use the word shrinkage instead. Unless however the problem is in the foundation. That is a different animal.

Mike P.

11

Originally Posted By: Bill
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Robert, that is probably one of the most articulate explanations I have ever heard. Fantastic job! If I may add though. If there is any exposed framing in a home such as garages or basements, often when the framing is done you can see gaps in framing members around the headers of openings such as between jack studs and the ends of the headers, I believe these also contribute to “settling” that many folks talk about. I feel that if more care was taken during the framing phase, a lot of settling would not take place.

12

Originally Posted By: rpalac
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My haste to explain is unfortunately an opportunity for me to slip the wrong words in and confuse the issue…


Many times when WE speak about settlement, WE either are referring to settlement and stress or stress or just settlement. They are different animals and at the same time they are related.

(Here we go...ranting and raving over words and how to use them....Hell, I have trouble ordering a cheeses burger and fries at the drive thru.)

Well, it is a circle than does become very entwined but in the original question and description I would say those cracks are more likely from common non-concerning material stresses.

Does that make sense?

Settlement is shifting or settling of materials as a whole or part of.

Stress is the flexing or shrinking or movement of materials Like when a 2x4 dries out and shrinks it causes minor stress on it's associated materials.
When the temperature changes and dissimilar materials move, expand, contract etc. at different rates, this is stress and not settlement.

ON THE OTHER HAND AS TIME GOES ON WE SEE BOTH OF THESE HAPPENING OVER, AND OVER AND CREATING EVER SLIGHT MOVEMENT AND WE CALL THIS AS THE BUILDING BREATHES.

But older materials are not pliable and as a result we see imperfections.

CRACKS!
Now, When a big fat guy like myself try's to fix these CRACK's. We often wear shirts that are to short to cover our big gut. When we bend over we present a new problem..."Plumbers CRACK". This is a very different and dangerous issue. One of these can ruin your whole day!

However, if you are exposed to "Plumbers CRACK", do not try to hide it and at the same time do not put this on the repair report.
No, It is not being evasive, however there are some things by code that we just have to accept.
What ever you do don not attempt to fill it with caulk.
(If you do, Please get it on video for us to see)

Plumbers Crack unlike otheres creats stress and is an form of over settleing loads.

There is a lot about plumbers crack that has not been written yet but I asume it is only due to the WIDE SPREAD and unrearched VIEWS of so many. Suprising isn't it.

Do we have a THREAD pertaining to PlumbersCRACK?


A confused Bob

13

Originally Posted By: dbroad
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Take it from a Professional Plaster of 25 years. If you say the cracks ran straight up with the 2X4s then its due to the bad lath behind the plaster. A 45 degree angle of lath should be ran at all corners. It also should be pictured framed with lath, however many times people just run the lath to the window and straight up, then lath over the window. Causing a vertical crack every time they do this. A straight brake in the lath means a straight crack in plaster.Settlement cracks will be at an angle up the wall.