Stone Foundation Cracks, Bulges, Movement

How to Recognize, Diagnose & Repair
Foundation Damage,

Introducing Stone Foundation Damage

Of these stone foundation damage cases, roof spillage by the foundation is most-often the prime source of damage.

Particularly in a freezing climate the force exerted by freezing wet soil against a foundation wall is tremendous.

Stone foundation walls on pre-1900 buildings are often quite thick, up to four feet at their base.

In their original design these walls tolerated water in the outside soils by permitting it to seep through the wall and often to drain away through a dirt floor or even a through-wall drain in a low corner.

But more modern modifiations to such buildings included central heating, efforts to dry out wet basements, and other changes that in turn changed how these buildings worked. Some of these changes actually increased the risk of later foundation damage from water or frost.

The stone and brick foundation shown below is common in older buildings, in this case a church in Staatsburgh, New York.

In this photograph we see a combination of stone and brick foundation wall.

Brick was often laid in finish courses atop a stone foundation wall. In other buildings the entire building wall wall may be of stone except that bricks were been used around windows and doors to give a more square opening. That detail made wood framing in of windows and doors easier.

The basement and its adjoining crawl space of this Staaatsburgh New York builoding had suffered a long history of flooding and an occasional sewage backup too.

Stone walls, like other masonry walls, are often damaged by water and frost, especially where roof spillage splashes close to the foundation wall.

Below we see a bulged stone foundation wall that abuts a more square wall (at left) in better condition and probably of a younger age and by a different mason.

Such dry-laid structural stone foundation walls rarely fail by leaning but are often found bulged or damaged by water, frost, vehicle traffic, or by modification by the building owner.

In this photo the mortar, probably a soft lime and sand mix, has washed out of stones at this inside corner of the building foundation where the corner is below a roof valley - a source of frequent spillage during rain and melting snow.

Below our photograph shows the futility of trying to keep out water by applying mortar to the inside of an old stone wall.

Near the entering water pipe at the right side of this photo we see ice forming in this wet basement, perhaps because lots of surface and subsurface runoff are being caught and directed towards the foundation wall by the trench dug to install the new water line.

So much of this wall is wet over so much of its height that we can be sure that roof spillage and surface water are entering the building.

Beware of old dry-laid stone foundation walls which were later made "water proof" by mortar or by casting an inside thin veneer of concrete against the stone.

Watch out: People often used lime or cement to point up the gaps between the stones in such a wall as an attempt to reduce water entry or to try to keep out vermin. I

But if this change is made without also taking steps outside to keep water away from the building, frost and water damage to the wall may actuallyt be more likely to occur as water becomes trapped within the wall's structure.

Common Stone Foundation Wall or Stone Structure Defects

This sketch of the components of a preserved stone foundation with a solid masonry exterior wall is courtesy of Carson Dunlop Associates, a Toronto home inspection, education & report writing tool company [ carsondunlop.com ].

Photo above: loose, dislocated stones in a building foundation, courtesy of InspectApedia.com reader Jennifer.

• Dislocations and loose stones
  
  commonly at building walls and corners above grade where exposed to splashing roof runoff.

Photo above: buckled stone foundation wall, photo courtesy of David Grudzinski, discussed in detail at FROST PUSH & HEAT FLOW at STONE & MASONRY FOUNDATIONS

• Buckled, Bulged, Leaning stone walls: Frost Push or Vehicle Loading
  
  foundation walls may be bulged or pushed inwards due to frost, water, or occasionally from vehicle loading if vehicles are driven close to foundation walls

• Cracked stone walls (if mortared)
• Stone wall settlement 

• Stone foundation wall interruption, removal of portions of the wall, & loss of structural integrity 
  
  such as where stones have been removed from a structural wall to add a door or to provide access for mechanicals.
  
  Unless appropriate measures are taken, such as adding a lintel or other support, removing stones from a structural stone wall may destroy the integrity of these walls. Click to enlarge the stone wall photo above for a sharper view of the cracking, bulging, collapsing stone wall resulting in part from removal of some of its components.
  
  In original construction stones were placed in an interlocking and overlapped pattern from course to course. Removing a section of wall may result in future wall movement unless other steps are taken to stabilize the modified section.

The Carson Dunlop Associates sketch below shows typical construction of a stone foundation atop which is placed a wood frame structure. We continue with our list of inspection points for stone foundations.

Below the stains down this stone foundation suggest a history of leaks focused around the basement window.

• Water leakage 
  
  is very common with all stone walls, especially dry-laid stones which were placed without use of mortar. (Photo below)
  
  In original use such walls were often expected to be leaky and provision was made for water passing through the wall to continue across a sloped (dirt) floor and out of the basement or crawl space.

• Building modernization effects
  
   on homes built on stone foundations:
  
  As such older buildings have been converted to modern use often owners add insulation, storm windows, siding, caulking, central heating, and a basement or crawl space floor slab.
  
  These improvements make for significant changes in how the building works and how water and moisture can (or cannot) escape, and can lead to severe water entry problems and related problems of insect damage, rot, and indoor mold in the building.

Types of Stone Used in Building Foundations

Photo above: stone walls, pyramids and steles at Calakmul, Yucatan, Mexico. (Friedman)

The stone used at Calakmul in Mexico was a soft limestone, mined nearby. Limestone is comparatively soft which explains why some of the monoliths in our photo are so worn as to have lost inscriptions and images.

Foundation Stone Choice: Driven by Proximity

In most parts of the world builders used whatever reasonably-hard stone was closest to the job site, since transportation cost is a significant factor.

But on occasion stones were moved from afar.

The bluestones used to construct the monolithics at Stonehenge (ca 1900 B.C.E.) are an igneous stone from the Preseli Hills over 225 kilometers (about 140 miles) away in western Wales.

The Stonehenge photos above and below are by Friedman and were taken in 1972.

Some of the authors whose work on the history of Stonehenge that we reviewed think that the stones were floated down the Avon river to get them to the Stonehenge site in the Salisbury Plain in Wiltshire, England.

So while it's true that sometimes special stones were transported great distances, usually stone structures used locally available stone for the obvious reason that stone is heavy and troublesome to transport. We make best use of what's close-by.

Building Foundation Stone Types / Names

Of the 3 broad classes of stone, igneous, metamorphic and sedimentary, the first two make best foundation material but some sedimentary stone too may be hard and stable enough to use.

Photo: the Balsatic Prisms of Santa Maria Regla, near Husaca de Ocampo, las prismas balsaticas in Hidalgo, Mexico, photographed by the author in April 2018.

These basaltic canyon walls are lined by tall vertical 5-sided or 6-sided polygons of basalt that range in height from just a few feet (at the canyon bottom) to 164 feet high above the water level.

Popular for centuries among Mexican peoples the canyon was promoted among Europeans and tourists from the north following a visit to the site by German geographer Alexander von Humboldt in 1803.

Below our second photo gives a closer look at the pentagonal and hexagonal layered basalt columns while the author [DF] provides a reference of scale.

Popular types of stone used for foundation use include

• Basalt -
  
  (our favorite) is a very dark / black fine-grained volcanic rock, sometimes formed in a columnar structure.

Photo above: a closer look at the geometric form of the Balsatic Prisms of Santa Maria Regla.

• Gneiss -
  
  a "high grade" metamorphic rock that is banded, layered, or "foiliated" in structure, coarse-grained, principally made up of feldspar, quartz, and mica.
• Granite -
  
  a very hard granular, crystalline igneous rock widely used in building construction
• Laterite
  
  stone is formed by the weathering of igneous rocks in moist warm climates, or a clay-soil high in aluminum oxide and iron.
  
• Limestone
  
  (depending on the quality and hardness) - limestone is a hard sedimentary rock, principally Dolomite or Calcium Carbonate.
  
  Also see our discussion of cleaning stains from limestone at
  
  STONE, STUCCO & BRICK CLEANING METHODS
• Marble
  
  another metamorpiic rock, is metamorphosed limestone or dolomite, both of which contain a high concentration of calcium carbonate (CaCO₃).
  
  Marble is rarely as a building foundation or wall stone except where construction is close to marble quarries
• Quartzite -
  
  a very hard granular rock, possibly silicified or metamorphosed sandstone (Sarsen stones).

Photo above: deteriorating brownstone on a building in Brooklyn, New York.

Below, a more-durable brownstone building behind the Alexander Pollock family and the author's previoius wife Harriet in Edinburgh, Scotland in 1972. (Mr. Pollock, a former Scottish Conservative Party politician was a young barrister when the author took this photo.)

• Sandstone & Brownstone
  
  a sedimentary rock formed by sand (quartz) grains cemented together, typically red, yellow or brown in color; Brownstone may also be used in foundations depending on quality, hardness, stability of the particular stone and its source quarry.
  
  Brownstone, a reddish brown stone (thanks to the presence of iron oxide (FeO₂) has been popular for building facades, lintels, steps, is a type of sandstone.
  
  See also STAINS on SANDSTONE, DIAGNOSE & CURE 
  
  See also MASONRY FACADE / WALL, LINTEL & BROWNSTONE DAMAGE
• Schist -
  
  a medium-grade metamorphic rock, harder than slate, softer than granite or gneiss.

• Slate
  
  "stone" is a fine-grained metamorphic rock with perfect cleavage. It's that cleavage that allows slate to be split into thin layers widely used as roofing, or in thicker forms as walks. Slate as a building wall or foundation material is not common, again depending on hardness and stability and resistance to fracturing.
  
  See also SLATE ROOF COLORS & SLATE CHEMISTRY
• Trap stone -
  
  any dark igneous rock crushed to random shapes
• Travertine stone -
  
  stone formed in hot springs and/or limestone caves, similar to marble, granite, onyx, limestone, slage (thanks to travertinewarehouse.com )

Popular foundation stones by stone shape or form

Photo above: this fieldstone foundation at a pre-1900 New York home was leaky and damaged enough that a previous building owner had begun constructing a concrete block inner "wall" to help stabilize the structure.

Notice that the fieldfstone, un-cut / un-finished, and that it is two or more feet in thickness.

• Fieldstone
  
  un-finished stone that is used in its natural form as found in nature, typically from arable or pasture land, in piles also called "clearance cairns".

Photo above: a quarry stone foundation in San Miguel de Allende, Mexico. These stones have been rough-finished on at least one side to give a flat surface.

• Quarry stone -
  
  stone removed from an open pit mine, excavated, usually finished on one or more sides.
  
  Some quarry stones of particular properties or from a specific location take their name from the quarry, such as bath stone.
  
  Bath stone is an oolitic limestone formed 195 to 135 million years ago during the Jurassic period and mined in Bath in Somerset England, the U.K. (Bath is so named for its Roman-constructed baths).

Photo above: a river stone house photoraphed by DF in Germfask, Michigan in 2023.

• River stone -
  
  stones of various types found in a riverbed, typically smoothed by the action of water and movement of other stones and abrasives carried by water.

Soft Forms of Stone to Avoid for Foundations

What people would avoid (but you may still find) would include softer stones or stones that fracture or cleave easily, such as SOFTER forms of

• sandstone
• brownstone
• slate

Popular Stone Foundation Materials by Form in Which Used

Stone may be used in construction of building foundations or walls in these shapes or forms:

• its natural form or shape
• rubble
• rounded
• worked into squared faces or into just one or two squared faces.

Frost Push & Heat Flow at Stone Foundation Walls

Here we explain the causes of frost push or frost damage to foundation walls.

Above in an illustration by Friedman we show how a combination of wet soil and freezing conditions conspire to create frost push against a foundation wall. The maximum point of inwards wall bulge occcurs where the frost pressure is greatest.

That's going to be above the frost line and at a depth that depends on the extent to which water, usually from roof spillage or from in-slope grade cause water to collect outside the foundation wall.

Our illustration below, adapted by Friedman from an original by Farouki (1992) illustrates the heat flow down into the surrounding soil from an insulated building in a freezing climate. This illustration explains how to AVOID frost damage to foundations.

Farouki notes

... insulation is used in association with foundations of structures as part of a process of thermal engineering to produce safe and economic designs for various structures.

The use of insulation enables heat management that allows shallower foundation depths and prevents damage from frost action.

Results are given from the Norwegian Frost I Jord research project and the work at Lund University, Sweden, both of which provided the basis for the design guidelines of Norway, Sweden and Finland. -References or Citations

If we reverse the size and direction of that big orange arrow we might portray frost push effects on the foundation wall - look again at our first drawing.

Frost Push Damaged Foundation Field Report

Below: as an example of foundation frost push damage, these foundation damage photos, contributed by ASHI home inspector David Grudzinski illustrate the importance of looking carefully at the building exterior for early clues that you may track down to more-significant damage.

This masonry block (above-grade) foundation was not straight-vertical but instead was out of plumb, as Grudzinski noted.

A very rough measurement showed that the block surface was six degrees out of plumb.

Even a casual and thus incomplete examination of David's photos provides an experienced inspector with more foundation damage and damage history clues.

Above in our first photo notice that sloppy spilled concrete at the juncture of concrete sidewalk and foundation wall? That may be an attempt to seal water leaking between the sidewalk and foundation, but

notice too that the sidewalk, though it slopes nicely away from the home, dumps water into a water trap (as from there soil slopes uphill) that will pretty much trap water along the building, inviting water seepage down into soils close to the foundation - adding to the risk of frost damage.

Notice below that rather new asphalt paving has been put around these foundation areas,sloped away from the home. Someone may have been attempting to stabilize the foundation and stop water and frost damage by adding this paving and drainage.

But notice too the frost damaged concrete blocks at the corner: probably frost heave.

And notice as well the crushed downspout end still spilling (if it could spill) close to the foundation? So we have a clue that the building owners/occupants are not aware of or don't notice critical roof drainage system maintenance tasks.

For the scientists among us,

see ROOF SLOPE CALCULATIONS

for formulas to convert angle or slope over a distance to inches out of plumb over a height. A foundation wall that is bulged an inch or more out of plumb at its most-bulged point over its height is considered significantly damaged and needing further evaluation and possible repair. (Friedman & Seaquist).

Details are at FOUNDATION DAMAGE SEVERITY

and at FOUNDATION or WALL BULGE or LEAN MEASUREMENTS

Inspecting the building interior Grudzinski found still more-significant damage to the stone foundation laid below-grade.

[Click to enlarge any image]

Here are Mr. Grudzinski's notes to us:

Attached in several emails will be photos of a stone foundation severely buckled in from expansion in soil caused by frost heaves. The home is an 1980 Colonial 2-family home in Pawtucket RI. The prospective buyer is a past client, and saw the home under limited lighting in the early evening hours.

The home was being "flipped" by a contractor. The first signs of concern were walking around the exterior.

The foundation is stacked Rubble stone to grade, with cement block above grade. There was an obvious deformity in the Block foundation condition. It was not plumb, and when sighting the foundation on the longer planes, the center was buckled in at least 6 inches when compared to the corners.

The gutter downspouts deposited the water right at the base of the home, rather than away from the home.

The rear wall was notably more deformed than the side walls. I used an angle gauge with a level to come up with a rough idea of the angle of the foundation from grade level to the Mud Sill. The block portion of the foundation was 8 Degrees out of plumb. This translated to 3 inches over 2 ft.

Upon entering the basement, the stacked stone showed an inward displacement of around 12 inches at the farthest point. The stone wall had large openings where smaller stones were missing and the mating surfaces of the stones had separated. The line where the Blocks were stacked on the stone showed openings.

Because of the movement, the rear wall of the 1st floor was angled outwards about 6 inches, and the siding was separated from its original location.
This foundation will need significant structural repairs to the foundation.

• David Grudzinski, Advantage Home Inspections, ASHI cert # 249089, HUD cert# H-145, is a professional home inspector who contributes on various topics including structural matters.
  David Grudzinski, Cranston RI serving both Rhode Island and Eastern Connecticut can be reached at 401-935-6547 fax- 401-490-0607 or by email to Davidgrudzinski@aol.com
  
  Mr. Grudzinski is a regular contributor to InspectAPedia.com

Related topics

• FOUNDATION DAMAGE by ICE LENSING 
• FOUNDATION FAILURE by INSULATION 
• FROST HEAVE / EXPANSIVE SOIL CRACKS in SLABS
• FROST HEAVES, FOUNDATION, SLAB
• HORIZONTAL MOVEMENT IN FOUNDATIONS

Research on Frost Heave & Frost Push Damage to Building Foundations

• Bonshor, Ronald B., Lesley L. Bonshor, and Roger Sadgrove. Cracking in buildings. Construction Research Communications Limited, 1996.
• Crory, Frederick E., and R. E. Reed. Measurement of frost heaving forces on piles. No. CRREL-TR-145. COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH, 1965.
• Everett, D. H. "The thermodynamics of frost damage to porous solids." Transactions of the Faraday society 57 (1961): 1541-1551.
• Farouki, Omar. EUROPEAN FOUNDATION DESIGNS FOR SEASONALLY FROZEN GROUND [PDF] No. CRREL-Mono-92-1. Cold Regions Research And Engineering Lab Hanover NH, 1992. Retrieved 2019/11/11 original source https://apps.dtic.mil/dtic/tr/fulltext/u2/a250833.pdf
  Abstract:
  
  The report deals with the design of foundations against frost action in Europe, particularly as practiced in the Nordic countries. It describes how insulation is used in association with foundations of structures as part of a process of thermal engineering to produce safe and economic designs for various structures.
  
  The use of insulation enables heat management that allows shallower foundation depths and prevents damage from frost action. Results are given from the Norwegian Frost I Jord research project and the work at Lund University, Sweden, both of which provided the basis for the design guidelines of Norway, Sweden and Finland.
  
  Detailed slab-on-grade designs ensure that frost heave does not occur.
  
  Consideration is given to the design of foundations with a crawl space or basement, with their problems of sidegrip and horizontal frost pressure. Frost protection for unheated buildings is described, usually involving the use of insulation and drainage layers below the foundation with ground insulation nearby to retain soil heat.
  
  Designs with open foundations are described as well as foundations for retaining walls and bridges. Frost protection required during winter construction is detailed. Building foundations, Foundation design, Frost heave, Europe, Frost action.
• Gullfiber (1986) Gullfiber insulation system. Gullfiber AB, Billerholm, Sweden (in Swedish)
• Haley, James F., Kenneth A. Linell, George A. Crabb Jr, Harry Carlson, and A. W. Johnson. "Soil temperature and ground freezing." HIGHWAY RESEARCH BOARD WASHINGTON DC, 1953.
• Hansen, N-E. Ottesen, and Helge Gravesen. "ENGINEERING PRACTICE FOR ICE FORCE DESIGN IN DENMARK." [PDF]
• Lin, Jun, and D. Scott. "Assessment of significances of building failure induced by foundation failure: facade failure, and moisture problem." In Building Integration Solutions, pp. 1-13. 2006.
• Lisø, Kim Robert, Tore Kvande, Hans Olav Hygen, Jan Vincent Thue, and Knut Harstveit. "A frost decay exposure index for porous, mineral building materials." Building and Environment 42, no. 10 (2007): 3547-3555.
• Penner, Edward, and Lorne W. Gold. "Transfer of heaving forces by adfreezing to columns and foundation walls in frost-susceptible soils." Canadian Geotechnical Journal 8, no. 4 (1971): 514-526.
  Abstract:
  
  The paper gives results of field studies on uplift forces on small-diameter columns of steel, concrete, and wood caused by adfreezing in frost-susceptible Leda clay. Adfreeze strength values would appear to be highest for steel and concrete, followed closely by wood. The heaving pattern and the heaving force transmitted are shown to be different for long foundation walls than for isolated columns. This compares favorably with the deformation pattern induced in an ice cover around offshore structures, during a change in water level.
  
  Attention is also given to the relative movement of the heaving soil with respect to the structure and the influence of the heave pattern on the transmission of forces.
• Penner, Edward. "Uplift forces on foundations in frost heaving soils." Canadian Geotechnical Journal 11, no. 3 (1974): 323-338.
  Abstract:
  
  Field studies of uplift forces by frost heaving are described for columns of various types and sizes and for a block concrete wall. The changing ground surface heave pattern around the block wall was used to predict the maximum heaving force which compared favorably with the measured value.
  
  Unit adfreeze strengths and maximum uplift forces were highest for steel columns, followed by concrete and wood; the lowest values were for the block concrete wall.
  
  In general, unit adfreeze strengths were highest for the small diameter columns and lowest on the largest columns. Differences are ascribed to the response of the various materials to air temperatures and to the shape and size of the structure.
• Penner, Edward. "Particle size as a basis for predicting frost action in soils." Soils and Foundations 8, no. 4 (1968): 21-29.
• Rockwool (1984) BYGG - A Book on Building Insulation. Rockwool AB, Skovde, Sweden (in Swedish)
• Saetersdal, Reidar. "Heaving conditions by freezing of soils." Engineering Geology 18, no. 1-4 (1981): 291-305.
• Stuart, Matthew, "Concrete Slab Finishes and the Use of the F-number System", Matthew Stuart, P.E., S.E., F.ASCE, online course at www.pdhonline.org/courses/s130/s130.htm
• Vialov, S. S., V. G. Gmoshinskii, S. E. Gorodetskii, V. G. Grigorieva, and Iu K. Zaretskii. The Strength and Creep of Frozen Soils and Calculations for Ice-Soil Retaining Structures (Prochnost'i Polzuchest'merzlykh Gruntov I Raschety Ledogruntovykh Ograzhdenii). No. SIPRE-TRANS-76. COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH, 1965.
  
  Abstract : Mechanism of Rheological Processes; Principles of Calculation for the Creep and Long-Term Strength of Frozen Soils; Cryogenous Texture and Strength of Frozen Soils;
  
  Methods for Testing Frozen Soils in Creep and for Long-Term Strength; Experimental Study of the Creep of Frozen Soils; Experimental Study of the Long-Term Strength of Frozen Soils; Calculations for Strength and Creep of Mine Shaft Retaining Structures Sunk by Means of the Freezing Process; Models of Ice-Soil Cylinders; and Comparison of the Analytical Solutions with Model Results, and Recommend Formulae for Calculations.
• VTT (1987) Frost protetion guidelines for house structures, Technical Research Center of Finland Geotechnical Laboratory, Helsinki, Finland (in Finnish)
• Also seeReferences or Citations at the end of this article