- Given the right conditions, water can seep into your house through the foundation walls. These leaks are seldom caused by faulty plumbing. Foundation walls crack and leak when water soaks into the walls and eventually begins to drain inside of your basement. Leaks in foundation walls are usually fixed in 1 of 2 ways.
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- General considerations
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- Physical properties
- Mechanical properties
- Thermal properties
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Rock, in geology, naturally occurring and coherentaggregate of one or more minerals. Such aggregatesconstitute the basic unit of which the solid Earth is composed and typically form recognizable and mappable volumes. Rocks are commonly divided into three major classes according to the processes that resulted in their formation. These classes are (1) igneous rocks, which have solidified from molten material called magma; (2) sedimentary rocks, those consisting of fragments derived from preexisting rocks or of materials precipitated from solutions; and (3) metamorphic rocks, which have been derived from either igneous or sedimentary rocks under conditions that caused changes in mineralogical composition, texture, and internal structure. These three classes, in turn, are subdivided into numerous groups and types on the basis of various factors, the most important of which are chemical, mineralogical, and textural attributes.
General considerations
Rock types
Igneous rocks are those that solidify from magma, a molten mixture of rock-forming minerals and usually volatiles such as gases and steam. Since their constituent minerals are crystallized from molten material, igneous rocks are formed at high temperatures. They originate from processes deep within the Earth—typically at depths of about 50 to 200 kilometres (30 to 120 miles)—in the mid- to lower-crust or in the upper mantle. Igneous rocks are subdivided into two categories: intrusive (emplaced in the crust), and extrusive (extruded onto the surface of the land or ocean bottom), in which case the cooling molten material is called lava.
Sedimentary rocks are those that are deposited and lithified (compacted and cemented together) at the Earth’s surface, with the assistance of running water, wind, ice, or living organisms. Most are deposited from the land surface to the bottoms of lakes, rivers, and oceans. Sedimentary rocks are generally stratified—i.e., they have layering. Layers may be distinguished by differences in colour, particle size, type of cement, or internal arrangement.
Metamorphic rocks are those formed by changes in preexisting rocks under the influence of high temperature, pressure, and chemically active solutions. The changes can be chemical (compositional) and physical (textural) in character. Metamorphic rocks are often formed by processes deep within the Earth that produce new minerals, textures, and crystal structures. The recrystallization that takes place does so essentially in the solid state, rather than by complete remelting, and can be aided by ductile deformation and the presence of interstitial fluids such as water. Metamorphism often produces apparent layering, or banding, because of the segregation of minerals into separate bands. Metamorphic processes can also occur at the Earth’s surface due to meteorite impact events and pyrometamorphism taking place near burning coal seams ignited by lightning strikes.
Rock cycle
Geologic materials—mineral crystals and their host rock types—are cycled through various forms. The process depends on temperature, pressure, time, and changes in environmental conditions in the Earth’s crust and at its surface. The rock cycle illustrated in Figure 1 reflects the basic relationships among igneous, metamorphic, and sedimentary rocks. Erosion includes weathering (the physical and chemical breakdown of minerals) and transportation to a site of deposition. Diagenesis is, as previously explained, the process of forming sedimentary rock by compaction and natural cementation of grains, or crystallization from water or solutions, or recrystallization. The conversion of sediment to rock is termed lithification.
Abundance of rock types
An estimate of the distribution of rock types in large structural units of the terrestrial crust is given in the Table. The relative abundance of main rock types and minerals in the crust is shown in the Table.
Texture
The texture of a rock is the size, shape, and arrangement of the grains (for sedimentary rocks) or crystals (for igneous and metamorphic rocks). Also of importance are the rock’s extent of homogeneity (i.e., uniformity of composition throughout) and the degree of isotropy. The latter is the extent to which the bulk structure and composition are the same in all directions in the rock.
Analysis of texture can yield information about the rock’s source material, conditions and environment of deposition (for sedimentary rock) or crystallization and recrystallization (for igneous and metamorphic rock, respectively), and subsequent geologic history and change.
Classification by grain or crystal size
The common textural terms used for rock types with respect to the size of the grains or crystals, are given in the Table. The particle-size categories are derived from the Udden-Wentworth scale developed for sediment. For igneous and metamorphic rocks, the terms are generally used as modifiers—e.g., medium-grained granite. Aphanitic is a descriptive term for small crystals, and phaneritic for larger ones. Very coarse crystals (those larger than 3 centimetres, or 1.2 inches) are termed pegmatitic.
For sedimentary rocks, the broad categories of sediment size are coarse (greater than 2 millimetres, or 0.08 inch), medium (between 2 and 1/16 millimetres), and fine (under 1/16 millimetre). The latter includes silt and clay, which both have a size indistinguishable by the human eye and are also termed dust. Most shales (the lithified version of clay) contain some silt. Pyroclastic rocks are those formed from clastic (from the Greek word for broken) material ejected from volcanoes. Blocks are fragments broken from solid rock, while bombs are molten when ejected.
Porosity
The term rock refers to the bulk volume of the material, including the grains or crystals as well as the contained void space. The volumetric portion of bulk rock that is not occupied by grains, crystals, or natural cementing material is termed porosity. That is to say, porosity is the ratio of void volume to the bulk volume (grains plus void space). This void space consists of pore space between grains or crystals, in addition to crack space. In sedimentary rocks, the amount of pore space depends on the degree of compaction of the sediment (with compaction generally increasing with depth of burial), on the packing arrangement and shape of grains, on the amount of cementation, and on the degree of sorting. Typical cements are siliceous, calcareous or carbonate, or iron-bearing minerals.
Sorting is the tendency of sedimentary rocks to have grains that are similarly sized—i.e., to have a narrow range of sizes (see Figure 2). Poorly sorted sediment displays a wide range of grain sizes and hence has decreased porosity. Well-sorted indicates a grain size distribution that is fairly uniform. Depending on the type of close-packing of the grains, porosity can be substantial. It should be noted that in engineering usage—e.g., geotechnical or civil engineering—the terminology is phrased oppositely and is referred to as grading. A well-graded sediment is a (geologically) poorly sorted one, and a poorly graded sediment is a well-sorted one.
Total porosity encompasses all the void space, including those pores that are interconnected to the surface of the sample as well as those that are sealed off by natural cement or other obstructions. Thus the total porosity (ϕT) is
where VolG is the volume of grains (and cement, if any) and VolB is the total bulk volume. Alternatively, one can calculate ϕT from the measured densities of the bulk rock and of the (mono)mineralic constituent. Thus,
where ρB is the density of the bulk rock and ρG is the density of the grains (i.e., the mineral, if the composition is monomineralogic and homogeneous). For example, if a sandstone has a ρB of 2.38 grams per cubic centimetre (g/cm3) and is composed of quartz (SiO2) grains having ρG of 2.65 g/cm3, the total porosity is
Apparent (effective, or net) porosity is the proportion of void space that excludes the sealed-off pores. It thus measures the pore volume that is effectively interconnected and accessible to the surface of the sample, which is important when considering the storage and movement of subsurface fluids such as petroleum, groundwater, or contaminated fluids.
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Wall Cracks and Other Ways That Water Enters Your Basement Stamford, CT
Water is an enemy of your basement. Water, moisture, humidity, condensation, all can lead to mold. If you think that you’re safe from mold because you don’t have puddles of water in your basement when it rains, you are feeling a false sense of security. Lack of sun and fresh air, stagnant air, wall cracks, and more lead to your basement being a prime space for mold growth. Water gets into your home in a variety of ways, and there are some things that you should be checking to ensure your basement stays dry.
In Other Waters Cracks
Ways That Water Enters Your Basement
- Wall cracks are a common way for water to come in.
- Cracked footer tiles.
- Water can get pushed up through the floor.
- Moisture and condensation due to the weather outside and humidity inside.
Signs That Water Is Getting Into The Basement
- Dampness in areas of your basement walls.
- Discoloration on painted areas.
- Wood rot on paneling or columns.
- Rusty areas on your water heater and other appliances.
- A musty smell. You may associate the smell of must and mildew as typical basement smells, but they are not.
What Can You Do To Make Sure Basement Waterproofing Is Completed Correctly?
The best thing to do when you have a wet basement is to call a professional foundation and waterproofing company to come out to inspect the area. They will determine if the water is indeed a problem, how it’s getting in, and how to fix it. These companies have a vast knowledge of water and the harm that it can do to your basement. Some of the fixes that usually get recommended include the following:
- Waterproofing your basement is one of the first fixes that you’ll need.
- Cracks will be filled and fixed.
- They will determine whether or not structural damage has taken place.
- Mold remediation is useful for basements that have mold.
Two things that you don’t want to do are to ignore water in the basement and to try to fix the problems yourself. Most products on the market that homeowners can buy, only offer temporary fixes. It’s also hard for the average homeowner to determine how to waterproof and fix the structural damage that may be taking place. Filling wall cracks won’t do much good if you have not solved the problem of pressure on the foundation, or poor soil. Let the professionals ensure that waterproofing gets done correctly, so you never have to worry about it again.
Contact the Professionals at Budget Dry Waterproofing Today! 203-421-8560
In Other Waters Cracked
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