Excessive Moisture Could be Damaging Your Home and Threatening Yours and Your Families Health
Moisture issues in a structure provide conducive conditions for all types of pests and micro-organisms. Roaches, ants, and other household pests find a suitable breeding ground in moist conditions and wood-destroying insects often prefer to infest moist wood. Micro-organisms like fungi, mold, and bacteria generally grow, thrive, and spread under these conditions. They can pose a threat to the physical integrity of the structure and to the health of the occupants. For instance, if left unchecked, the growth of wood decay fungi will cause the wood to rot and be unable to support the weight. In addition to this, inhaling airborne bacteria as well as mold and fungus spores can cause serious health issues. So addressing the cause of the moisture issue and fixing it is critical to the health and safety of both the structure and its occupants.
There are only 6 causes for moisture issues in or under a structure. Each has a differing solution depending on the cause. The six causes are Ground Moisture, Water Infiltration, Water Leaks, Moisture Introduction, Rhizomorph Introduction, and Atmospheric Moisture. Of these six only four are common likely causes.
The four common causes of moisture issues in a crawlspace are:
- Ground Moisture – This is moisture coming up from the ground itself and into the air in the form of water vapor. The insulation as well as the wooden members absorb the moisture from the air causing them to get moist. If the moisture levels rise beyond a certain point it can cause the growth of bacteria, fungus, and mold. Remediation usually consists of the installation of a properly installed moisture barrier (aka vapor barrier).
- Water Leaks – Plumbing leaks, roof leaks, leaking hot water heaters, leaking HVAC drain lines, and so forth are all sources of water. Water, even when not making direct contact with insulation or wood, is almost always converted to water vapor and therefore moisture. Depending on the severity of the leak, the moisture problem can be small, moderate, or significant. Remediation is usually straightforward, simply repair the leak to stop the introduction of water and moisture.
- Water Intrusion – Water intrusion is water that enters into the crawlspace from a natural source. It can come up from the ground, in through the vents, in through the foundation, under doors or a combination of any of these. Remediation is usually a matter of redirecting the water someplace else. Installation of vent wells or fixing improperly installed vent wells will often address water entering through the vents. Regrading the ground or the installation of a drain and catch basin can address water entering under doors. Water coming up from the ground or in through the foundations wall(s) is usually addressed by the installation of a sump and pump system, or a French drain, or both.
- Atmospheric Moisture – Atmospheric moisture is just the moisture of the air native to the surroundings. High atmospheric moisture levels are often determined by the elimination of all other moisture sources. If all the other possible sources of moisture introduction have been eliminated or accounted for, and the moisture levels are still high or excessive, then atmospheric moisture must be the culprit. Remediation usually consists of sealing the crawlspace and installing a dehumidifier to control the atmospheric moisture.
The two uncommon causes are:
- Moisture Introduction – This is the introduction of moisture to an area by mechanical devices, often by intentional means. Humidifiers are an example of these devices. It is rare that such devices are the cause of excess moisture to the point of being a detriment. Simply discontinuing the use of such devices would be the recommended remediation for this situation.
- Rhizomorph Introduction – Moisture is introduced to wooden members by a water translocating fungus via a system of root-like structures called rhizomorphs. These fungi can transport moisture from areas of high concentration to areas of low concentration. Remediation consists of killing the fungus in all parts of the structure. This can be a lengthy complex process depending on the severity of the infestation. Luckily, attacks by these types of fungi are rare.
We offer a full line of moisture control products
This is the product we find most often improperly installed. The correct method for installing a moisture barrier starts with removal of the old barrier. The new barrier should never be laid on top of the old barrier as it allows moisture to become trapped between the two barriers. This permits mold, bacteria, and fungus to grow leading to foul odors or even allowing harmful microorganisms to get airborne and enter the living space.
The ground should be prepared prior to the installation of the moisture barrier to provide maximum longevity to the moisture barrier. By prepared we mean that large rocks, construction debris, and any other objects that could puncture or tear the moisture barrier be removed and taken away. The individual sheets of the moisture barrier should be joined together to create a single continuous barrier. The entire barrier should be affixed to the ground so it cannot move or shift out of position. Drains or French drains should be left purposefully uncovered so that water can access them unhindered.
Whether you want to replace broken foundation vents, upgrade your vents to automatic foundation vents so they open and close automatically, make openings and install additional vents for increased ventilation, or install vent fans in increase circulation, we have the products and knowhow to get the job done correctly.
If water is entering into the structure through the window(s), crawlspace door(s), or foundation vent(s) or if they are rotting due to pooling water installing window wells, crawlspace door wells, or vent wells may be the solution. A proper installation starts with digging a reservoir 96 cubic inches per inch of length of well. Then adding drainage rock until the rim of the well sits approximately 3 inches above grade when placed in the reservoir hole. The drainage rock at the back of the well is covered with a sediment barrier and filled with soil and the sod (if applicable) is replaced. The interior of the well is filled with drainage rock up to 1 inch below the bottom of the vent or window or crawl door. This allows water to drain rapidly into the reservoir and eventually leech in the ground.
Improperly installed vent wells can actually cause the very problem they are designed to fix. Soil drains slowly, so vent wells with soil at the bottom act like a cup during heavy rainfall filling up and pouring in the vent, window, or crawlspace door. We can also rehab any mis-installed vents to get them functioning like they should.
Drain and catch basin systems are often used in low spots in a slab, at the bottom of the basement stair well, or anyplace where water pools and a French drain would be impractical. Water in the underground catch basin can be allowed to drain out normally or can be pumped out if circumstances make it a necessity. These systems come in all shapes and sizes, can be installed in a variety of locations, and under a variety of circumstances. So exact installation procedures can differ from one install to another. However, in general this consists of burring a basin underground, often permeable to allow the water to leech out, and installing a drain with some type of porous cover at the top. We can handle the installation of all sized systems from a small patio drains to large commercial drains, call us for your free estimate.
Whether you want to replace broken foundation vents, upgrade your vents to automatic foundation vents so they open and close automatically, make openings and install additional vents for increased ventilation, or install vent fans in increase circulation, we have the products and knowhow to get the job done correctly.
French drains are used to remove pooling water by transporting the water to a more suitable area or to a sump where it will be pumped out. French drains can be along the exterior, in a crawlspace, in a basement, along a driveway, patio or other type of slab. They can be covered in drainage rock or grating. The drain needs to be installed at a negative to neutral slope towards the drainage point to insure a positive flow of water. Installation of a debris filter is critical to prevent sediment buildup inside the pipe which may impede or block the flow of water. If the water flow is blocked or severely impeded it can cause the French drain to fail completely causing a resurgence of the problem the drain was installed to fix. Lastly drainage rock or grating should be used to allow the water access to the drain. The drainage rock should be #57 rock. Smaller rock can trap debris and be more difficult to clean.
Perforated pipe should be used for where water is collected & transported, in areas where the water is transported but not collected it is best to use solid pipe to prevent root infiltration. Transitioning to PCV is better option than using solid 4″ corrugated pipe as it is more resistant to accidental damage. Lastly the terminal end of the pipe should have an exclusion device installed that will prevent critters from entering the pipe, getting stuck, and creating a blockage, and at the same time allow water to flow freely. We have the expertise to design and install French drains correctly or fix an existing one that has failed due to age or improper installation.
Installation of dehumidifier systems, especially in crawlspaces, seem to be the most improperly installed moisture control device we come across. The dehumidifier needs to match the application it is being used for or it may, at the very least, not perform properly. A dehumidifier installed in conditions it wasn’t designed for can cause it to continually break down requiring repeated repair or replacement, or at worst cause a fire (Crawlspace conditions tend to be brutal conditions for electronic equipment). Even if the dehumidifier fits the application, often the surroundings need to be modified so it can work efficiently without undue stress that can cause premature failure of the unit. In crawlspace, this typically requires sealing the crawlspace.
Dehumidifiers used for crawlspace applications almost always have built-in humidistats so they only run when the humidity rises above a set point. So, the first step is to install a 100% moisture barrier with a minimum thickness of 6mm to lockout the continuous supply of moisture from the ground that would cause the dehumidifier to run more often than necessary. Installation of a moisture barrier will also prevent the ground from becoming abnormally hard and fissured as the moisture is sucked from it.
The gaps in the foundation need to be sealed as much as possible, vents blocked off, and crawlspace doors installed if missing or damaged in order to prevent a constant supply of moisture from being reintroduced from the outside causing the dehumidifiers to run continuously (this would be similar to running the AC indoors with the windows and doors wide open).
Porches can be a source of moisture and may need segregated from the rest of the crawlspace, especially if they have slats that are open to the outside. This can be as simple as the installation of a foundation door or as complex as having to construct a curtain or foundation wall. The physical installation of the dehumidifier requires access to electricity and the installation of a drain line to allow the collected water to be removed from the crawlspace. If the drain line cannot be negatively sloped the installation of a pump is usually necessary.
