Every water damage project eventually comes down to one simple question: is it dry?
That question sounds easy until you are the technician standing in a finished basement with a moisture meter in your hand, an adjuster asking for justification, a homeowner asking when the equipment can be removed, and a project manager trying to decide whether the structure is ready for rebuild. In those moments, “it feels dry” is not good enough. “The meter is lower than yesterday” is not good enough. “We have had equipment on site for three days” is not good enough.
Professional water damage restoration involves setting a target. And, most importantly, documenting the decisions and findings regarding that target. While there are some general principles involved, each project requires a tailored approach to dry standards and drying goals. In fact, ANSI/IICRC S500: 2021 Standard for Professional Water Damage Restoration discusses this topic in section 10.6.6, Dry Standards and Drying Goals. This section is one of the most practical parts of the standard for technicians and project managers because it deals with such practical aspects of restoration as equipment duration, demolition decisions, rebuild readiness and documentation.
The dry standard represents the reasonable approximation of moisture level or moisture content in a particular building material prior to water intrusion. In plain terms, it is the restorer’s best professional estimate of what “normal” looked like before the loss. The most effective approach would be evaluating similar building materials in unaffected areas of the structure. In other words, if hardwood flooring in a dining room was affected by the water, a similar sample in an unaffected living room would be analyzed as a dry standard. Similarly, if drywall in a recreation room was wet, the dry standard could be established after evaluation of similar material in other rooms.
This is important because buildings are not all the same. I recently purchased a home in Tampa, Florida, and it has reminded me how different building environments can be from one region to another Coming from Toronto where seasonal drying conditions can shift dramatically between – the cold winter, humid summer and warm indoor environment. In contrast, conditions in Tampa include a combination of high humidity, hot temperature, risk of storms, slab-on-grade construction, presence of air conditioning and, as you probably have already guessed, coastal climate. And all these factors affect moisture levels in a variety of building materials. That is exactly why it is necessary to establish a proper dry standard according to the S500 recommendations. Restorers in Florida would not apply numbers obtained in Canada. Dry standard should be related to a structure, the particular material and specific climatic conditions on the site.
Different building materials react differently to moisture. Wood, gypsum, plaster, concrete, engineered floors, trim materials, subfloors and cabinetry will not all absorb, store and release moisture equally.
That is why the S500 does not dictate restorers to use a universal dry standard in all cases. As stated in the standard, dry standard is expected to be reasonable and appropriate to the material. When there are no unaffected materials in the building, references can be made to other similar constructions. Personal experience and knowledge of a particular geographical area will help professionals make a wise decision. This is where training and field experience matter.
The drying goal may be at, or above, the dry standard. That point matters. In the real world, not every material has to be returned to an exact pre-loss moisture reading in order to be acceptable.The drying goal is different from the dry standard. Dry standard is an estimated moisture level in a particular material prior to the loss. Drying goal, in turn, is a particular number or range established by the professional during the restoration project. This is a target that should be reached prior to equipment removal or prior to making a certain next step.It may be higher or equal to the dry standard. But it should be reasonable and realistic. The drying goal is expected to return a particular structure or building component to an acceptable condition and prevent microbial growth.
Documentation is vital here. The record should include dry standard, the material and assembly evaluated, location of measurements, type of the meter used and the basis of the conclusions. Just writing the word “dry” into the file will be insufficient. A picture showing moisture meter readings without indicating material location, the name of the material and the goal will not prove anything. The records should be comprehensive enough to allow another professional to understand what has been done and what results were obtained.
There are also several limitations of moisture meters that professionals should know about. According to the S500, individuals responsible for establishing drying goals should be qualified through experience and training in the use and limitations of moisture meters. Why is it mentioned in this standard? Because the equipment is not a magic wand and its limitations should be taken into account. For instance, pin meters, penetrating meters, non-invasive meters, thermo-hygrometers and infrared cameras are different tools having their unique features and applications. Surface coating, salts, metals, density variations, insulation, voids, temperature and the composition of building materials may affect moisture readings.
A non-invasive meter may detect elevated area, but it cannot show which layer is wet. A pin meter provides more specific readings, however, they can only be provided at the depths and locations where pin probes are placed. Concrete readings are useful as comparisons, however, they should always be interpreted correctly. Readings of moisture content in wood should be adjusted considering the wood species, temperature correction, equilibrium moisture content and environmental conditions.
Project managers need to ask more than “What does the meter say?” They should ask questions concerning the nature of a building material, dry standard, drying goal, current trend, assembly type, the materials behind and beneath and the potential risks.
Based upon the S500 recommendations, the restorers will need to take into consideration many elements before setting up their objectives to achieve proper dry standards. This includes scope agreed upon, type of work, dry standard itself, project complexities and restrictions, construction characteristics, post drying state, seasonal conditions, regional history, installation requirements, and available documentation.
Also relevant are the seasonal conditions. A house in humid environment in summer would likely have different normal moisture levels than the same house during other seasons. Factors such as regional climate in Florida, exterior humidity, presence of HVAC and AC, building tightness, and exposure to storms all play role in determining what is reasonable in that particular building.
In any case, the purpose is not to complicate the process even further. The idea here is to improve quality of decision making and stop guessing when possible.
A frequent problem with water damage restoration projects is thinking of drying time as a number rather than part of the process. Duration of equipment used should correlate with the moisture levels and psychrometric conditions. As long as the process works, documentation should reflect it accordingly. In cases when no progress is observed, it is time to re-assess the process and possibly make adjustments such as changing equipment placement, increasing temperature, increasing dehumidification rate, uncovering hidden moisture, removal of unrepairable elements, etc.
Another frequent problem is the removal of equipment too early because surface moisture was not detected. Presence of hidden moisture may cause problems in the future, while keeping the equipment in place after achievement of desired moisture levels will cause wasteful expense and frustration. Both approaches are incorrect. Standards-based documentation can protect everyone involved – the contractor, the insurance company, the customer, and the entire project.
Drying goals also connect directly to microbial growth prevention. The S500 notes that drying goals should be expected to inhibit microbial growth, and additional information can be found in the ANSI/IICRC S520 Standard for Professional Mold Remediation. This is an important bridge between water damage restoration and mold risk management. The restorer’s job is not simply to lower numbers. The job is to return the structure, systems, or contents to an acceptable condition while reducing the conditions that support microbial amplification.
When it comes to restoration, technician’s task is not to get down to some low numbers, but restore the condition and reduce favorable conditions for growth of microorganisms as much as possible.
Of course, in certain situations consulting experts is recommended. This applies to complex flooring systems, historic materials, specialty wood products, plaster, concrete, large commercial facilities, disputes about acceptable moisture levels, etc.
Consulting an expert is not a weakness. It is often a sign of professional judgment.
What this means for technicians is clear – do not chase the random readings. Determine the dry standard. Set the drying goals. Learn about the material. Measure regularly. Record data. Report.
For project manager, it means requiring documentation to provide an accurate overview of the process. This will require information about affected areas, unaffected areas for comparison purposes, drying goals for particular material, daily measurements, psychrometric conditions, changes to the drying equipment, limitations, and final verification of results. If the documentation does not support the conclusion, the conclusion may not survive review.
The best restorers do not rely on habit, hope, or equipment days Instead, they follow standards, receive appropriate training, acquire practical experience, and keep detailed and accurate documentation. Particulars can be found in section 10.6.6 of the ANSI/IICRC S500 – a very helpful guide for answering that inevitable question on every project: “Is it dry?”
The professional answer should never be a guess. It should be a documented conclusion based on the material, the dry standard, the drying goal, the site conditions, and the restorer’s qualified judgment. That is how technicians protect the structure. That is how project managers control the file. That is how our industry continues to move from simply placing equipment to truly managing restorative drying.
Lorne McIntyre is a recognized expert in the cleaning and restoration industry, known for solving complex problems and raising the bar across the field. As Principal Technical Advisor at Verify Appraisal & Consulting, he’s a trusted resource for clarity, credibility, and results.
