What is the dry standard and how do you calculate it?
By Fred McGuire/Jerold Anderson
When faced with water damage, drying building materials back to its original state is your goal. So what are the dry standards and how do I know when I get there?
Let’s start by defining the Dry Standard: The drying goal established in water restoration. It is determined by measuring the moisture content of unaffected materials in an environment.
Simply stated: A sample reading taken on an unaffected material. This reading is then used as the unaffected control or drying goal.
We see the effects of water damage on walls every day. Drywall is a panel made of gypsum plaster pressed between two thick sheets of paper. Its thickness varies between one-half inch and five-eighths inches. Meanwhile, lathe and plaster is a building process used to finish mainly interior walls and ceilings in the United States until the late 1950s. After the 1950s, drywall began to replace it.
Drywall and plaster can absorb water and be successfully dried. For drywall, if the paper is wet but the gypsum inside has not started to degrade; you are probably ok to salvage it. If the paper is saturated and the gypsum is starting to turn mushy, or is crumbling you are likely too late.
When drywall is wet, it can be dried without demolition if a trained professional does the work. This requires a combination of the proper number of air movers and dehumidifiers. Drywall will dry to a hardness that will be equal to other areas that were not wet and much less costly to do so. Therefore we often dry walls without removing them.
So how do you know when a wall is dry? Using a non-penetrating moisture meter, you begin by determining the dry standard for that home by testing it in an unaffected area. This should be at least 5 feet away from any wet area or in an unaffected room of the house. That is the dry-standard for the home. In Minnesota it is normally reads from 7 to 9.
Plaster/lathe normally takes longer to dry than sheetrock. It may take the infusion of extra heat over the surface to increase the energy so water molecules move faster speeding evaporation. Expect dry times to be 5-7 days vs 3-5 for sheetrock. Drywall nailed over paneling, and the reverse, is a challenge. These layers don’t promote drying. We can’t dry it easily.
According to the IICRC the drying process can be finished when the readings are within 4 points of the original dry standard. Then you can expect materials to finish drying the rest of the way in a few more days.
Wood floors have a normal dry standard of their own. Check a dry place on the floor for set your standard and then check daily to monitor the results. Solid wood floors often respond well to the drying process, laminate floors not so much. Laminate flooring most often is replaced due to its composite construction which warps when wet. Hardwood floors warp also but they can be dried and regain their original shape. Laminate floors most often need to be replaced.
Carpets are dried after the pad is removed and discarded. They respond well to air movers and dehumidifiers. Oftentimes the carpet is floated by and air mover as part of the drying process. Later the pad is replaced and the carpet re-stretched. However if carpet is wet for too many days, it will delaminate as the glue breaks down and needs to be replaced.
Rely on ServiceMaster to attempt to dry all structures and building materials rather than replace them which saves time and money. Our highly trained staff will do their best to do so and therefore will save money on each claim.