Quote of the Day

Thursday, April 9, 2009

The Science of Drying a Structure

 

Mary was so embarrassed. She was sure that everything was dry from her "little flood," but looking at the red markers on the wall, she realized she was very wrong. The contractor had used some kind of meter and showed her where the walls were still wet. But how could the drywall be wet a foot up when the wall didn't feel wet or cold? And how would they be able to remove the water without tearing the wall apart?

For decades, the restoration industry used historical evidence in drying a structure. Basically, if it worked once, we would use it again. Everyone knew that moving air dried clothes and when the air was heated, it dried them even faster. No one really knew exactly why, but that didn't matter as long as it worked. So contractors put fans in houses for three days and said,"It is dry."

Today, using sensitive measuring devices, the industry has applied the laws of physics and chemistry to drying. Now, we not only know how the drying process works, we can predict with a great degree of accuracy, how long it will take and which technique will work best for a given situation.

There are three basic principles needed to dry a structure. Leave one out and the drying is delayed; leave two out, and drying grinds to a halt.

The first principle is heat - The more heat there is, the more energy is transferred to the water molecules and the more primed they are to move from one area to another. In most situations, the optimum temperature for drying a structure is between 90-105 degrees Fahrenheit. If it is much hotter, damage to the home can result. If it is too much cooler, the molecules will not be excited enough to move. Often, supplemental heat will need to be added to raise the temperature to the desired level.

The second principle is pressure - We control the direction of the water movement with air or atmospheric pressure and vapor pressure. The Bernoulli principle of physics explains that the faster a fluid is moving, the lower the pressures are inside the fluid. Air is a fluid, therefore, the faster it moves, the lower the pressure in the air. When the pressure of the ambient air in the room is less than the vapor pressure of the wet carpet, pad or drywall, the water molecules move from higher pressure to lower pressure or from the wet materials into the air. This migration is known as evaporation. The greater the pressure differential, the faster evaporation will occur.

The third principle is evacuation - Once the first two principles are successfully implemented, the air will quickly become saturated with water and evaporation will cease. Water molecules need to be evacuated from the room before evaporation can continue. In many situations, opening windows and doors to the outside will allow for the water to move out of the structure, lowering the vapor pressure in the room so evaporation can resume. This is especially effective on warm summer days. But when the temperature drops 30 degrees at night, high levels of humidity exist out of doors or security issues are present, other means of evacuation need to be employed. The most common option is a refrigerant dehumidifier.

The refrigerant dehumidifier cools the moist air to the dew point, forcing the water molecules to condense and fall out of the air. This water is collected in a holding tank and purged into a sink or floor drain when the tank is full. As the water is removed from the air, the pressure in the air is reduced allowing for more water to move from the wet materials into the air. Most refrigerant dehumidifiers work best in the 90-105 degree range.

There are several variations on these principles that can increase success in drying. Sometimes, hot, dry air is blown in to the building to create high pressure inside the room. This forces the air to leave through cracks and openings in the exterior, taking moisture with it. Other times hot, dry air will be pumped in to pressurize the walls while blowing fans lower the pressure of the room.

The best protocol to use will be determined by considering the following:

  • Amount of water present
  • Security concerns
  • Weather
  • Season of the year
  • Indoor and outdoor temperatures
  • Nature of the wet materials
  • Construction of the building

Using proper tools, including; moisture meters, thermal hygrometers and thermal imaging cameras, restoration contractors can dry most structures where the extent of damage does not require replacement.

Wednesday, March 25, 2009

What Do You Do After a Fire

         

1. Contact your insurance company. You need to report the fire, and your insurance company will give you valuable information regarding your coverage, including where to stay if your home is un-inhabitable. Your insurance company will usually dispatch an adjuster to evaluate the damage. Sometimes it will be that day, but often it is the next business day after the claim was reported.

2. Contact a reputable restoration company. You will need to choose a restoration contractor (such as Utah Flood and Fire) you are comfortable with. Your insurance company may recommend contractors in your area, but the final decision is yours alone. Your insurance company will pay the reasonable repair costs for most reputable companies. A restoration company will be able to help with the following items.

3. Secure the premises. Often in a fire, the firemen need to break doors or windows to enter the house or evacuate the smoke as quickly as possible. The fire may also have burned holes in the walls or roof. These need to be boarded up and/or covered as protection from weather and theft.

4. Restore the power. The power is usually shut off to the house as a precaution. The flames may have burned and exposed live wires that could short and start another fire. A qualified electrician is needed to separate the damaged circuits and restore power to the house. The power company often needs to inspect the building before they will allow the power to be restored.

5. Turn on the water. In major fires, the water is also shut off by the fire department. This is to prevent additional water damage from pipes that may have been damaged. This will need to be checked and turned back on before the cleaning process can proceed.

6. Restore the gas. The gas is also shut off as a safety precaution. A plumber is needed to check the gas connection and work with the gas company to restore the service.



Beautiful tri-fold copies of this article are available for distribution by insurance agents, adjusters, fire and police departments. Contact Utah Flood and Fire Network for more information




Friday, February 13, 2009

How To Spot A Bad Contractor

"What do you mean, 'It went a little over?'" Helen screeched. "The cost is twice as much as you promised, the cabinets look terrible and it's still not done! We went to the Olive Garden for Thanksgiving dinner, Cafe Rio for Christmas dinner but I will not go anywhere for Valentines Day. I want to cook dinner for my family in my new kitchen!"

Her contractor mumbled something about suppliers and subs, but she cut him off. "I am sick and tired of your excuses. I am sick and tired of your lies. I want this done by Friday or I will sue you for incompetence, . . . for ignorance and . . . and . . . . " In frustration Helen wheeled around and stormed out of the room as the tears began to flow.

What can you do to spot a bad contractor? They seem wonderful at the onset, they say all the things you want to hear, but before the job is over, you're ready to tear them apart, limb from limb.

Avoiding a shoddy contractor isn't as hard as most people imagine. There are tell-tale signs that can tip you off before you end up neck deep in a torrent of trouble. By carefully reading the descriptions below, you will be able to avoid the devastation of choosing the wrong contractor.
  1. Bad contractors are always late. I don't mean five or ten minutes late, either. Traffic or phone calls with other clients, can throw the best laid plans awry. With a bad contractor, late is measured in hours, days or weeks. Our company policy is to inform the client if you will be more than ten minutes late and reschedule if necessary.
  2. Bad contractors never return phone calls. You know to walk away when their voice message says, "We're sorry, but the mail box belonging to that number is full. Please try your call again later." Calls are not returned because there is no good answer for you and the decision is made to wait until there is. Since the answer never comes, the return phone call doesn't either. If a contractor doesn't have the courage to face up to life as it really is, they will not be able to control it and complete your job in a timely manner
  3. Problems are always someone else's fault. The builder sounds like an immature adolescent, unable to actually admit they made a mistake or attempt to correct it. Good contractors seldom have to explain what went wrong. All their time is spent explaining how it will happen and then they make it happen. They know that "the size of the mess you make is not nearly as important as how well you clean it up."
  4. Bad contractors always take two to three times longer than they promised. They have a bad habit of saying what you want to hear instead of what will realistically happen. This is usually an attempt to obtain the job. Good contractors will always estimate more time than actually needed. They realize things will go wrong, and if they don't, the project is completed sooner than you expected. Watch the consistency between what they promise and what they do from the very beginning. The primary rule to remember is: "When it's finished is not nearly as important as that it is finished when promised."
  5. Bad contractors never actually complete a project. There is always something that wasn't done or the perennial punch list that remains as a constant source of irritation. Good contractors will use sub-contractors who examine their own work, usually with the owner, and ensure everything is done properly before they leave. This habit virtually eliminates punch lists on smaller jobs and greatly reduces them on large ones. A task that will take one half-hour to correct while the technician is still there, with tools ready, will consume three to four hours if someone has to come back and do it later. Profitability and reputation go down the tubes.
You can also ask for referrals, credentials or lists of previous customers. Undesirable contractors are usually slow to provide these. Another problem is that if you do receive any referrals, they are often sanitized or fabricated. If you can talk to other customers, ask how the contractor was to work with and pointedly ask about the signs above.

If you watch for these tell-tale symptoms, you will be able to spot a bad contractor before you are in too deep and your repair or remodel can be a pleasant experience.



Tuesday, January 13, 2009

Understanding and Preventing Ice Damming


"Ice damming, what in the world was that?" Peter heard what the contractor was telling him, but the words didn't make any sense. There was water damage to the drywall and carpet in his living room and this sounded like a contrived excuse for someone to charge him a lot of money.

One of the least known and mis-understood forms of water damage comes from ice damming. It occurs when climatic conditions are just right. Heavy snow accumulation, combined with warmer days (35-40 degrees F) and freezing nights (20-30 degrees F) precipitate the formation of ice dams.

During the day, heat rising through the insulation from the interior of the house and warmer temperatures outside, begin to melt the snow. Water runs down the roof, under the snow, to the edge of the eve. Because there is no heat under the eve, the water freezes in the last foot or two, creating an ice dam. Day after day, it continues to increase the height of the dam. More and more water fills the reservoir. It begins to seep under the shingles because of capillary action. Water can wick up hill to a height of two to three vertical feet. Eventually, it finds a breach in the roofing and enters the house.

The process to fix the problem has two parts. First, the wet drywall and insulation must be removed and discarded. If left in place, significant mold growth is inevitable. Often some of the drywall on the ceiling will need to be removed. Plastic may need to be stapled up on the ceiling to separate the warm air in the house from the freezing temperatures in the attic.

Water will continue to seep in as long as the snow is there, so the cavity needs to remain open until the snow has melted from the roof. This will allow the owner to monitor progress and know when the repairs can occur. One to three months is not uncommon to wait until the repairs can confidently be completed.

The second step is to remove the ice dam from the roof. There are a couple of options available:
  1. Physically remove the snow and break the ice dam. This process is practical only on flat to lower pitched roofs. Even then, there is a great possibility for damage to the roof as well as the snow remover.
  2. Lay heat cable in a W pattern from the eve to at least one foot over onto the heated space. This will melt channels through the dam enabling the water to flow out and stop the damage. Check to ensure that the cable does not overlap or lay over on itself, as some cables will short out and stop working if this happens. Fires have also been known to occur from these situations.
The prevention of ice damming requires proper drainage of the melting snow. This is usually best done with heat cables run in a W pattern along the eve, up valleys and in gutters and downspouts. The key is to make it possible for the water to run clear of the house, even in the most extreme conditions.