View source for Low-Tech Solutions to Boost Low RH in Winter Climates

== What are the special requirements/recommendations for using the humidistatic method? ==

Any institution  considering the humidistatic control system must have an engineer work with them from the beginning to plan and set up the system. The engineer determines whether the system is viable for your situation and what additional measures need to be taken, if any, for its implementation. Experience has shown that the following recommendations are key to the successful use of this method.


=== Recommendations for humidistatically controlled heating technique. ===

:1. ''Use qualified specialists.''
:::Use an engineer who is familiar with humidistat control principles.  Include a good service contract with the firm that installs the system.
:2. ''Use a good quality humidistat.''
:::Less expensive residential humidistats lose their accuracy as soon as the RH falls below 35% and/or temperature dips below 50° F.
:3. ''Put one staff member in charge.''
:::The staff member responsible for overseeing the humidistatic controlled system requires training. This person must be in charge of the system at all times (i.e., heat cannot be turned up indiscriminately for human comfort, or doors left open).
:4. ''Ensure adequate air circulation.''
:::Good air circulation is critical to preventing condensation problems. Condensation and mold outbreaks are possible if cold air meets with warmer air. The engineer should determine if fans should run continually.
:5. ''Raise and lower the temperature slowly.''
:::When an object's temperature is much cooler than the air, the dew point can be reached and condensation can occur. Temperature should not change more than 15° F per day. Massive objects such as furniture retain or gain heat at a much slower rate (thermal inertia) than the surrounding air.  Covering furniture with muslin can provide a buffering effect against condensation.
:6. ''Raise large objects from the floor.''
:::Large organic objects, such as furniture, can trap moisture at the floor level.  A simple solution is to raise these items up on blocks.
:7. ''Remove objects from exterior walls.''
:::All objects hanging on or positioned against exterior walls have a higher risk of moisture condensation. Low exterior temperature transfers first through the walls of a building; upon meeting the interior surface, condensation can occur in poorly insulated structures.
:8. ''Use caution when moving objects.''
:::Some materials (for example -  furniture with hide glue joins) become more brittle at lower tempera- tures and require very careful handling until the objects become acclimated to a warmer atmosphere.
:9. ''Acclimatize objects gradually.''
:::Objects that are moved from a humidistatically controlled building/room to a normally heated space are subject to stress and condensation unless acclimated slowly. To alleviate this danger, objects can be placed in a sealed, clear polyethylene bag with a thermometer before relocation. Allow the temperature inside the bag to equilibrate to a higher temperature before opening the bag. This may take between 1 and 24 hours depending on the size of the object.