Building Basement Apartment
Condensation and Mold Control in Buildings/homes:q&a
QUESTION: I am a little confused. You say that one of the measures to control internal humidity during the heating season is to ventilate. How can it be possible?
Exterior relative humidity most of the times is higher than interior R.H. Sometimes it is as high as 95-98%.
ANSWER: The misconception is between the meanings of the terms “absolute” and “relative humidity”. In order to achieve “dilution” of interior humidity we need external air drier on an absolute basis. Relative humidity as an index sometimes could be misleading because it strongly depends on temperature.
Let’s see a small example to make it completely clear.
In our beautiful Thessaloniki, North Greece, it’s not a rare phenomenon to have outdoor temperatures near 0oC. This means that even for a R.H. of 100% the absolute humidity or moisture load is 4,8gr/m3.
Coming to the interior rooms…
For an average temperature of 22-23oC the absolute humidity is about 14gr/m3. This is a much bigger number.
Actually for the heating season this is always the case: indoor absolute humidity is higher than outdoor. This means that by ventilating we can always achieve “dilution” of the interior humidity.
QUESTION: What is the most effective measure to prevent/control mold growth in home?
ANSWER: Mold growth is a moisture related problem. When you control moisture, you control mold growth. Potentially there exist many moisture sources etc. roof, façade and basement leaks, pipe leaks, moist air infiltration etc.
Humidity produced from every-day indoor activities is by far the more important moisture source under normal conditions.
So, do your best to reduce production of humidity by abstaining from certain “bad” habits (as for example drying clothes inside).
”QUESTION: I don’t have any condensation or mold problems in my wet rooms. No problem also in the room where we usually dry our clothes on the radiator. But I have problems in other rooms with no vapor production activities. Why?
ANSWER: Firstly we have to stress that water vapor can travel easily from room to room via open doors. So relative humidity can soon be equalized. Reasons for which condensation and mold develop in this special room might be:
1. This room is not ventilated properly.
2. This room is underheated.
3. This room has an unfavourable orientation.
4. And the most probable, there are thermal bridges in the external walls.
Other factors to consider:
- Are there some plants in the room?
- Is this a much-frequented room etc?
QUESTION: There are two identical apartments with the same orientation. I have mold and condensation problems whereas my neighbor who lives one floor above me has practically no problems.
ANSWER: Please check the previous answer. The apartments are identical in form but not in prevailing conditions. Possible differences (except for the above mentioned) could be:
- more people inside your apartment
- a baby maybe?
- adolescents who have baths 2-3 times on a daily basis
- clothes drying indoors
- unvented gas or kerosene heaters etc.
The moral is that two apartments however identical in construction terms, will always have marked differences in their prevailing conditions.
QUESTION: Can we alleviate mold and condensation problems by intervening externally?
ANSWER: If you mean some waterproofing measures, definitely no. The only possible external intervention could be the addition of some extra thermal insulation. Of course this could be done also from inside.
I ‘ve seen a lot of money thrown out of the window trying to solve these problems by external waterproofing.
Chris Strogilis
http://maconwaterproofing.blogspot.com/
About the Author
Civil engineer with postgraduate studies in MBA and Marketing
Apartment building basement fire
|
|
Honeywell RCWL300A1006 Premium Portable Wireless Door Chime and Push Button $31.94 The Honeywell RCWL300A P3 Premium Portable Wireless Door Chime and Push Button makes it easy to replace your home’s generic doorbell ring with a chime tune that better fits your individual style. This chime is also compatible with a wide range of optional security accessories that can help you safeguard your home and family, and it comes complete with a pre-programmed bell push button. .caption … |
|
|
Honeywell RCWL330A1000/N P4-Premium Portable Wireless Door Chime and Push Button $44.94 A premium door chime from Honeywell with the option of adding on security accessories offering peace of mind and custom upgrade possibilities. Add-on push buttons for other entrances around the home, door and window contacts for added security, or motion detectors for peace of mind inside and out. The RCWL330A incorporates six (6) visual alert icons to let you know which device has been triggered … |
|
|
IAQ Pro 5-Minute Home Mold Test (Aspergillus, Penicillium, Stachybotrys) $34.95 Concerned about black molds in your home or office and need immediate results? Why wait 48 hours for a culture dish to incubate? Why wait another 7 days or more for a lab to tell youu what’s on the culture dish and pay additional fees of $30 or more? The IAQ Pro 5-minute Home Mold Test provides rapid and sensitive identification of the most worrisome molds associated with water damage. Unlike othe… |
|
|
DampRid FG50T Hi-Capacity Moisture Absorber, 4-Pound Tub $9.99 … |
|
|
D-force HPX 14 oz Can D-Force HPX has the power of Deltamethrin for above ground termite control, bedbugs, plus 50 other species! D-Force provides 100% control of crawling insects for up to 8 weeks. 14 oz. can. KILLS: Ants, Bees, Bedbugs, Carpet Beetles, Centipedes, Cockroaches, Crickets, Firebrats, Fleas, Flour Beetles, Grain Beetles, Ground Beetles, Gnats, Midges, Mole Crickets, Moths, Pillbugs, Silverfish, Sowbugs, … |
|
|
Root Cellaring: Natural Cold Storage of Fruits & Vegetables $8.48 Anyone can learn to store fruits and vegetables safely and naturally with a cool, dark space (even a closet!) and the step-by-step advice in this book. … |
|
|
In-laws, Outlaws, and Granny Flats: Your Guide to Turning One House into Two Homes $14.96 In response to tight times, a remarkably upbeat and widespread change is taking place in households across America. Homeowners are creating second dwelling unitsâoften called in-law suites, mother-in-law apartments, or granny flats. Second units make a lot of sense. They’re perfect for families who want several generations living close by, they enable Baby Boomers to care for elderly pa… |
|
|
The Complete Root Cellar Book: Building Plans, Uses and 100 Recipes $12.41 Nature’s way of storing fruits, vegetables and preserves. Whether as a way to manage challenging economic times or retain a garden’s bounty, root cellars are making a big comeback. This book takes a fresh look at the art, science and romance of building and stocking a root cellar. There are detailed illustrated construction guides for making four different kinds of root cellars that are functional… |
|
|
The Divide $3.99 … |
|
|
The Divide $14.99 … |
