I was asked to look at a townhouse condo today. Owner was having condensation problems.
Here’s the gig: Outside walls are pacer panels, with stucco, windows were replaced in all units during the last 2 years, as well as all exterior doors.
Now… almost all units have water problems, the windows are puttin out water faster than Niagra. The drywall is spongy and there is mold in all the windows and on the baseboards.
This is onee unit, but I spoke with several tenants and walked around the buildings.
Anyone got any ideas as to why this is happening? or what can be done short of tearing everything apart?
Much thanks in advance.
Sounds like a flashing or wrapping issue.
Stucco and the scratch/brown coat(s) behind the it collect moisture and that moisture travels down and out away from the sill by way of a perforated flashing commonly called a weep screed. Without proper flashing and a barrier such as felt paper, house wrap, rain screen, etc, moisture will build up in and around the wall cavity, opening up possibilities for mold and wood rot. Because the stucco spreads this moisture and distributes it slowly, any opening in the flashing / wrap application allowing moisture usually isn’t detected right away, as compared to a roof leak where you can actually see it, and the damage is usually mold and rot. Proper flashing, especially around the window and door openings and where roof lines meet upper story walls are critical, along with proper wrapping and lath techniques.
It’s so important to allow that water to shed away and not into the wall areas by proper flashing and wrapping techniques.
Stucco and the scratch/brown coat(s) behind it collect moisture and that moisture travels down and out away from the sill by way of a perforated flashing commonly called a weep screed. Without proper flashing and a barrier such as felt paper, house wrap, rain screen, etc, moisture will build up in and around the wall cavity, opening up possibilities for mold and wood rot. Because the stucco spreads this moisture and distributes it slowly, any opening in the flashing / wrap application allowing moisture usually isn’t detected right away, as compared to a roof leak where you can actually see it, and the damage is usually mold and rot. Proper flashing, especially around the window and door openings and where roof lines meet upper story walls are critical, along with proper wrapping and lath techniques.
It’s so important to allow that water to shed away and not into the wall areas by proper flashing and wrapping techniques.
Air exchanger comes to mind, try Plusaire, Tony Baptist is the owner and desiner go to www.plusaire.on.ca hope this helps, tell him I sent you.
How old is the house, how is it heated? Are the replacement windows vinyl, metal, wood? Exhaust fans? How many are in the townhouse (occupants)?
Whats the grading like?
What conditions did you see in the attic?
These townhouses are approx. 20-25 years old. They are heated with Natural Gas. The windows are vinyl clad and the doors are wood frame-steel door. At the rear are vinyl-clad sliding patio doors.
The grade slopes to the rear, away from the townhouses.
There are 5 occupants in this unit, various numbers in the others.
That might be your answer; 5 occupants all bathing, cooking, breathing with new, tighter windows.
Charles has a good idea, but I would be inclined to open some windows and get some cross ventilation for a few days, and then see if it redevelops.
Ray…all the units are like this, be it 2 people or 5 people in them.
Then it sounds like Charles and Dave have come up with the right answers. If the humidity is as bad as stated the attic most likely would be exhibiting mildew/condensation/mold to?
I believe that the relative humidity should be kept below 40 percent during winter months to avoid mold problems.
If exhaust fans are installed are they being used? Are they installed? Do they work? It also could be the townhouses are too tightly constructed.
More thoughts, it really could be a variety of factors.
Tony of Plusaire will leave a canister behind to find mold in the home , if you look at the system it is different than most!!
Brian, Check your private messages
After very breifly looking at the site, It appears to a supply only system not an exchanger. If the house requirements are 40 cfm or more I would rather see a balanced HRV or ERV rather than an supply-only or exhaust-only system
You are taking an older leaky home and tighening it up. The natural air exchange that you had with the old windows is gone. Even the best windows in the world will condense if the humidity is too high. You need to measure the humidity in the house, it will have to be below 40% in realy cold weather to prevent condensation. At -18C to -24C it should be 25%
Check this out for recommended humidity levels
http://oee.nrcan.gc.ca/keep_heat_in/chapter_8/chapter_8_2.cfm?PrintView=N&Text=N
Thank-you all. I have printed out all replies, links, and pm’s. I will hand these to one of the owners tonight.
Again, much thanks
You say the heating system is natural gas. I assume each unit has it’s own forced air furnace. If so then is there a fresh air vent and a combustion air vent. These are vents that run from the outside to the cold air return and the other provides oxygen to burn the gas. Since these units are over 25 years old they may not have these vents. They should be installed otherwise you can get back drafting. Installing a HRV (Heat recovery vent) or air to air heat exchanger. The HRV pulls fresh dry cold air from outside, runs it through a heat exchanger that takes the heat out of the inside warm wet air as it move it to the outside. HRV provides dry fresh air to the inside and moves the inside warn moist stale air to the out side.
The HRV would be inserted into the fresh air and combustion air vents.
Brian , I sent Tony your message and here is his reply,
Hi Chuck,
Thanks for the refer, how do I get into touch with them.? The problem is simply a lack of adequate ventilation. We have fixed up town houses before and the ones in the middle are the worst owing to there being only effectively two outside walls which classes them as very tight. I did four in the same sub that’s on east Colborne Street. They were typical and Plusaire fixed them overnight. If there is visible mould I would suggest the ultraviolet model. The UV will not only clean the air but purify the air as it comes out of the rugs, curtains, furniture etc. It takes a bit longer to do this but the mould never comes back.
Regards
Tony
Open the windows in the meantime and get some cross ventilation. The windows would only have to be open an inch or two.
[quote The UV will not only clean the air but purify the air as it comes out of the rugs, curtains, furniture etc. It takes a bit longer to do this but the mould never comes back.
Regards
Tony[/quote]
My understanding is that this UV system is not proven to work. Is there evidence to prove otherwise? I’d be very interested to hear more. Doug
Ozone