During summer, I run a fan and a dehumidifier 24/7 in the basement. Without them, the smell is stinkier than just musty. @Midwest67 If you use an ozone machine, is the fix long lasting, more than a year or two?
BB where we live they give 40 years on cedar roof.
40 years means it is old growth stuff, but there is NO guarantee or any warranties on natural products. Thus, 40 years is an estimate as to how long it woukd last in ideal conditions (no rain, perfect himidity, no debris etc…) There are cheaper ones… Like the roof our neighbor had. It had to be replaced after 14 years even though the guy meticulously maintained it. So if your roof is 20 years old, you probably got the last bundles of the good stuff. Not the flimsy stuff they call cedar shakes nowadays. The old growth forests have been pretty depleted.
I would get the roof cleaned, some of what you are smelling is likely that. Does it smell musty in the attic? It could be you have a problem up there, where mildew is growing inside as well. One thing to try if you can access the attick would be to paint the inside with a mildew killing primer, I did that when I had mildew in an attic because of moist air from a humidifier getting up there (won’t happen any more I suspect, both my attics have a ridge vent and open soffits to allow air to circulate better). You potentially also could get someone to install a vent fan in the attic, but make sure that there is enough fresh air intake, you don’t want it creating a negative pressure situation up there.
With the basement, that likely is because there isn’t enough air circulation there. You might for one need more dehumidifiers there, do you have a humidity gauge in the basement? My basement is small, and I have a 70 pint dehumidifier going (it drains into my sump system) and it keeps it well under 50%, but with a larger basement you may need more capacity. The other thing is if the basement isn’t finished, you may want to paint the walls and the floor with drylok paint, if you don’t have a big water problem that can help seal the wall and floor, which for one thing will trap any smell from active mildew and also will keep water vapor from seeping in through the walls.
You also could do a home version of the things they advertise on the radio, 'the wave’s system and such, what it basically is is a vent fan (like you use in a bathroom) that vents outside, and it creates negative pressure in the basement that brings drier air down from upstairs. There are some things you have to be careful with this, negative pressure could cause it to suck CO back from the output of the hot water heater or cause an issue with a standard vent furnace (wouldn’t affect a high efficiency one I believe), but is a lot cheaper than what they charge for those systems. You could put it on a timer to run a certain time each hour, or on a humidistat.
Probably no need to power wash if you can get up on roof yourself. Just mix up a cup of blue dawn with a couple gallons of water and spray on roof. Mildew and mold should turn brown within a day and die. Works in your yard too without killing the grass. Blue Dawn dish detergent is a miracle worker in so many ways.
The roof is too steep for me to get up on. Simply not cost effective if there’s an accident.
I’m not sure re: how long an ozone machine cleaning lasts.
You run a fan in the basement, but is it just circulating the stale air? Usually, the first line of advice is the easy stuff. Is there a source of fresh outside air, eg, as simple as an open window? And consider musicprt’s wisdom that the dehu may not have enough juice going for the cubic size of the space.
In summer, recirculated air is less humid than fresh outside air. In winter, fresh air is too cold. It’s an old house not very air-tight anyway. Yes, if I open the window, the smell goes away. How do you keep the window open in 90 degree heat 60% humidity in summer and 20 degree cold in winter? I use the fan to bring the air to the dehumidifier. I did experiments. With the fan on, the dehumidifier worked better; more water was discharged from the dehumidifier. I thought about getting a second dehumidifier last spring. When I checked the specs, the humidifier I have covers twice the space I have. Of course, the specs could be wrong.
@igloo:
There is another option for the basement, but it would be expensive. You can get an air exchanger for the basement, what it basically does is takes air from the basement and replaces it with outside air, and it has a heat exchanger so in winter, the outgoing air heats up the incoming air, and in summer outgoing air cools down the incoming air. Humidity could still be a problem in summer, but a dehumidifier would help with that. Won’t be cheap, but it is an option since it is giving you the air circulation you want/desire down there.
We have a pool house that always had a musty smell, and it was a pretty new structure. Low and behold we have a huge storm and the basement flooded. We called serv pro to come clean up the mess - they tore out the floor, and chunks of dry wall, where there was mold. Since they did that the smell is completely gone. Based on how the wall was we too it wasn’t draining properly.
Musty means something is wet, and potentially moldy. I would try and make sure there isn’t mold and water behind walls.
I agree with @eyemamom, a musty smell means something is wet. Mold or water behind walls can cause a lot of problems in the long run. You probably have a leak somewhere – possibly a leaky roof or possibly a place where flashing is not working properly. Also, you may have downspouts which are dumping water next to the house which is running into the basement or even worse into the walls.
I think that you need to find the source and fix it or get it fixed. Servpro and other professionals have tools that they can use to measure moisture behind / inside walls.