Bad smells in your house?
Question:
Hey folks. I can use as much help as possible with these issues.
(1). We plan to look for a house to buy this year, in or near the Centro area of Mazatlan. A couple of years ago, we rented a house on the edge of Play Sur. Every few nights, we would be awakened by a horrible stench eminating from the bathrooms. Turned out to be sewer gas coming up through the drains. Nothing we tried eliminated this problem. One person I spoke to said that this was a common problem. I also saw a post on an internet forum which indicated the problem also occured in an upscale property in the Golden Zone. Does anyone know how common this problem is and whether or not there are solutions.
(2). I recall someone saying that several houses in Playa Sur were susceptible to having sewage backups during the rainy season. Does anyone have information on the valid and prevalence of this issue?
Answer:
I learned a lot about this problem when I built a bathroom for a friend many, many years ago. The town inspector took one look at my work and said I needed to do some reading before I did any more plumbing work. That was being kind.
The problem here is really the same as everywhere else. You need to have a physcial barrier for any opening in the waste water system in your house. That barrier is easily created with water, but you need to have traps in the sink and shower/bath to provide this barrier (toilets have a trap built in). Our house had traps in the sinks, but no traps in the showers.
In addition, you need to have a way for the trapped gases (assuming you have the traps in place) to exit your house. Its called a vent or soil stack. If you look at the roofs of houses in the US, you will almost always see these PVC pipes exiting the roof. This way the gases vent into the open air above your house as they rise from the sewer system. All states in the US require traps and vents as part of standard plumbing code.
Most Mexican homes have neither traps (especially in the shower/tub) nor vent stacks. Traps and stacks are cheap and easy to install during the initial construction (for 2 bathrooms we might be talking $200 in additional expense). They are pain in the butt to install after the house is built, but it can be done.
The problem is particularly bad in Centro/Playa Sur where the sewage system is inadequate for the amount of waste running through the lines. Yet, another plumbing item missing in most Mexican homes is a backflow device to prevent the sewer system from backing into your home during a heavy storm or rain (actually these devices aren't used in the US much either). During the rainy season some of our neighbors did have sewage backup in their home.
Flooding is definitely something to be aware of when you purchase a home in certain areas. Not all homes will have a flooding problem if they are built sufficiently above the street level or if there is no plumbing on the ground floor (its all about gravity and air pressure). We like to joke that when we bought our house we didn't know we had purchased riverfront property - we might have had to pay more! In some areas, the water in the street can be waist deep during an average rain during the season.
Below is a picture of a trap and waste line. The water trapped below the tub prevents gas from escaping into the house.
I have fixed the bathroom in the main bedroom, but not the guest room. It keeps guests from staying to long.
DavidShafer May 4, 2005