This is the last column in the series Joy of Construction in Mexico and in it I would like to share some of the solutions to problems I have encountered over the past 10 years.
One of the more common issues that plague homes in Mexico is the smell of sewer gas in bathrooms. My first sewer gas challenge was in a brand-new home which smelled bad throughout whenever it was closed up for any period of time.
Many Mexican homes do not have properly vented plumbing for the waste lines, so that was my first thought, but after I researched that possibility it became clear I was wrong.
I filled all the traps with a mix of water and bleach, closed up the house and returned in the morning to find the stink still overwhelming. Next I pulled one of the toilets and examined the wax ring seal between the floor and the fixture. The seal was intact, but looked too flattened to be a proper seal.
It was then I realized there was no closet flange for the wax ring to “nest” on and when the fixture was installed, the wax ring had spread in two directions.
After a trip to the plumbing store, I learned closet flanges were not available in this part of Mexico. And since much of the waste line plumbing in Mexico is thin wall PVC in the P.I.P. (plastic irrigation pipe) format, a standard ABS closet flange would not work anyway.
Back at the house of stink, I took a six-inch section of four-inch PVC and made two lengthwise cuts a quarter-inch apart and removed the cut strip. I then squeezed the pipe until the cut ends touched and glued it inside the waste line with one inch exposed above the floor.
This gave me a flange for the wax ring to fit over and controlled the spread of the ring when the toilet was reinstalled. I repeated this process for the other toilet. Success! The house was then stink free.
Another common problem with Mexican houses is having hollow spots in the plaster which eventually leads to cracking and flaking plaster. The problem can be rusting and expanding rebar in the wall, or simply a matter of a poorly applied finish coat of plaster. I covered rusting rebar in my first column in this series, so now let’s take a look at poorly applied plaster.
North of the border a cementitious wall finish is called stucco when it is on the outside of a building and plaster when it is on the inside. Stucco or plaster is a three-coat process that uses metal lath to secure the first coat of plaster. The second and third coats of plaster require a certain moisture content in the preceding coat for proper adhesion.
In Mexico you can forget about lath or moisture content of successive coats, the subject just confuses the average albañil, and it is all referred to as plaster.
There are a couple of tricks for creating crack-free plaster that will last for many years. The first is using a concrete binding agent which is added to the plaster as it is being mixed. Then, a diluted mix of binding agent is painted on the wall immediately before the plaster is applied.
The other trick is adding fiberglass fibers to the plaster as it is being mixed. The fibers act like miniature threads which keep the plaster from cracking as it cures. Both the binder and the fibers are available in Mexico at Home Depot under the brand name Sika.
Also, most building supply stores will carry a concrete binder, commonly known as unicreto, and fiberglass fibers can be purchased at stores which specialize in plastic and fiberglass supplies. A bit of internet research on the use of these products will make your next plastering project a thing of lasting beauty. Oh, one last thing, make sure your albañil uses mortar, not cement, for his plaster mixture.
In countries with building codes and licensed tradespeople, laying tile is an art practiced by craftsmen who were trained as novices and worked their way up to journeyman status. Here in Mexico, everyone with a trowel claims to be el artesano de azulejo and most fall short of the mark.
Since tilework in Mexico is as ubiquitous as garishly colored houses, it is hard not to notice all of the attendant flaws in floors and walls wherever you look.
Of course, the classic we all notice is when a field of tile has tiny slivers of tile between a wall and the last full tile. This is caused by laying a full tile at a wall then running across the floor without knowing the size of the final tile piece against the opposite wall. The skinny tile problem can be avoided by starting in the center of the room and doing some simple math.
For an example, let’s take a room that measures 360 centimeters by 445 centimeters and tiles that are 30 centimeters square with a one-centimeter grout joint. Take half of 360 and divide by 31 (width of the tile plus the width of one grout joint) which gives you 5.81. This tells you that the center of the run will be a grout joint with five full tiles and 81% of a tile at the wall.
Now take half of 445 and divide by 31 which gives you 7.18. Since the remainder of 0.18 is less than half a tile, this run will require the first tile to be centered with six full tiles and 68% (0.18 plus .50) of a tile at the wall.
If this formula is followed you will never have a cut tile less than half a tile at the walls. Also, with larger pieces of tile at the walls, an out of square room will not be as noticeable.
I would like to thank my readers for all the comments and emails this series has generated. And I hope I have shed a bit of light on the perplexing tableau of construction in Mexico.
This column is the sixth and last of a series by Bodie Kellogg, who describes himself as a very middle-aged man who lives full-time in Mazatlán with a captured tourist woman and the ghost of a half wild dog. He can be reached at firstname.lastname@example.org.