This column was inspired by two expensive mistakes, one by a home builder and one by a home-service installer. In both instances, an hour or two of extra time and a few extra dollars spent on materials would have saved thousands of dollars in repairs down the road.

Last week, a homeowner who lives just 10 miles from me hired me to do an in-person consultation at his house. Water was leaking into his basement over the top of his foundation wall.

(I’ve done consulting like this for years, and my most exciting consult of all time had me walking all over the roof of the Brazilian ambassador’s house on the island of Antigua. I shot a video up on that roof that was later introduced as evidence in a trial.)

In just minutes, I discovered the source of the leak at the local homeowner’s house. Whoever built the deck attached to the back of the home made mistakes. He also made a basic and serious mistake when installing the sliding glass door that leads from the house to the deck.

The deck was attached to the house with a few lag bolts. This is a mistake, because lag bolts can be overtightened and have minimal holding power. Moreover, the treated lumber board against the house that supported half the deck’s weight had no flashing at all. The decking boards were installed so they touched one another, with the result that rain and snowmelt water couldn’t get down to the ground quickly. Instead, because the deck was out of level, the water drained toward the house.

The sliding glass door didn’t have a flashing pan under it. When I went into the basement and pulled back the fiberglass batt insulation that was on top of the foundation, I discovered rotten subflooring under the door. The band beam joist that sits on top of the foundation was so rotted I could scrape out large chunks of wood with my fingernails.

The roof also had no gutter on it. Many here in the Northeast think it’s a bad idea to have gutters on homes because falling ice and snow rip them off houses. That’s true if the gutter is installed wrong and there are no gutter guards on the roof. I’ve had gutters and the best gutter guards on my home for years, and tons of snow and ice cascade down from my roof after each storm. Because my gutter hangs below the slide plane, the snow just slips over my gutters and down to the ground.

Because there’s no gutter on this man’s home, each time there’s a significant rain event, hundreds of gallon of water splash onto his deck and run up to his house. Snowmelt causes the same problem.

When his deck was built, it would have taken only about two hours of work and $50 worth of material to prevent the leakage problems. I sat at his dining room table and made a list of all the products his builder should have used. I also made a crude drawing showing how the deck board should have been installed with all the proper flashings and products.

You can get the list of all the best products by going to this location at my website. A link to a better color drawing showing how the deck board should have been attached is available in this free document.

When I got home from the consultation, my local septic tank pumping company had just finished troubleshooting why my effluent ejection pump alarm sounded. They had to pump out my septic tank and the second smaller tank where the pump is housed to make the repair.

A technician asked me if we had a water softener that drained into the house drain lines. “Why, yes, we do,” I said. “How did you know?” The wise young man noticed that there were far too many solids, including undigested toilet paper, on the wrong side of the input baffle inside the tank.

When the water softener regenerates, it discharges very salty brine into the septic tank. This salty brew kills much of the beneficial bacteria that digest many of the solids. The secondary effect of this is the water entering the leach field has too many tiny solids. The tiny solids cause the leach field to fail. It costs thousands of dollars to install a new leach field.

The workers who installed the water softener in my home should have chosen a better option: simply drilling two 3/4-inch diameter holes through my fiber cement siding. The discharge brine could easily have been ducted out of my home and into a nearby drain pipe that carries storm water down and away from my home.

Fortunately for me, this workmanship error was caught in time and I don’t have to install a new leach field. All it cost me was the price of pumping the tanks.

Workmanship errors can cost you a lot if they are not corrected. If you need me to help you troubleshoot potential errors, I can almost always do it. All you have to do is ask. Visit my website and click the Ask Tim link at the top of each page. Let’s start a conversation!

Need an answer? Tim Carter can call you on the phone to solve your problem. Go to his website and fill out the form on this page: