In this series, master craftsman Daniel Westbrook interviews industry expert Mark LaLiberte, founding partner and president of Construction Instruction. Mark has been educating the building industry on the science and physics of construction for more than 30 years, and sharing the benefits of constructing durable, energy efficient, healthy homes. 

Can we make modern buildings last hundreds of years? 

We obviously have the knowledge and skill to make buildings last 200 years, but the question is, is that what we want? A lot of things have changed over time—for example, we see more ADUs these days, and we may see houses get smaller as we realize we don’t need so much house. But I would say, most of all, we’re likely going to see more factory-crafted houses—modular homes built in a controlled environment rather than on a construction site—brought on-site to build. 

Our industry hasn’t gained a lot of productivity in the past hundred years, so I think we will see some evolution as businesses build houses more efficiently. I know we have the knowledge to make them last, if we want them to.

What are some of the biggest mistakes you see contractors make?

I’ve seen people forget about the water heater and the furnace—they say, “We replaced that five years ago, so I think it’s fine”—but the water heater and furnace both draft naturally, so if you do a retrofit and put in a new kitchen arrangement and turn the fan on, it sucks the air out of the building, which pulls the flue gases back down. If you’ve got a children’s room downstairs, for example, you put them at significant risk. 

So combustion safety, I think, is as paramount as anything. We call the test for that "worst-case depressurization." You turn on all the fans in the house, then go downstairs and make sure the water heater and furnace are properly venting. You can do that by turning the thermostat and hot water on, then making sure they properly vent—it should always re-establish a draft. If it doesn’t, it’s an important thing to remedy immediately. 

Is it the responsibility of the contractor to educate the homeowner on what can happen? 

Before I go to the doctor, I do my homework so I know what’s going on, but I’m not going to tell them what to do. Similarly, I think it’s the contractor’s job to have the knowledge and experience to come in and say to the homeowner, "Let’s lay out how this project will go, and from there, we’ll make decisions together."

That said, I think it’s important for the homeowner to do their own research, too. An informed contractor plus an informed homeowner always make projects go more smoothly. 

Stay tuned for more on energy retrofitting from Daniel and Mark—and be sure to check out the full energy retrofit series here.