Most areas in the U.S. are subject to natural disasters that can damage homes. When the damage is done, should the home be rebuilt or demolished to make way for new construction?
The home pictured above burned the Friday after Thanksgiving in 2014. RTA published a blog post about the home and some steps to prevent fire losses. That home is being “repaired”.
The fire significantly damaged the home to the point the roof collapsed. The fire department pumped in so much water it flooded through the home and down into the basement where it collected – that’s not unusual in structure fires.
Other natural disasters like hurricanes, tornadoes, floods and earthquakes can cause similar damage. In many disasters, the structure of the home is compromised and the building (houses are buildings) is opened to the weather so water damage occurs. Can damage from a natural disaster be repaired?
Repairs from Bottom to Top
Repairing a damaged home starts with the structure – the foundation and framing that support the home. Repairing a structure always starts at the foundation, where the most load is carried, and goes up to the top where the least load is carried. If the structure is in good shape or can be repaired without significant work, the home has a chance of avoiding demolition.
Repairs from the Outside to the Inside
Once the structure is able to support the home, the building needs to be enclosed to keep the elements out of the interior of the home. When a house is built, its enclosure (the continuous barrier of the floor, wall and ceiling assemblies that keep out the elements) should be carefully installed so the enclosure is continuous. If there are gaps or holes in the enclosure, air and water leak in and out of the house.
When there are holes in a building enclosure, it’s expensive and difficult, if not impossible, to control the interior of the house with heating and cooling. A home with a leaky building enclosure can waste a huge amount of energy trying to heat and cool the interior of the home because the interior is connected to the outside through those leaks.
The Elements of a Building Enclosure
The building enclosure of a house is made up of control layers. There are four main control layers for any building enclosure. They control the flow of water, air, vapor and heat.
You’re already familiar with at least some of these, even if you’ve never thought about it in this way. For example, the winter we lose the heat in our warm homes to the cold outside. In the summer, we gain heat from the hot outdoors to our cool (air conditioned) indoor spaces. We use insulation to control that flow of heat so the insulation is a thermal control layer.
The control layers must be continuous to form a tight building enclosure. If there are gaps or openings in the control layers, they fail – they don’t control what they’re intended to control. Failures in the control layers can allow water, humidity and air in and out of the building. When there are leaks in the building enclosure, you don’t have control of your home’s indoor environment. Humidity, dust, allergens, air pollutants and pests may enter and leave your home through those leaks.
Building a House
When a house is built, the contractor has access to the control layers before they’re covered by whatever material is on the outside of the house. The contractor can even hire a verifier to test the home to determine if the control layers are continuous. Testing the home helps find any significant gaps or leaks that need to be sealed before the exterior finish like brick or wood siding is applied and you no longer have access to the control layers because they’re covered.
The Concerns Are Many
The building enclosure of a house can be severely damaged by a natural disaster. That damage may cause failures in the control layers that can only be repaired by removing the exterior cladding of the house to gain access to the control layers and make repairs until the control layers are continuous.
In the case of this fire, it’s difficult to tell if the fire burned hot enough to damage the control layers behind the brick – they can’t be seen from the inside of the exterior wall assembly. It can also be extremely difficult to connect the new control layers to the old control layers without removing some of the existing construction.
As you can see in the image above, the repairs to this house are being done from the inside. They haven’t removed any of the cladding so they don’t have access to the control layers between the wood framing and the exterior brick. You can probably guess the consequence of rebuilding the structure and interior of this house without paying attention to the control layers. It will be extremely difficult to control the interior of the house.
That means this house will likely be:
1) Unhealthy – holes in the building enclosure allow humidity, dust, allergens, air pollutants and pests in|out of the home,
2) Uncomfortable – too humid in the summer and too dry in the winter, and
3) Inefficient – the heating and cooling systems will struggle to keep the interior comfortable since the inside of the building is connected to the outside through leaks.
Who’s Watching Out for the Home Owner?
It’s awful to think the owner of this house was probably never presented with these issues when discussing repairs to the house with his|her project team. It’s worse to think the owner decided not to worry about them and intends to sell the house once repairs are completed.
A home inspector may or may not find enough clues to take a closer look and discover an incomplete building enclosure. If you bought this house after it’s rebuilt, you’d have to deal with health, comfort and efficiency issues.
Where’s the building official? Why isn’t he|she stopping this? Not all repairs require the house to be brought up to the current building codes. If this work falls under the requirements for updating the building to the current codes or the work is being done without a building permit, the contractor has significant leeway in decisions about what to do and what not to do. Also, not all building officials understand the importance of continuous control layers so they pay more attention to other things like the structure.
If you’re rebuilding after major damage, don’t take the details for granted. You never want to invest good money in a bad project. Find a qualified professional who can present the issues and possible design solutions so you can make the best possible decisions before spending any money on construction.
A home energy rating on this house would probably reveal the major issues that might get past a home inspector. If you’re worried about buying or renovating an older home, don’t panic. There are a significant number of variables to consider when decided whether a home should be renovated/repaired or demolished. You can find a qualified professional to help you evaluate any home and discuss your options. It’s up to you to build the right project team to build your project.