Generally, DIY can save homeowners money. For example, HomeAdvisor reports that a homeowner who chooses to install their own linoleum flooring may save as much as $5,000 compared to a homeowner who hires a contractor. However, some projects are simply too complex, involve too much risk and require too much specialty knowledge for homeowners to DIY.

Damage from Smoke or Fire

Smoke and fire can do terrible damage to a home. Smoke damage can affect everything from clothing to upholstery, carpet and the very walls of the home.

While homeowners can use specialty cleaning products to remove soot, and can replace drywall relatively inexpensively, odor removal requires specialty tools that can be expensive to purchase and difficult to rent. Thermal fogging and ozone treatment are two of the most common methods that professionals use to remove the smell from a home.

A typical homeowner will pay between $3,000 and $22,000 for smoke damage restoration, yet performing the DIY project may be even more expensive. If the homeowner's efforts fail, hiring a contractor afterword to finish the job could make the effort more expensive than if the homeowner had hired the contractor in the beginning.

Damage from Wind

Wind can damage everything from the home's siding to roof. Repair work can be extensive, and many DIYers take much longer than contractors to make repairs. During that time, the home is vulnerable to damage from rain and the other elements. Homeowners who try to repair their own roof or siding may save on labor but could cause other costly problems while fixing one problem at a time.

The advantage of hiring a contractor for this work is that the contractor has all the tools on hand to fix the job and will likely have a crew of people as well. Whereas a damaged roof and siding can be repaired in a weekend by a contractor, a homeowner could take many days or weeks.

Wind damage can cost between $2,000 and $10,000 to repair via a contractor. Homeowners hoping to save money can do some of the work on their own. For example, the homeowner can cut fallen tree branches to a more manageable size, then may haul them away to save on clean up costs from the contractor.

Earthquake Retrofitting

This type of project requires a lot of specialty knowledge about a variety of systems in the home. Retrofitting takes place in the basement or crawlspace and up into the exterior walls. Earthquake retrofitting is done by bracing the walls and by anchoring the home to the mud sill or bolting the foundation, whichever is appropriate.

The cost to earthquake retrofit a home is approximately $4,000. However, if the efforts fail, the home could be seriously damaged or completely destroyed. Foundation repair after an earthquake can cost as much as $25,000, while the replacement of the entire home is far more costly. The best way to ensure that the home will survive a major earthquake if one happens is to hire a contractor.

Mold Damage

Mold is a serious problem that often occurs after a flood. Water damage after a flood can cost between $1,000 and $4,000 to repair, with mold remediation being a large part of that. Angie's List reports that mold remediation can cost between $2,700 and $3,300. Mold remediation costs over $500 should be handled by a licensed contractor because mold remediation can be invasive and could potentially do damage to the home.

Mold remediation involves an assessment of the home, contamination control, source removal and moisture control. This multi-faceted project must be comprehensive, or mold will return.

Homeowners who aren't sure about a DIY project can contact their contractor for more information. Speaking to a contractor can help the homeowner get a sense of how much a project will cost and whether it can be completed as a DIY.