It may not seem too difficult to install a new kitchen sink or a dimmer switch for your dining room.
But when that sink won't stop making awful gurgling noises or that dimmer box winds up melted, many homeowners find themselves going to a professional.
"We quite often and go in and when we're tearing things apart we witness things that homeowners have already attempted themselves," said Mike Crossman, the owner of New View Design and Remodeling in Cleveland. "If no one gets hurt, it's quite comical in a way."
One homeowner installed plumbing too close to their walls. When a carpenter later installed a doorframe, the nails punctured the pipes, leading to some strange leaky walls.
But other DIY-projects have had much more damaging results. When one homeowner's deck collapsed, the barbecue on the deck fell eight feet onto people below, spilling charcoal and burning them.
That doesn't mean there aren't home improvement projects where a little sweat equity will save you money and hassle. What you should do - and what you should leave to the professionals - depends largely on how safe the project is and how costly mistakes are to fix.
What you should not do on your own
Unless you're fixing a drain or unclogging toilet, there aren't a lot of plumbing projects you should DIY. Messing with the plumbing can lead to expensive mistakes. A sudden pipe burst can fill your home with water in minutes. Plumbing that's not properly tested can leak and pool, causing water damage and an even worse problem, with possible several health consequences - mold.
Decks. "Decks seem like something people can do on their own and a great project to get underway on the weekend," Crossman said. "But decks have collapsed and it comes from not having that experience how to properly attach the deck to the house."
The problem with decks is that they can and do collapse, and cause major injury and damage.
Electrical. There are so many electrical codes you have to follow when installing your own electric that it's even hard for electricians to keep up. Improperly installed electric can cause fires at any point, putting everyone in the home and the home itself at risk. You're even at risk during installation, when a major shock could kill you.
Demolition. "We often get asked, 'Well, hey, how much can I save if I do the demolition myself?'" Crossman said. "They see people on TV running sledgehammers through drywall and it all seems fun."
But Crossman has seen too many things go wrong during demolition and more often than not, they're hugely costly to repair.
One homeowner was ripping out cabinets when he broke off the water shutoff valve, blasting water out of the pipes. By the time the homeowner got to the basement to turn off the water, his basement and first floor was flooded with water.
What you can do yourself
Painting. The worst thing that can happen when you paint yourself is a bad paint job. Use plenty of painter's tape, ask about a good primer and buy enough paint. You might even want to watch a few YouTube videos to get some tips on technique.
Tiling. While you need to be patient and exact with tiling, a vinyl tile floor is certainly possible to do yourself. A tile backsplash will add value to your kitchen and is such a small job that you'll pay a premium for a contractor, Crossman said.
Drywall work. While installing large-scale drywall may be too much for some homeowners, others are perfectly capable of tackling this project. Start with a small space, like a bathroom, and see how it goes. And anyone can patch some drywall. It just takes patience and a small flat spatula.
Installing trim. "Try trim work," Crossman said. "The worst that you're going to do is cut some pieces short."
Consult with people who have done this project before, make sure you're level and you've cut the right size pieces, and this is a project most DIY-ers can tackle with relative ease.