Asked on May 13, 2018

How can I build a roof over outside AC unit?

Anne Berry
by Anne Berry
My outside HVAC unit is directly under the dripping from the roof. In winter, a big ice ball will form inside it. I have also had to sweep a foot of snow off it with a broom. Last winter, I rigged up a roof from a dog house over the unit, about 2 feet off the top of the unit. I would like something more permanent.
  17 answers
  • Cheryl A Cheryl A on May 13, 2018 hope this helps

  • JoeStatenIsland JoeStatenIsland on May 14, 2018

    Anne, You really don’t want to obstruct air flow from your condenser unit. I am familiar with the unit you show in your photo. The more air flow you have above (this is an up blast design) and around the sides, the more efficiently it will operate. By the way, clean the coil regularly with a good condenser coil cleaner. These units are engineered for the outdoors. First off, they do sell covers for these units for the winter time. But my question is “what is dripping/leaking from above?” It looks like the beginning of the pitch of your roof gutter. You probably have a separation in the end cap gutter seam. That is easily rectified with a tube of high quality outdoor sealant available at a Lowe’s or Home Depot. I would start by correcting the drip which is the cause of your concern. Good luck. ... Joe, Staten Island

  • Jeanette S Jeanette S on May 14, 2018

    You can build an open pavilion type covering a little larger than the AC and leave all 4 sides open...make sure the roof is not too close to the top of the unit so as not to impede air flow.

    You might want to dig down a few inches around the unit for about 6" wide ditch and fill it with rocks (you can buy these by the bag in the landscaping dept of the big box stores)...this would sort of act like a french drain...rainwater would not slash up mud and make a mess on the ground, nor puddle.

  • Cha13615598 Cha13615598 on May 14, 2018

    fix the leak dont cover the ac...flex seal fasl and easy

  • Cath53 Cath53 on May 14, 2018

    Why not simply buy the vinyl cover that fits over it for the winter?

    • Steve Steve on May 15, 2018

      Yup....a cover for the winter is the answer and I’ll bet York has one that will fit your unit exactly. I always cover my AC in the winter. Just remember to take it off in the spring.

  • Itsmemic Itsmemic on May 14, 2018

    I guess I am going to repeat...why not just buy a vinyl cover?

  • Chris Chris on May 14, 2018

    According to my heating guy, you should not cover AC. For winter, he told me to put a piece of plywood on top with a brick to hold it down.

  • Nancy Turner Nancy Turner on May 14, 2018

    By the time you use your A/C the ice should be well gone. Cover it for the winter. The summer rain is taken into consideration when the units are designed. If you build around and over the unit you may void the warranty.

  • Ellis Ellis on May 14, 2018

    A/C units need lots of room while they're running, so don't cover it, as others have already said. Get the gutter fixed for summertime, and in winter just cover the unit on top so snow/rain/sleet are kept out. My A/C mechanic said not to cover whole unit with plastic cover over winter as it prevents air flow and promotes rust.

  • Ann Ann on May 14, 2018

    We have heat pumps around here as there isn’t any natural gas lines and propane is quite expensive. Heat pumps supply both heat and air. At a previous house where I had the problem of roof run off icing up my unit in winter, I had an open style arch / trellis like structure that went over the path at the side of the house. this structure just happened to be beside the heat pump. Structure was about 3 feet wide. We bought a piece of that clear ridged material that people often use for skylight in a shed. We nailed a piece of this over the end with the heat pump. It sat about 5-6 feet above the heat pump and solved our problem. I wish I could send you a pic, but I no longer live where this was.

  • Bijous Bijous on May 14, 2018

    Fix your gutters if they are allowing dripping water (or install if there aren't any there) and use ice tacks on the roof to prevent build up. Covering up your a/c permanently is a big no-no.

  • Catherine Deirdre Rodden Catherine Deirdre Rodden on May 14, 2018

    Would it be possible to build a wishing well type roof with the frame around your unit but instead of actual sides, use screening (like in windows and doors) that can be painted to look like wooden sides but still allow the air flow needed for the unit?

  • Harris S. Harris S. on May 15, 2018

    Make a cap for it. 2x4 frame and top it with plywood. That's all I ever use. It will keep out rain, snow, ice and leaves. We live in Wisconsin and have every kind of weather.

  • Laura Cooper Laura Cooper on May 15, 2018

    You really shouldn't roof your a/C. It won't work right. Get an a/c cover for winter and remove it in the spring.

  • William William on May 16, 2018

    The condensers are made to be out in the weather. No cover for the winter. Chris is correct. Brian Wilson is wrong. A sheet of plywood and something to hold it down just for the snow. A cover will hold moisture, trap dirt and the fins/ tubing will start to corrode. Repair the roof leak/gutters. Extend the roof line over the unit like an awning. Build a lean to roof at least three feet from the top of the unit.The roof slope will direct the hot air away from the unit.

  • Elaine Elaine on May 16, 2018

    Check with York’s minimum clearance. I’m also in the South, NC and ours are heat and air. But looking at the end cap on your gutter, it appears to be pulled out a bit from the gutter. Remove it, clean the gutter and end cap with some mineral spirits, replace and caulk. Also make sure your gutter is sloping away from ac unit and the downspout flows freely. I wouldn’t cover it with anything, that wouldn’t allow sufficient air flow but I have lots of family that live in western PA and several cover theirs. I’ve not heard of one being covered lasting longer than one that wasn’t.

  • EvaUnit EvaUnit on Aug 04, 2021

    I don't see any reason to do such a thing

    • Evalewisd Evalewisd on Aug 08, 2021

      Actually there is. If I were you, I would probably consult with someone with expertise at first. When I needed to replace my AC on the roof, I wasn’t supposed to do it without an expert because it might hurt my house in architectural terms. I don't see your case correctly, but before doing such construction, it is better to make sure that everything will remain stable. I recommend you to use the services of since they have the most affordable price on the market