Important points

• There is no more important tip to installing Velux windows than to follow the flashing instructions for each window. There are similarities from one type to another, but there are also unique functions to each flashing kit. With that in mind, when you are purchasing a Velux window, do not forget that you must purchase the flashing kit that accompanies your window.
  If you purchase the incorrect kit, you may find yourself trying to fit parts that do not match your window. This ultimately result in a leak, so take the time to double-check that your flashing kit matches the window. When installed properly, the windows will not leak.
  
  

Cautions

• You may be advised that these windows can be installed by yourself. Although it is true and many professional install them alone, it is much safer and easier to have an assistant. Velux windows are not heavy, but they are substantially built, and handling them alone on a roof can be dangerous. Have someone help you safely put the window and flashing kit in place. The last thing you want is to fall off the roof while trying to hold on to several parts. In addition, the windows are expensive, so you don't want to damage your window while putting it in place.
  
  

Success

• Each window comes with detailed instructions. Make sure to read and understand the procedures outlined in the instructions. If this is your first installation, conduct a dry run walk-through on the ground. Installing the window itself is the easy part. The most important stage is the flashing installation.
  Do not nail through the flashing into the roof material -- only nail the flashing into the skylight itself with the nails that are provided with the kit. You may be tempted to nail the flashing to the roof, thinking that by doing so you are better securing the window. Instead, what you will be doing is providing another access point for a leak.
  Velux windows and flashing kits provide you with everything you will need to ensure a leak-proof window. Take your time. It may seem like a task you would rather pay a professional to do, but even professionals have to read the instructions.
  You can do it.