How Important is a Level Door Sill?


it’s not that big of a deal… is it?

How Important is a Level Door Sill?


Let’s take a look…

This is a question that most people don’t think about before beginning a door installation, but it might be the most important step to take. Installing a door with a level door sill is like building a house on a level foundation, you have to start right to end right.

picture-correct-door-sill-vs-an-incorrect-door-sill

As you can see in the picture above, if you don’t start with a level sill, it’s practically impossible to end up with a good result to your door installation. The sill is the door’s foundation, if it is out of level; the problems compound over the height of the door and become much more difficult to troubleshoot.

Now that we know we need a level sill, it’s easy right?  Well in the real world, you’ll find most construction sites don’t offer a perfectly level sill area in the rough framing.  In fact, it’s very uncommon to find a perfect RO (rough opening) with a perfect sill. So what do you do?  You fix it!

Take the time

It’s important to use a straight edge level long enough to run the entire length of the door sill to make sure that the entire span is level and without dips or rises. A dip or a rise in the sill must be fixed before beginning the door installation.

One of the best methods we’ve come across to fix a dip or a rise in the door sill is to use strips of Ice and Water shield (found on most jobsites as a roofing underlayment) or asphalt shingles to build up the rough framing in order to create a level door sill.  Depending on the thickness you need, the strips are easy to cut and stay nicely in place where you need them during the door’s installation and afterwards. 

  By taking the time to complete this small step, you will find that many common door installation problems disappear when you start with a level sill!


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JENTRA door levels

One thing has stood out clearly to us in our combined 15 years of experience in both the sales and installation of residential/commercial doors…. the lack of accurate door installation happening in the field. This installation process has been virtually the same since pre-hanging started in the 1960’s and yet it’s not uncommon to find a poorly installed door on most jobsites. It’s time to take a new look at this.

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CHEATAH door level

CHEATAH door level

The CHEATAH™ door level kit makes installing a door simple and quick. Attach the CHEATAH directly to the top and sides of the door. The four precise levels work together to allow easy, accurate positioning of the door. Once level, the built-in shim guides let you correctly shim the jamb. The CHEATAH works on all types of doors with perfect results each time. Our door level kit is extremely durable and carries our 100 Guarantee™. Save time and money installing doors right the first time, every time. The JENTRA CHEATAH door level puts advanced speed and precision capability into the hands of all skill levels during installation, from DIYers to skilled artisans. This results in improved installation and function of doors, resulting in fewer warranty callbacks. Therefore, stakeholders of the door level include all steps in the industry: door manufacturers, distributors, contractors, and building owners.

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