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.
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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