The sill on the interior window does not need a slope as long as the exterior window sill is slanted downwards. That’s because when the exterior window sill is sloped the water does not collect on the sill rather falls downwards due to which no water enters the interior side of window. Hence, it is best to keep the interior window sill leveled with the floor.
Other benefits of a leveled window sill
Design symmetry
A level window sill looks symmetrical with other straight elements of window trim. For example, jambs, casing etc. This makes the window look great on the wall. Whereas if the sill is sloped then the parts of window frame that are close to sill looks odd. For example an arpon that is installed directly under the sill is sticked flat with the wall. Now a sloped sill above the aron simply does not look as symmetrical as a leveled sill would.
Provides a flat surface for placing decorative items
Decorative items that can be placed on the window sill like flower pots, small artifacts, or soft toys need a flat surface to be held firmly on the sill. Having a sloping sill can make these decor items to slip.
Easier to install
A sloped sill needs to be precisely made for an individual window while carefully considering all the angles and length from window casing. A leveled sill on the other hand is much easier to install as the only thing to make sure while installing it is to keep it leveled with floor.
What to do if interior window sills are sloped?
On inside windows, a slope of 14 degrees or less is hardly noticeable. It is when the slope on the window sill is greater than 20 degrees, any one of the two methods below can be used to make the overall window look better while covering the sill.
Install a pet seat near the sill
My friend like cats and if you also have a cat then installing a wall-mounted seat for the pet is a clever trick to cover the slope on the sill. These seats are designed such that the seat itself remains flat i.e parallel with the sill whereas the bottom legs of the seat are joined with the wall providing a strong and firm base to handle the weight of the pet easily.
Place a table of sofa near the sill
Many people prefer having their working desk near the window. There are several studies that has shown the importance of natural lighting in the workplace.
Having a desk near the window therefore not only provides plenty of natural light but also helps to cover the steep slope of the sill.
A sofa is also a good piece of furniture that can be placed near the window to cover up the sloped sill.
What size should the interior window sill be?
Ideally, the sill on the inside window should extend about an inch out from the casing from both front and sidewards.
Avoid making the sills pop out too much from the casing as it takes a lot of around the window such that placing any furniture near it becomes difficult.
Also if there is no apron to be installed on the window then the window sill can be kept flush with the casing i.e without an apron the window sill should be the same size as the casing.
Even if the window is of big size i.e around 60″ in length and 48″ in width such that the window seat can be placed below the window then also the size of sill should only be such that it extends out just about 1 inch.
What color should interior window sill be?
Interior designers prefers to keep the color of the same as the rest of the casing around the window.
The color of the casing and the window frame itself though do not need to be the same.
If the window frame is brown in color then the casing on the frame should be either brown or white color. If the casing is brown then the sill on the window should also be brown color and similarly, if the casing is white, the same color should be used for the sill as well.
Using same color for the casing and the sill makes the window frame and casing look like one complete unit in which both complement each other’s look.
Should all the windows inside have a sill?
No, it is not important for all the windows present inside the house to have a sill.
If there are multiple windows in a single room and if one of the window have a sill then all the other windows should also have a sill. However, windows with seats are exception.
In many modern bedrooms there are window seats. In such a window, a sill is not required as it is barely visible due to the seats underneath. In such a bedroom if there are other small size windows present then those windows can have sills irrespective of the window with seats.
For large size windows 60″ and above, having a sill is not important. Casing with sill around window looks good only over small to medium size windows.
If all the windows in the living room have proper casing around them with sills then the windows in bedroom can be left without sill as these two places are never at juxtaposition with one another so does the windows.
Whether to keep under window is ultimately a personal choice. Generally speaking, different re ooms have different architecture and the casing on the window should match with the architecture of that particular area.
