Premium sill

Premium Window Sills

Sill–Rite Premium Sills provide an attractive accent to any home while offering unsurpassed protection. Available in a classic or contemporary style, Sill–Rite window sills are waterproof and won’t rot, peel, or yellow.

The finished ends are fabricated and have a fine seam, similar to traditional fine-crafted wood sills.

Sill–Rite Premium Sills are available in sizes to fit standard window openings. Each sill is completely fabricated with a striking profile on not only the front, but both ends—unlike sills that are butt cut.

“Your product is awesome. It dramatically changed my manufactured home’s appearance and it now looks better than my last home, which was custom built.” Kathie
Calhan, CO


Classic sill

Sill-Rite’s Classic profile provides an attractive traditional appearance.

Streamline sill

For a contemporary look, choose Sill-Rite’s Streamline profile.

Window Width Sill Length
11"-14" 17"
17"-20" 23"
23"-26" 29"
29"-32" 35"
35"-38" 41"
41"-44" 47"
47"-50" 53"
53"-56" 59"
59"-62" 65"
65"-68" 71"
71"-74" 77"
77"-80" 83"
83"-86" 89"
89"-92" 95"
95"-98" 101"
Custom lengths available


Premium sills are individually prefabricated to fit typical window openings.

Sill Length

Measure the width of the inside jamb to jamb of the window opening. The standard lengths of Sill–Rite sills are meant to fit standard window widths. The sill should extend 1½ to 3 inches beyond the jambs on each side of the window opening.

On the chart to the right, look in the Window Width column to find the bracket in which the width of your window opening fits. The Sill Length column indicates the recommended sill length. Check the recommended sill length to make sure the sill will fit properly for your window opening.

For example, if your opening measures 35½ inches, the corresponding sill length is 41 inches. This length sill will extend 2¾ inches beyond the jambs on each side.

If your window width is not listed, a custom length sill can be ordered. You determine how much the sill extends on either side of the opening (there is no “standard” amount of extension; it’s simply a matter of taste). You can also choose the next largest sill if you like the extra extension.

NOTE: If you have window casing around your opening, make sure the length of the sill will extend past the trimwork.

Sill Depths

Sill Depth

Premium sills are available seven depths — 2in, 3in, 4in, 5in, 6in, 7in, and 8in.

Extended Depths

Extension Kit

Sills deeper than 8in are available with an extension kit. These extended depths include:

Extended Depths: 9in, 10in, 11in

Installation Instructions

Installation Video

VideoClick here to view a video demonstrating how to install a Premium sill.

Installation Sheets

Basic Installation — Step-by-step instructions for most applications.

Installation for Multiple Windows — If you have two or more windows close together, it may be best to install one long sill across a set of windows. These step-by-step instructions show you how.

Installation in Bull Nose Drywall —If you have bull nose corners in your sill area, there are a few handy tips for cutting the sill to fit perfectly.

Extension Kit Instructions - Sills deeper than 8 inches use an Extension Kit. These are additional instructions for installing Extension Kits.

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