[Note: This entry was actually written in May 2013. I changed the posting date to keep my blog entries in chronological order]

by George Taniwaki

Before the remodel, the kitchen had two windows on the left that were single horizontal sliders while the right window was an aluminum garden window. All three windows were trimmed with 2″ wide MDF casing with mitered corners (Fig 1a).

As part of the kitchen remodel, we replaced the three windows with fixed (nonopening) windows and trimmed them with traditional 3-1/2″ wide solid wood Craftsman-style casing (Fig 1b). Note how the casing above the windows fits flush to the soffit.



Figures 1a and 1b. Kitchen windows before remodel (above) and after (below)

Finish carpentry is usually straightforward work and often doesn’t even require a tape rule. However, this project is bit more complex, but manageable for an advanced do-it-yourself homeowner.

Install the replacement windows

To unify the kitchen design, the three replacement windows will all be the same size and style. To determine the correct size, measure the dimensions of the three rough openings for the existing windows. The width of the replacement windows should be about 3/8″ narrower than the narrowest rough opening. Similarly, the height of the replacement windows should be about 3/8″ shorter than the shortest rough opening.

Once the windows arrive, inspect for damage. When installing them, note that the rough-openings are not likely to be identical in size, nor will they be level, plumb, and square. By using shims and a level, install the new windows and ensure they are level and plumb. When mounting the windows, make sure they are square relative to the foundation of the house, not to the rough openings. Follow the directions that come with the windows.

The exterior opening is finished with brick molding to match the existing siding (Fig 11).

Even after the careful installation, I noticed a few problems with the new windows which may typically occur.

  1. The windows are not centered within the rough openings, leaving several large gaps (over 1/2″) between the windows and the framing
  2. The windows are not all at the same height. The middle window is about 1/4″ higher than the left and right windows
  3. The windows are too tall and don’t have room at the top for the wide casing to fit under the soffit
  4. The new windows are vinyl-clad and won’t match the color or texture of the solid wood casing

The casing design

The basic design for the casing for the windows was specified by Soderstrom Architects to be 3/4″ x 3-1/2″ S4S oak stock with a 3/4″ bullnose accent on the crown (Figs 2a and 2b). Since all the doors in the remodel are fir and hemlock, I decided to make the window casing from hemlock rather than oak. Also, 3/4″ bullnose stock is hard to find, so rather than custom mill it, I went with the more commonly available 1/2″ (0.46″ x 1.20″ actual) bullnose (Fig 3).


Figures 2a and 2b. Front view of entire window (left) and detail of upper left corner front view and cross-section view (right). Drawings courtesy of Soderstrom Architects


Figure 3. Front, top, and side views of top casing when using 1/2″ bullnose

I modified this design to solve the four issues identified earlier. First, I will add shims as needed to fill any gaps the between the framing of the rough opening and the casing (solving problem 1). I will also add wide shims to the top of all three windows behind the casing to support it (problem 3).

Second, I will use hemlock to clad the window to completely hide the vinyl (problem 4). Each piece of the hemlock casing will be a custom sized to ensure the bottoms of all three windows are the same height from the countertop (problem 2) and the tops of all three windows perfectly fit under the soffit (problem 3). Each of the four sides of each window will be covered by four pieces of hemlock casing. The top side will receive an additional bullnose accent.

The front view, cross-section view through the side, and cross-section through the top are shown in Figures 4a to 4c. The four pieces of hemlock casing are numbered 1 through 4 and have red lines and gray fill. (The bullnose accent is omitted for clarity.) The shims have red lines with white fill. The double pane glass is shown in with blue lines. The location of the vinyl cladding or rough opening is shown with dashed green lines.



Figures 4a to 4c. Front views and cross-section views of casing design

Make the casing

Make accurate measurements in the field of all the dimensions of the windows and the distance from the framing of the rough openings to the windows (Fig 4). There are 3 measurements to make for each piece (length, width, thickness), up to 5 pieces on each side of the window, 4 sides on each window, and 3 windows, for a total of 180 measurements. Use an Excel spreadsheet to keep track of all of them. Using Excel also allows you to sort the pieces by size so that you can develop a cut list.

In all of the descriptions below, when cutting the pieces to length, cut them about 1/8″ longer than required and trim to exact length in field (using a block plane) to ensure a tight fit in the corners.

Shims – Start with 2″x4″x8′ nominal (1.5″x3.5″x96″ actual) lumber. Cut the lumber to length. (It’s okay to make the shims a little short since they will not be visible.) Rip it to the required width and thickness. The top shim is about 2″ thick, so it will require gluing up two shims (one 1.5″ thick and another 0.5″ thick).

With the shims in place, the sizes of pieces 3 and 4 will be nearly identical for all 3 windows.

Piece 1 – Start with 1″x4″x8′ nominal (0.72″x3.5″x96″ actual) S4S hemlock. Plane it 0.60″ thickness. Round over one edge. There are various widths, ranging from 0.6″ to 2.7″ to fit around the window (there should be about a 1/8″ reveal between Pieces 1 and 2). Cut stock into pieces long enough for each width. Rip the stock to the various widths. Cut to 1/8” over final length.

As can be seen in Figure 4b above, the back side of piece 1 fits against the glass pane of the window, meaning it is visible from the outside. Finish the back side with 3 coats of gloss enamel paint to match the color of the exterior trim. Finish the two sides visible from the inside of the house with stain and 3 coats of varnish (Fig 6).

Piece 2 – Start with 1″x3″x8′ nominal (0.72″x2.5″x96″ actual) S4S hemlock. Plane it 0.60″ thickness. Round over one edge. There are various widths, ranging from 0.8″ to 2.5″. Rip the stock to the various widths. Cut to 1/8” over final length. Finish the two visible sides with stain and 3 coats of varnish.

Piece 3 – Start with 1″x3″x8′ nominal (0.72″x2.5″x96″ actual) S4S hemlock. Rip it to 2.2″ wide. Round over one edge. Cut to 1/8” over final length. Finish the two visible sides with stain and 3 coats of varnish.

Piece 4 – Start with 1″x4″x8′ nominal (0.75″x3.5″x96″ actual) S4S hemlock. These are the most visible pieces, so ensure the stock has good grain pattern and is straight with no bow, twist, or cup (Fig 7). Round over two edges. Cut to 1/8” over final length (there should be about a 1/4″ reveal between pieces 3 and 4.).

The top piece of casing has a 1/2″ bullnose accent that consists of three pieces as shown in Figure 3. Cut the bullnose stock to 0.9″ longer than piece 4 and bevel at 45°. Cut two triangular shaped return pieces for each end. Glue the bullnose pieces to the top piece of casing and tack in place with 1″ 18ga. brads. Be careful not to split the wood when nailing the small return pieces.

For all sections of pieces 4, finish all the visible sides with stain and 3 coats of varnish (Fig 8).


Figures 5 and 6. Accurately measuring the window dimensions; completed piece 1 showing stain and varnish on front and paint on back


Figures 7 and 8. For piece 4, avoid twisted or cupped pieces of wood like the one on the far left; staining, varnishing, and painting of pieces in progress

Install the casing

Dry fit the shims, then screw them in place. Do not use a framing nail gun since an incorrectly placed nail could damage a window (Fig 9).

Dry fit pieces 1 and 2 around the windows. The pieces should fit snug so they stay in place without glue, but not so tight that changes in humidity could damage the frame or break the glass. Once all the pieces fit, remove them and apply clear silicon caulk to the painted side of piece 1 and spread it smoothly over the entire surface. Stick the pieces to the glass. You may need to use a wedge to keep the pieces from sliding around (Fig 10). Go outside the house to confirm a glue line is not visible (Fig 11).

Apply clear silicone caulk on piece 2 and attach them in place.

Dry fit piece 3 and install using wood glue and tack in place with  1-1/4″ 18ga. brads nailed into the framing (Fig 12).

Piece 4 is installed using 1-3/4″ 16ga. brads nailed into the framing. Fill the nail holes with putty. Finish the repairs with stain and one coat of varnish.You are done (Fig 13).



Figures 9 to 12. The shims are screwed in; piece 1 held in place using a scrap of wood and a wedge until the clear silicone caulk dries; checking the exterior to ensure the caulk is evenly spread on the glass; piece 3 nailed to the framing


Figure 13. The completed left window showing top casing fitting exactly under the soffit, please ignore the construction debris outside

Overall, the windows look nice from the inside. From the outside, you don’t notice the wide white band around the windows caused by piece 1. It probably would have been easier, and perhaps cheaper to buy windows with fir or hemlock frames in the first place rather than buy vinyl windows and cover them with wood. But it’s all a learning experience.

For more ideas on home remodeling projects see the Home Remodeling Guide.

All drawings and photographs by George Taniwaki unless otherwise indicated


To learn how the image in Figure 13 was made, see this May 2013 blog post.