How to add a coffered ceiling to your home

You can add this decorative treatment to your home with just moderate woodworking skills. By JEFF BRANCH.

Contents:

Introduction 1

Locate and mark the ceiling rafters 3

Layout the beams 4

Framing begins 6

Adding the second row blocking 9

Making the coffer boxes 10

Adding the third row framing 12

Adding moldings 17

Adding the joint trim 22

Variations to this plan 25

Completion 26

JBWW Jeff Branch Woodworks

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How to add a coffered ceiling to your home By JEFF BRANCH

Y ou might think that adding a coffered ceiling to your home would be hard to do, but it really isn’t. What it does take is some careful planning and a few simple tools. I found this project to be pretty

straight forward, repetitive (which means I got faster as the project progressed) and well within the means of someone with moderate woodworking skills. This article will take you through the process as I did it in my home. Keep in mind that my project was a painted coffered ceiling, which is a lot easier than stained coffers. If, for example, some of your crown molding does not fit exactly as it should, small cracks can be filled with caulk and then painted - problem fixed. With stained coffers, filler won’t stain the same color as wood, so problems like this will stand out. Also, with stained coffers, wood selection becomes important: what does the grain look like; any knots? In my project, I used wood with knots, but you can’t see them due to the paint. This article features drawings and photos to help you through the process, but I assume that your room is in the least, slightly different from mine. This means you will need to take the steps I used to lay out the beam

Tools needed for this job Having the right tools is everything in woodworking. Here is what I see as the minimum list of necessary tools for this job: Pneumatic nailer.

Remember that much of the work will be overhead and holding a board while trying to drive a nail with a hammer is impossible.

Screw gun. I used a lot

of screws in this project, so you will need a cordless drill to help with this.

Drill and Drive. This

tool combines and drill bit along with a screw driver and is very handy.

Table saw. You will have

to rip boards to width, cut them to length, add lap joints and more.

Powered miter saw.

There are a lot of miters in this project. The easiest way to cut them is with a powered miter saw.

Stud finder. This tool

will help you determine the location of your ceiling rafters.

Chalk line. Helpful to

draw the location of the ceiling rafters and your coffers.

Sander. I used a palm

sander and sandpaper on this project.

© 2011 Jeff Branch Continued on page 2

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Some considerations with this project

locations and adjust them to fit your room. One limitation of my project was our 8’ ceiling height. If you have 9’ or greater ceiling height, you can make your coffers deeper than mine (see page 26). You can simply take my overall process and add larger crown molding and adjust the height of some of the boards, to make this project better suit your room. Know that you may encounter situations that are unique to your home and not covered in this article. You will need to have a smooth, non-textured ceiling before you tackle this project. The material I used was the typical 1 x 6 paint grade pine available at the local home center. Regardless of the material you choose, be careful to select boards that are straight, flat and free of large, nasty knots. The big picture First, there are a number of ways a coffered ceiling can be constructed. When I began planning this project, I knew that this would be a site constructed job (meaning installed piece by piece in my living room) versus a project where large sections are made elsewhere and then moved to my living room for installation. Except for a couple of steps, this was a one man job, which makes working with large, pre-assembled components very difficult and even prone for errors. Speaking of errors, the design of this ceiling has making mistakes in mind. I have been woodworking for about 30 years and I make mistakes on every project. The illustrations in this article are based on a perfectly square room and a perfectly flat ceiling. In reality, this is never the case. My living room isn’t square and my ceiling had one significant (but not noticeable) hump in it. This can be a problem

when cutting angles and such; and can increase the possibility of mitered angles not fitting properly. I have designed this ceiling so that most of the joints are covered up by something. And as I said before, the fact that this project is painted means that small mistakes can be caulked. I poured through pages of many magazines before choosing this design—magazines like Architectural Digest and Traditional Home. I even did internet searches of different architectural styles to get ideas of what may look good in my home. You may want to do the same thing as you adapt this design to fit your own home. Prepare yourself Read over the steps of this project a few times before you start construction, especially the section on page four that discusses how to lay out the coffers in your home. The math can be a little tricky for anyone like me that is math challenged. It is important to first work out on paper how the coffered ceiling will work in your home taking time to properly adjust the location of beams to fit your room. Also, I recommend that you use a chalk line not only to identify the location of ceiling rafters but also to mark the outer edges of the first row framing. All these chalk lines can be confusing, but not so if you use one chalk color for the rafters and a different color for the beams. You can find colored chalk at your local hardware store. When using power tools, be sure you follow the recommended safety steps to ensure an injury free project. Now, let’s get started on the coffered ceiling.

Step 1: Locate and mark the ceiling rafters

3b. Using a stud finder, locate the rafters along each wall. Rafters are usually 2x10’s for example. It is help-ful to mark both sides of the 2x10’s. Rafters are normally spaced 16” on center.

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First a drawing of my living room

3a. Here is a sketch of my room. Because I completed this project several years ago without taking photos of the process, I am recreating it using Google’s SketchUp 3D drawing program. This powerful drawing tool will allow me to construct my coffered ceiling step-by-step.

3c. With the help of a friend, grab your chalk line and snap a line down the center of each rafter. This will be your visual indication of each rafter’s location.

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Step 2: Layout the beams

In my living room, I have three rows of five coffers (see the illustrations on page 6). The finished size of

each beam is 5” wide, not including the moldings. It is important to remember that the beams which

run around the perimeter of the room start out 4 1/4” wide and the interior beams start out 3 1/2” wide.

There will be additional pieces added to them to make them all 5” wide.

Now for a little math...

My room is 167” wide and 137” deep. To arrive at the spacing of the beams, for example on the width, I

took the 167 and subtracted 30 to get 137”. The 30 represents six rows of 5” beams. To find the width of

the interior boxes, take the 137 and divide by the number of coffers which in my case is 5 boxes. This

equates to roughly 27 3/32” (see this measurement in the illustration in 4a). Follow the same steps to

determine the dimension of the depth of each box.

Your room will not be the same dimensions as mine, so use the formula above to adjust the layout of the

beams in your home. For this reason, the dimensions shown in my illustrations are meant to help ex-

plain the construction process more so than to provide measurements for cutting components.

A cross section view

4a - This illustration is a cross section view of the coffer in the corner of the room. This means that the

beam on the left and the beam that runs left to right across the back are adjacent to a wall. The beam on

the right is an interior beam. This gives you a little better understanding of the construction. It is basi-

cally layers of boards that are boxed in with trim and molding. Because the interior beams are boxed in

on both sides, their layered boards are more narrow than those that run along the perimeter of the

room (the perimeter boards are boxed in on only one side).

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Laying out the beams continued

5a - The beams around the perimeter of the room (highlighted in yellow) are 4 1/4” wide.

5b - The interior beams (you guessed it, in yellow) are 3 1/2” wide.

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Step 3: Framing begins

6b - With your calculations, snap new chalk lines showing the outer edge of the first row of beams. You should have a grid something like that on page 5. We will first concentrate on the beams that run left to right across the room. In the illustration left, using a dado blade in my table saw, I have cut the needed lap joints. Their locations are taken from the chalk lines drawn on the ceiling.

6c - Remember that the boards which run around the perimeter of the room are 4 1/4” wide. The interior boards are 3 1/2” wide. The notch for the lap joints in the corners of the room are different than those of interior boards.

6a - Using the cross section view, note the beams for the coffered ceiling are built up from three layers of boards (highlighted in yellow, red and blue). The first step is to add the first (or yellow) row of framing. Adjust the calculations used on page 5 (see “Now for a little math...”) to compensate for the size of your room.

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Framing continues

7c - This illustration shows an example of a beam that runs front to back. The lap joints on the ends are 4 1/4” long and the two interior lap joints are 3 1/2” long. The depth of the lap joint is 3/8”

7b - Here I have installed the beam shown in step 6b along with the remaining beams that run across the length of the room. These beams are screwed into the rafters above. These four boards form the back bone of the project. All of the rest of the first row framing attach to these beams.

7a - In my home, I had a wall which was longer than the board I had purchased. Additional lengths of boards were joined at lap joints as shown to the left.

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Initial framing concludes

8c - Using the cross section drawing, it is time to start the second row of framing, indicated in red. This row is made up entirely of blocking.

8b - This illustration shows the remaining front to back beams installed.

8a - Here I have taken the beam shown in 7c and put it in place (indicated in blue). This beam is screwed into place at the lap joints.

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Step 3: Adding the second row blocking

9a - The second row blocking should be sized according to the width of the beams. There are three sizes as indicated in the illustration. I have color coded them for ease of identification.

9c - In this drawing, note the yellow, red and blue blocks: Yellow = 4 1/4” x 4 1/4” Red = 4 1/4” x 3 1/2” Blue = 3 1/2” x 3 1/2” Once these are added, the second row is complete.

9b - These blocks are located at each lap joint. In the illustration, I have added the first block in the corner of the room, attached with nails and glue.

Step 4: Making the coffer boxes

10c - After cutting the board to length, the second step is to cut it to the proper height—in my case, 2 1/4”. The third step is to cut a notch 3/4” deep and 5/8” wide.

10b - The inner coffer boards are each fabricated in four steps. The first step is cutting the board to length. The length is the same as the distance between the first row beams, in my case, 40 1/2”.

10a - We’re making progress. It is time to attach the interior coffer boards, indicated in green.

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Making the coffer boxes, continued

11c - Here, I have three boards installed. Repeat this process until you have each coffer boxed in.

11b - I attach the board to the first row beam with nails.

11a - The last step is to cut 45 degree angles on each end as shown. The side that will be visible should be sanded prior to installation.

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Step 5: Adding the third row framing

12c. We will be making some specific angled cuts for the third row boards. Each second row block will provide a nailing point for the third row. I have drawn a diagonal line on the block on the left to indicate how the third row boards will intersect at the corners. The block on the right will have three boards which intersect as indicated with the inverted “Y”.

12b - Using the cross section view, the third row is shown in blue and fits into the notch on the interior coffer boards.

12a - The coffered ceiling is starting to take shape. We have most of the framing in place and the interior coffer boxes completed. It is time to finish the beams with the third row framing.

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Third row framing continues

13c - Go ahead and cut boards with this same profile for the three remaining corners. Install them by nailing into the blocking.

13b - Here is the board installed. I have colored it blue to make it more visible. This board is nailed into the blocking.

13a - Based on the lines drawn in the blocking in 12c, here is the board that will need to be cut. It has a 45 degree cut on the left end and a 45 degree notch on the right end. The board is 4 7/8” wide. Also, the visible side of these and subsequent boards for the third row, should be sanded prior to installation.

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Third row framing continues

14c - Repeat this step for the two other perimeter beams, as shown.

14b - Install this board as shown. Repeat this step for the opposite wall. This step completes these beams.

14a - Let’s start connecting the corners. Cut boards that have a 45 degree notch on each end as shown.

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Third row framing continues

15c - Here, I have installed all of the boards that move towards the center of the ceiling. Note how the boards meet up where beams intersect.

15b - Here is a close-up of the board needed for this step.

15a - It’s time to move on to the interior beam components. Begin this process by making a board that has mitered corners which form a point. Do this for each end.

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Completing the third row framing

16c - A milestone in this project: all the beams are completed. Now the really fun part begins—adding the molding.

16b - In this illustration, the final boards for the front to back beams are installed.

16a - In this step, I have completed the beams that run left to right across the room.

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Step 6: Adding moldings

17c - The crown molding, shown in brown in 17a, is very small, measuring 1 1/4” tall by 1” deep. I also purchased it at Lowes. If you want to make your coffers deeper, simply buy larger crown molding. You may even want to consider a two or three part molding profile. See page 25 for more details.

17b - I purchased the moldings at Lowes. The flat molding shown in deep red in 17a is called “shingle mould” and measures 1 5/8” wide by 11/16” deep.

17a - Moldings make a big impact on a room. This two part molding is no different. You can see the two profiles in the illustration indicated by different colors.

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Adding moldings

18c - Measure the distance between the intersecting lines and make your 45 degree cuts on the shingle mould.

18b - Draw lines 2 1/2” in from the edge of each beam as shown.

18a - Using the cross section view, the front edge of the shingle mould should be positioned 2 1/2” in from the beams. Note that the back of the shingle mould does not touch the beam.

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Adding moldings

19c - Complete the application of the shingle mould as shown. Repeat these steps for the remaining coffers.

19b - When applying this to ceiling sheetrock, use an adhesive like liquid nails or adhesive caulk. Use your brad nailer to keep the molding in place while the adhesive dries.

19a - With the measurement from 18c, make the necessary 45 degree cuts on each end of the shingle mould. Each piece of molding should be sanded as needed.

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Adding moldings

20c - In this illustration, the crown has been cut to length and 45 degree miters have been made. In my installation, the length is 39” which fits the long side of the coffers.

20b - The crown molding shown highlighted in brown is attached to the shingle mold and the beam with brads from your pneumatic nailer.

20a - Here we see all of the shingle mould installed. Next, we need to add the crown molding.

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Adding moldings

21c - This process is repeated so that the crown molding surrounds the inside of the coffer. Then continue adding crown molding to all of the coffers on your ceiling.

21b - In my installation, the crown is 3/8” above the bottom of the beam.

21a - Here I have taken the crown molding from 20c and installed it with my nailer. See the close-up in 21b.

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Step 7: Adding the joint trim

22c - I have indicated in purple, the trim necessary for this step. The long slender strips are 1/8” thick hardboard and there is a 1/4” thick plywood piece that caps the joints where the beams intersect.

22b - In this illustration, notice how I added trim to cover all of the joints. This is a practical step, since some of boards can warp slightly causing joints fit improperly. This step is also decorative. Some of the photos I ran across while researching the design of my coffered ceiling had this same kind of trim which causes additional shadow lines and visual interest.

22a - Congratulations. All of the molding has been installed. When I did this step, it went well, but with 15 coffers, I cut 120 pieces of molding! Now on to the final step—adding what I call joint trim.

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Adding the joint trim

23c - Now that all the trim blocks are in place, fill in with the thin hardboard strips. Measure the distance between the trim blocks—in my case 39”.

23b - Here, all of the trim blocks have been installed.

23a - These little blocks are 1/4” thick and 5” square. Attach them at each beam junction with your nailer.

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Adding the joint trim

24c - Complete this job by filling any small cracks with paintable caulk, set nail heads below the wood surface and fill the holes with wood putty. Sand as needed. Apply a good quality primer and then paint the ceiling a color of your choice.

24b - Strips are used on each edge of interior beams.

24a - These 1/8” hardboard strips are 1/4” wide. On the beams that run around the perimeter of the room, install a single strip on the inner edge as shown.

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Variations to this plan

25a - If you have 9’ or higher ceiling height, you should alter my design to take advantage of greater space. In this cross section illustration, I have drawn an example of a multi-piece crown molding. To accommodate the size of the larger crown, you will need to add a board that runs the perimeter of the room, attached to the wall (indicated in light blue). You will also need to lengthen the inner coffer board accordingly.

25b - A taller inner coffer board means that you will need to alter the location of the second row blocking. Instead of attaching this block to the first row framing, you will simply attach it to the third row boards where these boards meet each other. Center the blocking at each board point and align the back of the block with the beginning of the 45 degree notch.

25c - Installing these together gives you a nailing point for subsequent boards at each intersection.

Completion

© 2011 Jeff Branch. Unauthorized duplication or sharing of this electronic file is prohibited. For more tips on woodworking projects visit my website: http://jeffbranch.wordpress.com

I hope you enjoyed this project. After writing this e-book, I remembered how fabricating all the boards for the third row

could get a little tedious, as well as cutting and attaching all of the molding, but as one person said, “It looks AMAZING.” I don’t know about that, but I am very pleased with the effect in our living room (it is hard to believe from the photo above that the depth of the coffers is only 2 1/2”). I later added the fluted columns to both doorways of this room to complete the look I was trying to achieve.

If you have any questions about this process or even suggestions on ways to improve this woodworking plan, feel free to drop me a note via email—the address is found at my blog (link below).

JBWW Jeff Branch Woodworks