Installing trim just got do-able for beginners! Crown molding, chair rail, window and door casing, and shadow box trim — Jenny did it all as a complete beginner and she’s sharing what she learned so you can do it, too!
Installing Trim: A Beginner’s Guide
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A quick Remodelaholic note: Before your pick up the perfect trim and start cutting, be sure to practice on an inexpensive piece of molding (or scrap) until you have an understanding of how the angles will work. Jenny recommends some resources below, so read up, watch some videos, and practice, practice, practice!
When I first opened the instruction manual for a compound miter saw, all I saw were warnings about the appendages one could lose if the saw was used improperly. I was so frightened and so intimidated that three months went by before I tried to use the saw again.
Unfortunately, power tool manuals are written for people who already know how to use the tools, not for DIY newbies like me. A manual won’t tell you the basics like how to release the blade lock. (It took me nearly an hour just to figure out how to do that!).
1. Research How to Install Trim
2. Create a Work Space
3. Acquire Tools and Supplies
- A Compound miter saw (a sliding compound miter saw is ideal, but a 12″ regular one will work just fine). I used a Dewalt.
- 18-gauge brad nailer (for shadow boxes) and 16-gauge finish nailer (for crown molding) and an air compressor. I bought them as a 3-tool Combo Kit and have been very happy with it.
- Brad nails and finish nails
- A ShopVac to clean up all the saw dust you’re going to generate. I found an 8-gallon wet/dry ShopVac at Costco.
- A 24″ level and 9″ torpedo level
- Measuring tape
- Multi-purpose protractor
- Wood Filler
- Sanding Sponge
- Caulk. After trying several, this DAP caulk is my favorite.
- Caulk Gun
- A crown molding chart that tells you what degrees to set your saw for cutting angles. I used the extensive chart available in the book Crown Molding & Trim: Install it Like a Pro, but I learned all the practical knowledge I needed for cutting crown molding on pp. 128-137 of the book Trim Complete, which has excellent pictures to accompany the clear instructions.
- A bag of pre-cut trim scraps labeled with their angles. I cut several different pieces of scrap trim (the ogee molding for shadow boxes and the chair rail molding) in increments by degree to use for figuring out angles. I preferred to use a protractor to measure angles for crown molding, but found that for chair rail and shadow boxes, it was faster to use my scrap trim samples. For example, I cut pieces of scrap chair rail at 15-degrees, 18-degrees, 20-degrees, 25-degrees, etc. Then, when I came across a corner where two walls meet, I’d hold up two pieces of my scrap trim (cut at different angles) until I found the 2 angles that came together for the best fit. That’s how I knew what angles to cut each piece of trim.
- The BuildCalc app and This Is Carpentry’s tutorial on how to use it. This app saved me all kinds of headaches when designing the shadow boxes. I simply measured the wall and figured out how many shadow boxes I wanted there to be and then entered the numbers into the app to find out the spacing.
- Trim Wood
- Ladder or tall step stool
4. Plan Out Every Detail
To come up with a design for my trim work, I browsed sites like Houzz and Pinterest for ideas.
(Remodelaholic note: We also have a post here with lots of wainscoting styles.)
Once I decided what I wanted to do, I measured all the walls and calculated how much wood I would need.
Word to the wise, give yourself plenty of overage. You won’t be able to use the entirety of every piece of trim and you will certainly make mistakes.
If you’ll be undertaking a large, multi-room project like I did, I recommend doing a small room first to get a feel for how much wood you’ll really need (it will be more than the exact measurements) and for how much time it takes.
The lumber yard also delivered (for a fee), which, given the size of my project, was enormously helpful. Store the wood indoors where you’ll be installing it and give it 3 or 4 days at room temperature before using it.
5. Draw on your walls.
I drew every last piece of trim on my wall before making any cuts or nailing anything in place. It’s a lot easier to make adjustments with pencil drawings than with wood.
I measured from the floor to the top of my chair rail molding, making a mark on the wall about every 18 inches. I then used my level to draw a straight horizontal line connecting all the marks so I would know exactly where to place the trim.
Same thing for shadow boxes. I measured then marked where they would go and used my level to draw straight lines connecting all the markings. Also, when I drew the lines, I measured them right then and wrote the measurements on the walls (I double-checked the measurements before cutting any wood.)
I found that if I put a nail at each corner (not too close to the edge, though, or you’ll risk splitting the wood) and about every 8 to 10 inches, that was plenty.
- Nail holes. Use wood filler, not caulk to fill your nail holes. Use a light hand with the wood filler as you’ll have to sand whatever dries on your trim. I suggest using a lightly-damp rag to wipe over newly-filled nail holes to minimize sanding later on.
- Sanding. Sanding sponges are great for carved moldings and most trim work with minimal wood filler to be sanded.
- Caulk. It will feel like you’ve caulked miles of seams, but do it! It will give you that seamless look where the wood appears to just grow out of the wall. As mentioned above, this is my favorite caulk (I tried several different kinds over the course of my project). Buy by the case to save money. You’ll use a ton of the stuff!
Get tips for caulking like a pro here.
I put up hundreds of feet of trim: chair rail, crown molding, and dozens of shadow boxes.
I did every last bit of the job entirely by myself. I had a general contractor come by to take a look at all of the trim work I did. He told me that if I’d hired him to do the work, he would have charged me at least $10,000. The wood for my entire project cost me about $1,500.
Paint colors are Benjamin Moore White Dove (white) and Restoration Hardware Silver Sage (light blue).
With Sherwin Williams Naval for the dark navy blue
I hired someone to paint it all after I finished installing trim.
Thank you so much for sharing your tips and your gorgeous home with us, Jenny!
Also check out:
- Jenny’s Kitchen Transformation
- 25+ Wainscoting Styles
- Tips for Caulking
- How to Install Board and Batten
- Installing Custom Wood Pre-Hung Doors | Basement Remodel
Please pin this for future reference!
Originally published 07.07.2015 // Updated 04.14.2021