DIY Window Trim Molding – Easy How To Without Miter Cuts
Learn how to add chunky window trim pieces the easy way without any complicated miter cuts or special equipment to make smaller windows look bigger.
Not all of us are blessed with old charming homes with tons of architectural character. Our builder grade house is as bare bones as it gets. But we’ve learned one of the best ways to add character to a new home is to add a window frame to basic new windows.
In this DIY tutorial, we’ll walk you through the simple way to do your own trim project so your own windows exude the feeling of old house charm in every room.
This certainly isn’t one of those gorgeously creative DIY posts, but this little project is by far one of my favorites for adding some oomph to a space.
If you’re a home improvement beginner, you can do these easy DIY window casings with just simple straight cuts and no power tools at all. (Though power tools will speed up the process, if you’re willing to try.)
My favorite thing to DIY in our very plain new construction house is adding architectural interest, and since we’ve already done similar trim around our master bathroom‘s modern windows, I find myself drawn to the idea of chunky window molding throughout the rest of our house for a cohesive look.
You can find all kinds of versions of this similar trim all over the internet, but this is our very simple take on interior window trim without the high cost.
DIY Ideas to Add Character to Your Home
- 8 DIY-able Wall Molding Ideas to Add Character to Your Home
- How to Quickly Beef Up Crown Molding and Baseboards
- The Best Paint Colors for Gray Trim
Olivia’s bedroom window before was uh… lack luster. Blah. Boooooriiiiiing.
I mean, what’s a bedroom with a glamorous chandelier without some pretty window trim to go with it? That’s like wearing stilettos with your jogging shorts. Joan Rivers would have never forgiven us, bless her soul.
DIY Window Trim – The Easy Way Without Miter Cuts
Supplies
- 1×2 piece of wood (length depending on your window’s overall length and width)
- 2 1×4 boards
- 1×6 board
- Brad nails
- Wood screws
- Hammer (If you want to get the job done way faster, this cordless brad nailer rocks.)
- Paintable caulk
- Wood filler (for wood knots and nail holes)
- Primer (always prime raw wood before painting)
- Paint (I used a sample size of Valspar Du Jour and it was just enough.)
- Jigsaw (of whatever type of saw you prefer; a hand saw can work if you don’t own power tools)
- Nail setter
- Fine grit sandpaper
- Pry bar and utility knife (if you plan to remove existing trim to replace it with this method instead)
Different styles of molding can work for this method, but we used plain pine lumber to get clean lines in the finished look. You can use MDF board or other wood varieties.
For exterior application around an exterior window, you will need to use preservative-treated wood trim or composite materials to prevent moisture issues on the exterior of your home.
Steps
Here’s the game plan. A visual is probably easier for this one.
If you are replacing existing window trim, use a utility knife first thing to score the old caulk along the inside edge and outside edge of the side casings, head casing, and window sill board. Then, remove the old trim from the wall with a pry bar.
Step 1 – Make the Window Sill
1. We started on the window sill first. Cut your 1×6 to the width of the window plus 10 inches to leave an excess of 5 inches on each side.
2. Once we had the width of our 1×6 cut, we held it up against the bottom of the window to mark where to cut out the corners to fit into the window base.
3. Once everything looked good, we used the brad nails to attach it with a nail gun.
Step 2 – Add Window Trim Sides
4. For the sides of the trim, we held our 1x4s up on each side of the window to mark where to cut the length.
(Measuring is overrated in our house for some projects. If we can get away with lining up wood pieces, marking, and cutting, we do. It’s easier and just as accurate as going the extra step with a measuring tape.)
Step 3 – Assemble the Header
5. Once the sides of the trim were up, Robert got to work on the header by cutting the remainder of the 1×6 the same length as the window sill. He cut the 1×2 in two pieces using the same length as the 1×6.
6. I didn’t get a shot of him using wood screws to secure the 1x2s to the top and bottom of the 1×6, but you can get a good idea of it from the pictures. (Sometimes I’m just in awe of his mad skills and wonder to myself how I ever got so lucky for marrying such a handy guy and forget to pick up my camera…oops.)
7. He used brad nails again to attach the header to the top of the window and made sure to secure them into studs in the wall.
Step 4 – Add the Apron
8. He added a length of 1×4 under the window sill too (called the apron).
9. Caulk any gaps and wood fill knots. You can get a better idea of how the 1x2s are attached to the 1×6 from this angle. See that not so pretty gap between the wood and the wall? Caulk is your best friend.
Just so you know, I posed with my caulk gun doing an oh-so-awkward Charlie’s Angels pose and somehow it mysteriously disappeared from my memory card.
Good thing my caulking is better than my modeling.
Step 5 – Set Nails, Wood Fill, Sand, and Caulk
10. I went back over the brad nails with a nail setter one more time to make sure none were sticking out too.
11. I gave the nail holes a fill-in with some wood filler, let dry, then sanded.
Step 6 – Prime and Paint
12. Prime one coat on the raw wood so it will take paint more evenly and the wood knots won’t bleed through.
13. Paint 1-2 coats in the color of your choice. We used Valspar Du Jour.
After two coats of white paint, Olivia’s room suddenly looked so much bigger! I kid you not. And now Joan Rivers would approve of our ensemble.
I have curtain panels ready to hang too, so this window is going to look so much bigger from the boring plain one before.
The Finished Window Trim
Amazing how much a little wood and paint can do, right? Also proof that caulk and wood filler can forgive a lot of sins.
Once the curtains go up and the area rug I ordered arrives, this space will really be singing…er dancing. I mean this is a ballerina room after all.
What do you think? Is DIY window casing a project you could handle?
Robert is already eager to trim our living room and dining room windows, and I’m totally on board.
More DIY Window Ideas
Frequently Asked Questions
Does window trim have to match baseboards?
Are window casings worth it?
So happy I found your post! I’ve been wanting to do something to my bedroom window for ages. The window is a weird size 48″ wide an only 22 ” high (a slider) so this trim application will do wonders for it. My next hurdle is a blind that will fit – the window is only set into the wall about 1″ and it’s metal so hanging a blind has been quite a problem. The current shade is mounted on the outside which is not the most attractive look LOL
Hi! Quick question- why did you not paint the boards before nailing up? Would that not have been easier than painting them while they are already on the wall?
Hi, Kayla! Good question. We wanted a clean smooth finish over the nails.
Thanks so much for the tips, Lauren! I have an extra wide double window in my breakfast area that I would like to make “look” like two windows. I would like to somehow put trim between the two windows so that I can give each window it’s own roman shade instead of using one large roman shade. Does this make sense? And, have you ever attempted something like this? I’m not sure it’s worth the trouble but would love your input. Thanks again!
I have not worked with anything like you are describing. While what you are describing makes sense, I am not sure I would want to make a window smaller or take away from the additional light by splitting it in two. However, I have not seen the window or the space. Have you tried joining the Facebook group I host for decorating ideas? The members there have such a large range of experience, experiments and ideas. They are a GREAT support for things related to this question. I hope you get the look you are looking to obtain. Please let me know how it turns out. 🙂
I hadn’t considered the decrease in light – thanks for pointing that out. I’ll look into your Facebook group. Thank you, and thanks again for sharing your wonderful ideas!
Hi Lauren, I just finished framing my dining room window using your step-by-step post and I have received raving reviews! Thank you! I only wish I would have thought to change out my doorway trim before painting and finalizing everything. 🙁
I plan to carry this look through the rest of the house, but I have 1 triple-window with a half-moon over the top of the center window that has me a little perplexed. I am wondering if the 6″ trim will look too bulky rounded over that half-moon? There is enough space between the windows to add the 1×4 trim, which I think will look really good, just not sure how to top it all off?? I would love to hear your thoughts, or if you have had to do a similar window?
Hi, Erin! Window trim makes such a difference. We have not worked with rounded or half-moon windows. I am sure if the space is there it should look good if you already like the look without the trim. If you could share a picture to my email I may be able to give you a better answer.
Love this look!!!. You guys did a great job! We recently had new windows installed and are doing this inside trim to 15 windows in our house. The tutorial is very helpful. How far does the 1×2 stick out on each side of the top 1×6? 1″ maybe?
Hi, Susan. A little more than an inch but not much more. I never thought to measure that part directly as we just made sure to center it along the top of the window frame. 🙂 I hope you enjoy the look when you are finished. We are so pleased with the big change it made to the whole room.