Your Complete Guide to Installing Quarter Round Molding

worstontheblockJune 8, 2021

Looking to put the finishing touches on a newly installed floor? Want to hide those gaps between the floor and your molding? Quarter round it is!

Quarter round is shaped literally like one-quarter of a circle (hence the name). It has two flat sides in a 90 degree angle that sits along your floor and walls, and a rounded piece that is visible when installed.

Installing quarter round is an easy and inexpensive fix when you are unable to remove all your molding before laying new floors.

No matter how close you get your new floors to the edge of your existing molding, there will always be a noticeable gap and uneven edges.

The quarter round fills that gap.

Luckily, installing quarter round is a simple DIY that can be completed in just a few short hours and creates a beautiful finished look.

We recently refinished our floors in our bedroom using simple peel and stick tiles as a temporary fix before a (hopefully) big reno down the line.

Check out how we installed the new floors here!

But we were unable to remove the moldings first as the previous floors were installed by butting them up against the molding. We would have damaged the floors, walls, and moldings trying to remove them.

This, of course, would cause a chain effect as we wouldn’t have been able to lay the peel and stick floors over damaged floors, would have had to repair the floors, fix the walls, get new molding…

The list goes on.

And I wasn’t up for that much work for a temporary fix!

So the very simple solution was just to butt it up to the molding again and add some quarter round. And we have it in most of the rest of the house so it all matches 😆.

What you’ll need:

quarter round
saw
brad nailer or hammer and nails
spackle
sand paper
paint
measuring tape
pencil

Notes on supplies:

When shopping for my quarter round, I came across a composite quarter round that was much less expensive (the cost of wood these days! Woah!) AND is made with recycled materials.

You can sand, cut and paint it just as you would regular wood, and a bonus for us is that is was already white, so I didn’t have to go crazy with several coats of paint.

Obviously, if you want stained wood, purchase the wood. Check out our wood buying mistakes to avoid here.

A chop saw is ideal for this project but you can get the job done with a circular or even a hand saw with a miter box.

Always take every safety precaution and read all directions first when using power tools!

Here’s how you do it:

1. Sand

A quick sand to your quarter round will remove any scuffs, dings and imperfections that may be present.

You can use plain old sheets of fine grit sand paper, or a palm sander may work for this as well if you keep a steady hand.

Whenever you sand something, if possible, work outside and with a mask on. You really don’t want any of those tiny particles getting in your lungs.

The composite material did have some dings and scratches to it, so the sanding took those off easily and creates a nice clean surface, but you really don’t have to go crazy here.

Work in one direction (with the grain if you’re using wood) so you don’t get weird patterns from the sand paper.

Then wipe off the excess dust with a damp rag.

2. Stain or paint

You’ll want to match your quarter round to your existing moldings, so depending on what you already have on your moldings, go with that for staining or painting.

Unless, of course, you want to change the whole thing by painting or staining a completely new color.

Our moldings upstairs were already painted white from a prior tenant before we purchased the house, so we are sticking with that for now. We used a white satin finish paint that we had leftover from our mantel project.

A satin finish will be more “wipeable”, which you’ll want for baseboards.

Give it a coat or two, depending on how well it covers.

Since the composite material was already white, I just needed to do one coat of paint (score!)

Allow to dry completely.

3. Cut your quarter round

Cutting quarter round can be tricky, and every room has it’s own challenges.

I love to work in separate processes, meaning I like to cut everything, nail everything, spackle everything, etc.

BUT for this DIY, especially if you have a lot of corners and doors, you will most likely have to nail some of your boards down before continuing to ensure that you have the proper measurements for the next piece.

This was certainly the case in our room, where we have four doors and several corners. It helps to have your mitersaw nearby.

We put ours right out on the balcony. It made a mess but was totally worth it.

So keep this in mind, continue to assess and nail down your boards as needed.

There will most likely be multiple different types of cuts that you’ll need to get your DIY completed.

Here’s a few pointers to get it done:

Scarf joints

The scarf joint is made to join two pieces of shorter quarter round to make a longer piece seamlessly.

You’re simply going to set your saw to a 45 degree angle and cut the joining ends at the same angle so they fit together with minimal joint visible.

This is how we turned our 6-ft lengths of quarter round to fit our 26-ft long wall, and you barely notice the seams, especially after spackling, sanding and painting.

This is a simple process and is a good one to know about for any DIYer and DIY project. It is how we created our above-the-17-ft-window-shelf using regular size boards.

Doorways

You want to make a 30 degree cut around any doorways (or where the edge will be exposed, like on stairs).

This is simply done by measuring the length of quarter round needed and cutting a 30 degree angle at the end so that the longer side is towards the back.

So for a cut where the door is on the right hand side of the quarter round, you want to put your saw at a 30 degree angle so the blade is facing the direction that the front of the blade is to the left if you’re looking from above.

Measure the quarter round on the left side of the cut, mark and cut away.

Corners

The corners are the most confusing, in my opinion. We found the most success when we just moved the base of our miter saw to create the angle we’re looking for.

If you’re using a miter box and hand saw or a circular saw you don’t have to worry about the multiple angles. But simply moving the base made the process a lot easier.

So to join two corners, you need to cut two 45 degree angles that will meet together, assuming your wall is square.

If your wall is not square, you can go through the trouble of figuring out what degree angle you have and cut it appropriately, but it’s not totally necessary if you’re using spackle.

Our walls are definitely not square, but we just filled in the joint and made it nice by sanding. This (in my opinion) is so much easier.

A professional carpenter would tell you the right way to do it, but I am your average homeowner just trying to make a few improvements without losing my mind. If you’re with me, grab a bucket and lets go 😂.

For an outside corner, the left side will be cut like this \ and the right side will be cut like this /

And for an inside corner, the left will be cut like this / and the right side will be cut like this \

Tip: cut the pieces longer than you need them so you know you have the correct angles.

Then when the corners match up correctly, you can measure and cut to the right size without having to worry about making an incorrect cut because you already have a template or cheat sheet of sorts right there in front of you.

THEN measure from the shortest side of your cut to the next inside corner.

Seriously, just cut it long. You can always take more off, but you can’t add it once it’s gone. (Well, you can always do a scarf joint! But you get the idea!)

4. Nail

To secure the quarter round to the molding, you really want to use a nail gun if you can get your hands on one.

It will make the job so much easier and decrease the risk of damaging the area around your quarter round if you are not so great with a hammer.

That being said, you absolutely can get this job done with a hammer and nails. You can use your driver to drill a pilot hole, hammer in a finishing nail and then use a punch to sink the nail.

It is definitely doable, but it will take a lot longer to complete.

We borrowed a nail gun from Brad’s dad. Ask a friend, neighbor, family member if you could borrow theirs, OR you can rent one from your local hardware store.

Or if you have the funds it is a great tool to have around. ☺

Make sure that the quarter round is secure and in the proper place, and then get nailing in whatever method you’ve chosen.

Place several nails in each board so it is very secure. You also want to make sure that the nails sink below the quarter round. There should be a way to adjust your nail gun to create this, or use a punch if you went the hammer and nails route.

Go along your room, ensuring all pieces are nailed in place and the corners are as flush as possible.

5. Spackle

Now it’s time to fill any holes and joints. You can smear it on with a tool, making sure it gets into the gaps and corners. It will dry hard and you can then sand it, so it’s better to have extra than not enough.

Use a paper towel, putty knife or just your fingers to wipe the excess and smudge it smooth.

Allow it to dry completely. Read the directions on your bucket. We let ours set overnight.

6. Sand

When the spackle is completely dry, you can sand off the excess, creating a nice smooth surface.

I find this part very satisfying. Everything smooths out and comes together.

Always wear a mask when sanding, and clean up as much of it as you can so those tiny particles aren’t flying around and being sucked into your lungs. You don’t want those in there!!

Then wipe your moldings down with a damp rag or paper towel to remove all the dust from sanding and to create a nice smooth surface for your paint and allow to dry.

7. Paint

Ok, so yes, we already painted. But we just have to go over those spots that we sanded and it doesn’t hurt to give it a final once-over so it’s all uniform.

That being said, if you just put down new floors, DO NOT GET PAINT ON THEM! Be very careful.

I simply painted the top of the quarter round where the spackle was, but if you want to do a thorough coat be sure to tape and protect your new floors well.

Then allow to dry and you’re all set!

Recap

You now have a room that looks finished with it’s fresh new floors, quarter round, and no seams showing at the moldings!

Remember the simple steps:

Sand
Paint
Cut
Nail
Spackle
Sand
Paint

And you have beautiful new quarter round ☺

We hope you enjoy this simple DIY as much as we did. It really made our new floors look so much better, finished and clean, and was so easy and inexpensive to complete.

Questions? We’re here!

Tell us in the comment box below how you finished your floors
and how much spackle you used on your quarter round 😂

Your Complete Guide to Installing Quarter Round Molding