How to Turn a Reclaimed Beam into a Fireplace Mantel | Ask This Old House

Ask This Old House carpenter, Nathan Gilbert, helps a homeowner turn a reclaimed mantel into a fireplace mantel.

Time: 4 hours
Cost: $50 - $300
Skill Level: Moderate

Tools:

Shopping List:

Steps:
1. Measure approximately 55-56” off the floor, this is the average mantel height. Make sure the height is at least 12” above the top of the firebox, which is code.
2. Use joints of bricks to mark the center of the fireplace. Do not drill through the brick, it is more difficult and you risk damaging the brick. It will also be stronger to go through the mortar.
3. Find the center of the fireplace using the mortar lines.
4. From the center mark, measure out to the mortar line that is closest to 16” on each side.
5. Next, make sure all marks are level.
6. Drill pilot holes at each mark to make it easier to drill the larger bit.
7. Drill with the larger masonry bit and then clean out the dust and debris with a brush and/or vacuum.
8. Apply epoxy into the hole and insert the threaded rods.
9. Use 2x4’s to secure the rods and make sure they are level while the epoxy cures.
10. Cut the mantle down to the desired length. Use a circular saw or, like Nathan, a two-person crosscut saw to keep authenticity.
11. Use a block plane to clean up 5 of the 6 edges. The sixth edge is not needed as it will be against the wall. Cleaning up the beam will allow a smooth enough surface to apply a finish, without eliminating the marks from the axe.
12. Transfer the measurements from the wall onto the beam and drill.
13. Apply a finish to the five visible sides of the beam. A common finish for old wood was tung oil. It will not darken the beam too much and will help celebrate all the imperfections of the beam. Apply one coat to start and let set for about 15 minutes. Dry off with a lint-free rag. Focus on wiping the high glossy spots and the knots, as they don’t soak in the oil as well. If desired, apply a second coat in 24 hours.
14. Insert epoxy 3/4 of the way into the drilled holes of the beam.
15. Lift the mantle into place and push firmly onto the rods.

Resources:

The other tools and materials Nathan used to secure the mantel to the fireplace, including the drill, block plane, and sandpaper, can all be found at home centers.

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From the makers of This Old House, America’s first and most trusted home improvement show, Ask This Old House answers the steady stream of home improvement questions asked by viewers across the United States. Covering topics from landscaping to electrical to HVAC and plumbing to painting and more. Ask This Old House features the experts from This Old House, including general contractor Tom Silva, plumbing and heating expert Richard Trethewey, landscape contractor Jenn Nawada, master carpenter Norm Abram, and host Kevin O’Connor. Ask This Old House helps you protect and preserve your greatest investment—your home.

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How to Turn a Reclaimed Beam into a Fireplace Mantel | Ask This Old House

[martinhamberger]

This gentleman needs to stick around for years just like Tommy he should be a staple to the program

[bobby-c]

I really enjoy Nathan Gilbert. I want to see him become the next Tommy!

[pufthemajicdragon]

Really good to see Nathan back on the show. This makes me excited for the future of TOH.
I would have cut the mantel long so it extended wider than the chimney and cut out a groove to make it flush with both the chimney and the wall. Buuut that would've taken more than a day. I also would've used carriage bolts to attach it to the chimney so it could be removed - and antique bolts would've complimented the character of the wood.

[toddcriswell]

Glad you like it too because now you’re not getting that off without serious brick damage. Check out Toms video of securing a rail post to the floor. Same principle but removable.

[TotalBoat]

Perfect use of Thixo epoxy. Thanks, Nathan!

[ncooty]

@6:08: Always, always measure from the critical/ alignment point. In most cases, including this one, that means measuring from the center out, not from the end.

[arth.]

Nathan good work, your a good addon to the show

[glennriefenstahl]

Generation Next is working! Nice job Nathan. RIP Austin.

[baspluim]

They cut off the video too soon, he only half-adzed that log

[bryansweeney]

Some mention of fireplace code would have been helpful. Min of 12" above the firebox opening.

[rheffner]

Hey, that's on of the interns! Good for him!

[liamarmstrong]

Just did my fireplace. New stacked stone and simple mahogany boxed out mantle with an oil finish.

Wish I could have found a beam this guy got.

[suehardie]

Just wondering what sort of instant nail Adhesive you use doing the same thing put on wood 🤔

[mattlocke]

So whats the plan to remove the mantle when needed?

[KundelCrane]

check out our Restorer tool. It is designed specifically for reclaimed wood cleanup without destroying the character!

[oogrooq]

Which one do you think is the 'top'. Either way, good for them.

[timskufca]

SUGGESTION: this is where an interior designer would have added a little finesse. The beam should have been situated with the surface of the mantel in the wide direction. Then it's calling out for a couple of corbels to act as a structural element. The way it was installed it looks fake - like you used epoxy to glue it in place (even though that's what was done, an old beam like this should at least look authentic).

[twsbrlxlldmoney]

Rumor has it Nathan is still hueing and Guy is telling him thanks

[twdietri]

What would the size of hole in the masonry and threaded rod be?

[justinwoods]

I'm actually wanting to buy a draw knife i see another of those tools used today besides the two man saw