How to Build a Deck Railing | Ask This Old House

In this video, Ask This Old House carpenter Nathan Gilbert builds and installs a railing for deck stairs that will match the original railing around the rest of the deck.

Nathan Gilbert and Mauro Henrique make a house call to help a homeowner build, install, and paint a deck stair railing. The stair entrance to the deck on the front side of the house has a railing, but the backyard entrance does not. This troubled the homeowner because she has a young son that loves to play in the backyard, and she’s worried he might fall off the steps. Nathan agrees, there are four risers and any stairs that have over two should have a railing for safety. Since there are railing throughout the rest of the deck, Nathan plans to build a replica railing to match so it looks like they were always there.

Time: 5 hours
Skill Level: Moderate

Shopping List:

Tools:

Steps for building a deck railing
1. For material, Nathan picked up wood made of fir, which is a great material for decks and is water resistant. It also takes paint better than pressure treated wood does.
2. Remove the bottom stair deck boards.
3. To find out what you need to notch out of the post, use one of the 2x4’s and plumb a level from the stringer. Make a mark on the inside of the level and take a measurement for the cut.
4. Take the notch out of the posts.
5. Make the top of the post from 45 degree cuts all around.
6. Drill a couple pilot holes at the bottom of each post for the structural screws.
7. Put the post in place, make sure it is level and plumb.
8. Secure posts by screwing in the structural screws.
9. Find the angle and length of the bottom and top rails by laying the two pieces together on the nose of each stair tread, and mark where they hit each post.
10. The angle of the rails will be the same angle the balusters will need to be cut.
11. Make the cuts.
12. Spray the ends of the balusters and rails with primer.
13. Assemble the balusters to the top and bottom railings.
14. Install it to the posts.

Where to find it?
Nathan built the deck stair railing out of fir decking in a variety of sizes, including 2x4”s for the top and bottom rails, 4x4”s for the posts, and 2x2”s for the balusters.

Expert assistance with this segment was provided by William C. Gilbert Carpentry.

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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 Build a Deck Railing | Ask This Old House

[briancnc]

Some say Mauro never made it back from the paint store ...

[awaara]

Legend has it Mauro is still at the paint store

[davidharris]

I’d paint those posts before mounting them. A lot easier than masking everything and the bending to reach with the brush.

[jl]

I noticed the new lenses and camera. Looks good!

[TheRealNosferatu]

Probably wouldnt have been a bad idea to paint the posts before they go in. That way the end grain thats touching the ground wont allow as much water and will prevent rot

[thelostarchivesserialvault]

Seriously, setting a pine post that you just cut off and notched right on the dirt with zero treatment. Those rails will rot out pretty quick at that point. I would have built up several layers of the pvc material to make the post and then cut and sanded it to fit the same dimensions. At the very least Cedar would have been a better choice. I typically use heat shrink sleeves on any wooden part that is on or in the ground. You should always tape seal the tops of joists. Things last longer if you take the time to protect them.

[Jddlincoln]

So you prime the ends of you’re balusters but not the fir posts that are in contact with the ground……

[wadup]

Great work. And, maybe it’s because I usually watch from my phone, but it looks like you guys got some new cameras! Great resolution and work as always!

[ehatelife]

I think you guys should review the international deck building code. 4x4 post can not be notched

[scottyellis]

Love the video's, love the show on PBS, been watching for 30 years. 👍🏻

[TechmattOfficial]

Mauro definitely lost that block of wood

[ryk]

Absolutely crazy that you didn't paint those cuts

[rafaelsays]

Ain’t no one better than Mauro on paints

[the_jonathan_o]

I would've loved to see it painted.

[platipuss]

no ground contact PT for those uprights? You could have AT LEAST used some VG cedar.

[hilbert]

Oh the army of arm chair quarter backs and YT experts on these commentaries. Too funny 🤣.

[billbriggs]

Hand rails on stairs have a requirement for "graspability". This does not meet that requirement. Usually the handrail is installed after the construction of the guard constructed in this video. Also the building code does not "suggest" 4 inch space. The code require the spaces to be no wider than 4 inches.

[karlhungusjr]

05:20 they look like they are on a greenscreen.

[realjacob]

"stainless steel strips really easily"
Then gives her a drill and not an impact driver. 🤣

[peterhanson]

Why do you pump the trigger on the drill/driver? I was always told to drive the screw all the way in before releasing the trigger to save wear and tear on the drill.