How to measure for a railing quote

How to measure runs, stairs, corners, posts, and gates, plus the photos and checklist that get you an accurate railing quote faster.

To get an accurate railing quote, measure each straight run separately, mark every corner and end, measure the stairs by riser count and total rise, and note the rail height and how the posts will mount. A hand sketch with those numbers and a few photos is usually all we need. Most quotes go out within 1 to 2 business days once we have them.

Start with a simple sketch from above.

Draw the deck, porch, patio, or balcony as if you were looking down on it. Show the house wall, doors, columns, and anything the railing will start or stop against. It does not need to be to scale. A phone photo of a pencil sketch works fine.

Label each straight run with a letter (A, B, C, and so on). That way your measurements, photos, and our questions all refer to the same spot.

Measure each level run where the railing will sit.

Measure every straight section on its own, to the nearest inch, along the line where the posts will go. If posts mount on top of the deck, measure along the deck surface a few inches in from the edge. If they mount to the side of the rim (fascia mount), measure along the outside face.

• Measure from the house wall or column to the corner, then corner to corner.
• Do not give one total footage. Two 10-foot runs need different posts and hardware than one 20-foot run.
• Note any existing posts you plan to reuse and their spacing.
• Note whether the deck is level or slopes along the run.

Mark every corner, end, and transition.

Corners drive post count and hardware more than length does. For each corner, note whether it is an inside or outside corner and whether the angle is 90 degrees or something else, such as 45 or 135 degrees. For each end, note what the railing meets: a house wall, a column, a stair post, or open space.

For cable railing, transitions matter even more, because the end and corner posts hold the cable tension. Our article on cable railing spacing explains how corners and post spacing affect a cable layout.

Measure stairs by risers, rise, and run.

Stairs are where most quotes go wrong, so take a few extra numbers:

1. Count the risers (the vertical steps), not just the treads.
2. Measure the total rise from the ground or landing to the deck surface.
3. Measure the horizontal run from the face of the top riser to the face of the bottom riser.
4. Note whether you need railing on one side or both sides.
5. Note what is at the bottom: a landing, a pad, grass, or a walkway.

Under the 2021 IRC, Section R311.7.8, handrails are required on at least one side of each flight of stairs with four or more risers. Rise and run let us figure the stair angle, which sets stair post heights and the length of each stair section.

Confirm the rail height before anything else.

Height changes post length, infill, and price, so settle it early. These are the common model code numbers:

Many homeowners choose 42 inches on high decks even when 36 inches is allowed, and some jurisdictions require it through local amendments. Always confirm the adopted code and any local amendments with your building department before ordering.

Tell us what the posts will mount to.

The mounting surface decides which post, base plate, and fasteners we quote. For each run, note:

• Surface or fascia mount: on top of the deck or on the side of the rim board.
• Substrate: wood framing, composite over wood, steel framing, or concrete.
• Thickness: for concrete, the slab or curb thickness and distance from the edge; for wood, the joist and rim size if you know it.
• Existing posts: material and size if the new rail will attach to them.

Every railing system has its own blocking and anchoring requirements, so follow the manufacturer’s current installation guide.

Gates and openings

For each gate, give the clear opening width between posts, which way you want it to swing, and whether it must latch on its own. Gates in a pool barrier need self-closing, self-latching hardware, and local pool barrier rules apply, so check with your building department. If the gate needs access control, see our gates and access control options.

Take photos and run through this checklist.

Good photos save a round of emails. Take these with your phone:

• One from each corner of the area, looking toward the middle.
• A close-up of the deck edge or rim where posts will mount.
• The full stair from the side, so we can see the angle and the bottom landing.
• Each spot where the railing meets the house or a column.
• Any existing railing, posts, or slopes you are working around.

Then check that you have everything in this table before you send:

Frequently asked questions.

Can you measure for me?

We offer on-site design and measuring from Mobile to Pensacola. Outside that area, your measurements and photos are enough for a quote.

What if my numbers are a little off?

Send what you have. We will flag anything that looks inconsistent, and the measurements should be field-verified before the order is final.

Do I need to know the code height?

Tell us where the project is and whether it is residential or commercial. We will quote the height you choose, but your building department has the final say.

When your sketch, numbers, and photos are ready, send them through the quote request form, or see what to send for a faster quote. Browse our railing and handrail lines to pick a style. We supply the materials and are building a nationwide network of independent installers, and homeowners can check for an approved installer by ZIP code on our find an installer page.