With the arrival of summertime we’ll all be spending more time on our decks / terraces / rooftops and nothing gets in the way of a perfectly beautiful sunset like an overdesigned guardrail. So we think it’s a good time to share some architectural guardrail details. We like these details because they’re everything they need to be and nothing more; they’re attenuated, durable and unobtrusive. Let us know what you think and share what you know.

First, let’s start with a very basic interior steel guardrail. It uses cold-rolled ½” thick x 2” wide steel frames; inside the frames, 3/8” diameter horizontal steel rods are welded to the verticals at 3 ½” on center.

Locally building codes govern the overall geometry; this particular project is governed by the Seattle Amendments to the International Residential Code. The minimum height is 36″ (or 34” at the open side of a stair) and the maximum space between the horizontals is 4”.

The welded connection at the horizontals leaves a small bead of steel between the rods and the verticals. As long as the beads are consistent from one horizontal to the next, we don’t mind the look – in fact it’s a nice authentic detail (it’s also cost-effective). Square-drive, flush wood screws attach the guardrail assembly to the floor; additional blocking is used at the floor in these locations for added strength.

There are a variety of conditions and related details where this guardrail intersects with sloped guardrails (at stairs) or handrails which we’ll cover in a future post.

The cold-rolled steel is hand-rubbed with Scotch Brite to preserve the mill finish, then waxed with a clear paste wax, we like to use Briwax. A larger version of the detail below can be found here.

A modified version of this guardrail eliminates the welded connection between the horizontal rods and the verticals. By tapping the verticals, the rods can be threaded and reverse threaded into the joint, thereby eliminating the weld bead. This detail is super clean but also a bit fussy and more expensive.

Another evolution of the interior steel guardrail adds a 1″ x 3″ stick of ipe wood to the top rail. Visually, it warms up the guardrail and brings an additional texture to the feel of the guardrail. For the application below we wanted to warm up a rather sterile (and existing) hallway.

Outdoor guardrails tend to be much longer and subsequently can easily consume a great deal of material. We’ve developed a kit-of-parts over the years to reduce the amount material and connections needed for long expanses of exterior guardrail.

Galvanized ½” thick x 2” wide steel posts are welded to 4” long base plates which allow (4) lag screws to keep the posts stiff. This eliminates the need for a top and bottom steel frame. A 1” x 3” stick of solid ipe holds the tops together and provides a nice tangible rail.

For the horizontals we like to use a 3/16” diameter stainless steel cable. Holes are drilled every 3” oc at the verticals and the cable rail can run right through – eliminating any fussy connection details. The end terminations of the cable rails vary from one manufacturer to the next, we like to use Feeny – they have a couple of systems that are clean, modern and cost-effective. A larger version of the detail below can be found here.

A modified version of our exterior rail allows the system to be mounted to the side of the deck. This application requires the rim-joist to be beefed up, but it buys back some additional surface area on the deck.

That’s the scoop on guardrails. Sharing information = good. Hit that comments button.
Cheers from team BUILD.