05:00AM | 02/18/07
Member Since: 02/17/07
7 lifetime posts
I'll be wiring my workshop under the guidance of the electrical sub that's doing our new house. I've done several smaller wiring projects over the years. But, to keep me from unnecessarily bugging him for advice, I have a couple of questions so far.

When routing the sheathed electrical cable in the attic, (Wood framing), what's the best way? Is it normal practice to just run it directly across from junction box to junction box or should the wiring be secured along the joists and then across to the next junction box? Should I drill 3/4" holes in the joists instead of laying the wiring on top?

It seems that running it directly to the boxes would save on excess wiring, but running it along the joists and then across to the boxes would be neater.




06:12AM | 02/18/07
Member Since: 04/25/05
1918 lifetime posts
The section on NM (sheathed electrical cable) cables in attics refers to this section.

"320.23 In Accessible Attics

Type AC cables in accessible attics or roof spaces shall be installed as specified in

320.23(A) and (B).

(A) Where Run Across the Top of Floor Joists Where run across the top of floor joists,

or within 2.1 m (7 ft) of floor or floor joists across the face of rafters or studding, in attics

and roof spaces that are accessible, the cable shall be protected by substantial guard strips

that are at least as high as the cable. Where this space is not accessible by permanent

stairs or ladders, protection shall only be required within 1.8 m (6 ft) of the nearest edge

of the scuttle hole or attic entrance.

In accessible attics, Type AC cable installed across the top of floor joists or within 7 ft

of the floor or floor joists across the face of rafters or studs must be protected by guard

strips. Where the attic is not accessible by a permanent ladder or stairs, guard strips are

required only within 6 ft of the scuttle hole or opening.

(B) Cable Installed Parallel to Framing Members Where the cable is installed parallel

to the sides of rafters, studs, or floor joists, neither guard strips nor running boards shall

be required, and the installation shall also comply with 300.4(D)."


(D) Cables and Raceways Parallel to Framing Members and Furring Strips In both

exposed and concealed locations, where a cable- or raceway-type wiring method is

installed parallel to framing members, such as joists, rafters, or studs, or is installed

parallel to furring strips, the cable or raceway shall be installed and supported so that the

nearest outside surface of the cable or raceway is not less than 32 mm (1 1 / 4 in.) from the

nearest edge of the framing member or furring strips where nails or screws are likely to

penetrate. Where this distance cannot be maintained, the cable or raceway shall be

protected from penetration by nails or screws by a steel plate, sleeve, or equivalent at

least 1.6 mm ( 1 / 16 in.) thick.


06:47AM | 02/18/07
Member Since: 02/17/07
7 lifetime posts
Thanks Bill!

Would fold-up attic stairs be considered "permanent"?

There is very little room up there because of the truss supports, so there will just be a small area for storage near the scuttle hole no real "walking around" to speak of.



10:51AM | 02/18/07
Member Since: 04/25/05
1918 lifetime posts

Would fold-up attic stairs be considered "permanent"?"

Those are the gray area. In one part of the country they might be, not in another.

In general I would make it neat and logical, while not wasting a unusal amount of coper.

In general I would run along the trusses. Or at one or two areas nail in some 1x4 running bards (or untility 2x4" might be cheaper) at right angles to the trusses.

But say you have a kitchen in one corner diagonaly oposite the panel.

Since you have a large number of loads in the one area then run a running board diagonly across the trusses. and you can pick up other near by circuits at the same time.


Post a reply as Anonymous

Photo must be in JPG, GIF or PNG format and less than 5MB.


type the code from the image


Post_new_button or Login_button

Deep blue grays like the shade shown in this example "have a nautical, serene feeling," says Amy Hendel, designer for Hend... Built on a rocky island in the Drina River, near the town of Bajina Basta, Serbia, this wooden house was cobbled together ... Large steel-framed windows flood the interior of this remodeled Michigan barn with daylight. The owners hired Northworks A... Edging formed with upside-down wine bottles is a refreshing change. Cleverly and artistically involving recycled materials... A Washington State couple called on BC&J Architects to transform their 400-square-foot boathouse into a hub for family bea... Similar to the elevated utensil concept, hanging your pots and pans from a ceiling-mounted rack keeps them nearby and easy... Few projects are more fun than upcycling a vintage piece in a surprising way. Outfitted with a sink and a delicately tiled... The thyme growing between these stepping stones adds a heady fragrance to strolls along this lush, low-maintenance garden ... Decoupage is an easy way to add any paper design to your switch plate, whether it is wallpaper, scrapbook paper, book page... Twine lanterns add pops of crafty—but sophisticated—flair to any outdoor setting. Wrap glue-soaked twine around a balloon ... When securely fastened to a tree or the ceiling of a porch, a pallet and some cushioning make the ideal place to lounge. V... Reluctant to throw away any of those unidentified keys in your junk drawer? Hang them from a few chains attached to a simp... A stripped-down model, sans screened porch, starts out at $79,000. Add the porch, a heated floor for the bath, and all the... Salvaged boards in varying widths and colors make up the dramatic accent wall in this attic space. The high-gloss white of... This garden shed has been decked out to the nines. Designer Orla Kiely created the intimate home for a flower trade show, ...
Newsletter_icon Google_plus Facebook Twitter Pinterest Youtube Rss_icon