SW9racer 262 Posted May 21, 2019 Looking to bury a 10/2 power cable for a 30 amp 110 circuit around the patio. Can I directly bury the UF-B cable, or do I need to encase it in a run of 1/2” pvc conduit? There is no chance of the buried cable being damaged, it will be several inches below sand, then below 2 inches of river rock, running along the edge of the patio cement foundation. (And no frost down south) Thanks! Quote Share this post Link to post Share on other sites
Golf battery 1,223 Posted May 21, 2019 Hey. Its your property. Do whatever you want. Personally. I’d put it in conduit. Quote Share this post Link to post Share on other sites
Sniper 6,372 Posted May 21, 2019 6 minutes ago, Golf battery said: Hey. Its your property. Do whatever you want. Personally. I’d put it in conduit. I'd agree with that. Primarily because he might know where the cable is buried, but the next owner won't, so hitting the conduit while digging, instead of going through the actual wire, might prevent a fireworks show..... or worse... 1 Quote Share this post Link to post Share on other sites
Tunaman 548 Posted May 21, 2019 Must be 18 inches to the top of the conduit. I wouldnt do it any other way. I would check with your local inspector to see if they allow buried cable without conduit. Some do and some dont. You also have to put metal tape 12 inches below the surface so the line can be detected in the future. 2 Quote Share this post Link to post Share on other sites
Sota 1,191 Posted May 21, 2019 I was gonna say, there's marker tape you should use as you layer up on top of whatever you wind up running. Quote Share this post Link to post Share on other sites
Heavyopp 167 Posted May 21, 2019 5 hours ago, Tunaman said: Must be 18 inches to the top of the conduit. I wouldnt do it any other way. I would check with your local inspector to see if they allow buried cable without conduit. Some do and some dont. You also have to put metal tape 12 inches below the surface so the line can be detected in the future. You sure it's 12" below the surface -- I've installed plenty of buried street light wire, all inspected -- the marker tape was always to be installed 12" above the wire -- didn't matter if it was direct burial or conduit -- this was in sayreville Quote Share this post Link to post Share on other sites
Ray Ray 3,566 Posted May 21, 2019 7 hours ago, Tunaman said: Must be 18 inches to the top of the conduit. I wouldnt do it any other way. I would check with your local inspector to see if they allow buried cable without conduit. Some do and some dont. You also have to put metal tape 12 inches below the surface so the line can be detected in the future. This But I would run outdoor conduit. This way you can add circuits or replace the circuits you ran. Quote Share this post Link to post Share on other sites
SW9racer 262 Posted May 21, 2019 Will do! For the pvc conduit, use silicone for the connections, or go with that blue pvc cement? And as it’s in conduit, can I use regular NM-B cable instead of uf-b? Quote Share this post Link to post Share on other sites
Ray Ray 3,566 Posted May 21, 2019 42 minutes ago, SW9racer said: Will do! For the pvc conduit, use silicone for the connections, or go with that blue pvc cement? And as it’s in conduit, can I use regular NM-B cable instead of uf-b? The PVC cement will be gray. Use regular THHN #10 and use #12 for the ground. Quote Share this post Link to post Share on other sites
SW9racer 262 Posted May 21, 2019 36 minutes ago, Ray Ray said: The PVC cement will be gray. Use regular THHN #10 and use #12 for the ground. Stranded or solid? I have not used thhn before, is this recommended as it’s cheaper than nm-b? Will all 3 fit in a 1/2” conduit? Thanks! Quote Share this post Link to post Share on other sites
djg0770 481 Posted May 21, 2019 20 minutes ago, SW9racer said: Stranded or solid? I have not used thhn before, is this recommended as it’s cheaper than nm-b? Will all 3 fit in a 1/2” conduit? Thanks! http://www.elliottelectric.com/StaticPages/ElectricalReferences/ElectricalTables/Conduit_Fill_Table.aspx Quote Share this post Link to post Share on other sites
Ray Ray 3,566 Posted May 21, 2019 4 hours ago, SW9racer said: Stranded or solid? I have not used thhn before, is this recommended as it’s cheaper than nm-b? Will all 3 fit in a 1/2” conduit? Thanks! Stranded, you can fit all 3 plus extra curcuits for outlets and lights. If you need help, let me know. Quote Share this post Link to post Share on other sites
PeteF 1,044 Posted May 21, 2019 UF-B can be direct buried. As @sota wrote there are markers (https://www.amazon.com/Morris-Products-Underground-Printed-Electric/dp/B01LVW0U73) that make the install easier to detect/avoid damaging. Whatever you do pick ONE. Either use direct burial cable or lay pvc pipe with thhn. Don't try to pull NM cable thru a conduit. Unless the conduit is ridiculously large you will regret it. Quote Share this post Link to post Share on other sites
njJoniGuy 2,131 Posted May 22, 2019 Unless you get Mayor Pete to do the install for you. Rumor has it that he can suck a golf ball through a garden hose. 1 Quote Share this post Link to post Share on other sites
Tunaman 548 Posted May 22, 2019 I always use one size bigger schedule 40 pipe than you think you need. Makes for a simple pull and leaves room for upgrades or repair in the future. I have a bunch of puling strap if you need it. Quote Share this post Link to post Share on other sites
SW9racer 262 Posted May 22, 2019 Awesome info everyone! As recommended I will up the run to 50amp 220v. Outside I will go #8 thhn in 3/4” pvc conduit. One end to spa, the other a “gfci squareD spa 50a box” on outside wall of house. From there I will go #6-3 nmb thru attic to the main panel with a standard 50amp breaker. Did I miss anything? Quote Share this post Link to post Share on other sites
Tunaman 548 Posted May 23, 2019 I would run 8-3 w/ground. Just in case you need a 120 volt line you will have the neutral. Quote Share this post Link to post Share on other sites
SW9racer 262 Posted May 23, 2019 Another quick question. The last 3 feet on the nmb (6-3) run will be thru pvc conduit from the roof eve to the gfci box, mounted on the outside of the wall. Do I need to strip the outside layer off the nmb wire for that 5’ running in the conduit outside? Quote Share this post Link to post Share on other sites
Tunaman 548 Posted May 23, 2019 You cant use NM in conduit. THHN or THWN outside. Quote Share this post Link to post Share on other sites
SW9racer 262 Posted May 23, 2019 10 hours ago, Tunaman said: You cant use NM in conduit. THHN or THWN outside. Can I use 6-3 UFb to run in the 3’ conduit outside then continue it on in the attic to the main box? That is rated for outside and inside. Quote Share this post Link to post Share on other sites
Tunaman 548 Posted May 24, 2019 Before we go any further, what are you wanting to power up outside? Total appliances and the amperage draw of each Unread Content s the easiest. Quote Share this post Link to post Share on other sites