Wire type for underground?

[deepstuff]

What type of wire do I need to pass underground from my house to garage about 20 feet? Should it be ran inside a pipe? Should I use some sort of pipe for slab penetraton?

 

[RickP]

MHF is probably your cheapest option. It's direct burial without conduit outside, but it needs conduit inside the house and garage.

 

[nadogail]

Agreed, it MHF needs protection any time it is not buried (under round or in a wall).

 

[pattenp]

In Canada I see people post the use of TECK90. I don't know what your availability of MHF is.

 

[deepstuff]

Ok lots of time to figure wire out. For now what size conduit should I put through concrete slab before we pour?

 

[pattenp]

Conduit size depends on the wire size used for the amount of power needed. Not knowing the power required and assuming a typical homeowner garage, I'd say stub up 2" PVC at least. Do you know how much power you want in the garage?

Edit: I suggest doing conduit all the way underground and using THHN/THWN wire. I believe the Canadian type for THHN/THWN is T90.

 

[deepstuff]

I'll b connecting to 6/3 wire already ran to corner of attached garage. Then 30 feet to detached. I figure 60 amps.

 

[pattenp]

I'd use no smaller that 1.25 inch PVC conduit to be on the safe side.

 

[theoldwizard1]

I'll b connecting to 6/3 wire already ran to corner of attached garage. Then 30 feet to detached. I figure 60 amps.

If this is copper cable, you need to be careful using MHF because it is aluminum. For 6 gauge I would recommend Polris connectors similar to this

There are special coatings/grease for aluminum cable when you put it in a connector.

UF-B (direct bury Romex) does come in 6/3 also and then you can use split bolts.

 

[nh_yota]

I'm a big fan of using conduit as opposed to direct burial because if you need to re-run the wire for whatever reason you just pull it through with no digging required. PVC conduit is cheap.

 

[tfi racing]

Good tips,but the recommended US wire not used in Canada.Your choices are Teck90 or ACWU cable which can be direct buried,or NMWU90 cable or individual RW90 conductors in PCV conduit.

 

[alfredeneuman]

What type of wire do I need to pass underground from my house to garage about 20 feet? Should it be ran inside a pipe? Should I use some sort of pipe for slab penetraton?

It all depends on what your amperage requirements are.
Some people immediately suggest the "GJ default" MHF route, which would not always be the right choice.