Using PVC conduit

[Sleepydog]

Can sch 40 PVC be run along outside wall of a house or do I need sch 80. How many feet can be run before an expansion joint is required

 

[AC Power]

Yes, schedule 40 is fine. It's otherwise called rigid PVC. Distance before an expansion joint?....How long is your run?

 

[Sleepydog]

Total run about 50 ft. Plan to run high under an overhang but along the way have tees down to outlets

 

[AC Power]

50 feet is not long enough to worry about intermediary expansion couplings. The assembly (as a whole 50' run) will expand on it's own as a whole length without buckling somewhere in the center of the run. Use the 2-hole PVC straps/clamps that are designed for the support of PVC, your fine. Use PVC cement, no need to worry about PVC cleaning solvent.....it's efficacy is questionable.

 

[He who knows]

50 feet is not long enough to worry about intermediary expansion couplings. The assembly (as a whole 50' run) will expand on it's own as a whole length without buckling somewhere in the center of the run.

18 thou per degree F.

So 1¼" between 30° and 100°

 

[AC Power]

Those calculations are likely correct (18 thou per deg F), but on a 50foot run, the expansion can occur at the ends. If there was 200 feet of PVC conduit, the expansion that occurs in the center of the run (at approx 100ft) has nowhere to expand easily enough, and thus, buckle the center of the conduits overall entire run. It is an interesting figure you've commented on....I'll remember that, 18thou per deg F.

 

[He who knows]

Those calculations are likely correct (18 thou per deg F), but on a 50foot run, the expansion can occur at the ends.

Only if it's constructed in a way which accomodates expansion and contraction.

 

[AC Power]

That's right, I agree with you. Each end of the run would have to have some room for movement, otherwise, I guess SleepyDog can just go-ahead and put an expansion joint in the middle for safety sakes.

 

[He who knows]

I would. Or more than one.

Actually, I'd use steel conduit, not PVC, but that's another matter, and I accept that it's not as DIY-friendly....