# What is PVC support spacing in the NEC?



## NDC (Jan 12, 2016)

Just curious what your spacing requirements are for supporting PVC conduit.


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## wildleg (Apr 12, 2009)

(2011) .


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## cabletie (Feb 12, 2011)

Table 352.30Support of Rigid Polyvinyl Chloride Conduit (PVC)
Conduit Size Maximum Spacing Between Supports
Metric Designator	Trade Size mm or m	ft
16–27	1/2–1 900 mm	3
35–53	11/4–2 1.5 m	5
63–78	21/2–3 1.8 m	6
91–129	31/2–5 2.1 m	7
155	6 2.5 m	8


Also within 3' of a box.


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## cabletie (Feb 12, 2011)

That didn't paste right. Picture might be better.


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## joebanana (Dec 21, 2010)

How do you support 100' conduit every 8', and keep within 3' of a coupling or connector?


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## davegerver (Dec 5, 2014)

8' is a minimum strap every 2' if you want 

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## davegerver (Dec 5, 2014)

sorry maximum not minimum 

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## NewElect85 (Dec 24, 2017)

We had a fire alarm project a few years back that had an existing rack spaced 5' it was decided to just run1-1/4 PVC to avoid having to add additional supports.


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## joebanana (Dec 21, 2010)

davegerver said:


> 8' is a minimum strap every 2' if you want
> 
> Sent from my SM-G950U using Tapatalk


 But, I don't want to. I want to be compliant, but not over-kill it.
This is an actual work place scenario. "New" foreman wants EMT conduit supported every 8', period. On uni-strut. I think he's effin w/me.


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## Malywr (Jan 23, 2018)

Securing and support PVC. 352.30 depend on size of your conduit. Consider also 352.44 expansion fittings. EMT 358.30B. Maximum 10’ or less


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## 220/221 (Sep 25, 2007)

davegerver said:


> .... strap every 2' if you want



But it will still sag if horizontal


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## Bird dog (Oct 27, 2015)

Malywr said:


> Securing and support PVC. 352.30 depend on size of your conduit. Consider also 352.44 expansion fittings. EMT 358.30B. Maximum 10’ or less
> 
> 
> Sent from my iPhone using Tapatalk


Fastened & Supported are two different things.
352.30(A) Securely Fastened (within 3' of...terminations)
352.30(B) Supports (according to T352.30)


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## tgiamboy (Sep 10, 2018)

*Table 352.30*

Table 352.30 Support of Rigid Polyvinyl Chloride Conduit (PVC)

Conduit Size Maximum Spaces Between Supports 

metric Designator..... trade size...... mm or m ...... ft
16-27...... 1/2-1..... 900mm..... 3
35-53 .. 1 1/4 -2.. 1.5 m....... 5
63-78... 2 1/2 -3... 1.8 m..... 6
91-129.... 3 1/2 - 5.... 2.1 m.... 7
155.......... 6..... 2.5 m..... 8


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## paulengr (Oct 8, 2017)

joebanana said:


> How do you support 100' conduit every 8', and keep within 3' of a coupling or connector?


Easy but you have to pay a little attention to material and labor costs. Once you get above 1" trade size generally speaking supports are starting to get to be substantial so supports drive costs more than conduit. So just cut a couple feet off all your conduits to 8 foot lengths and run the support spacing every 8 feet as demanded.


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## Malywr (Jan 23, 2018)

Bird dog said:


> Fastened & Supported are two different things.
> 
> 352.30(A) Securely Fastened (within 3' of...terminations)
> 
> 352.30(B) Supports (according to T352.30)




Thank you for clarification... 
my point was depend on size of conduit support spacing change... same as TGIAMBOY was explaining 


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