electrical before or after spray foam

[bdog]

I am getting a 50x50 steel building built next week. I am going to go with the spray foam insulation. Should I do the electrical first and have them spray over it, or insulate first and then put the electrical on top?

 

[jmastersinc]

Are you planning on using Romex or conduit?

 

[CraftsmanOnCall]

Electrical first.

 

[bdog]

Are you planning on using Romex or conduit?

It is a steel building and I am not putting any covering on the interior walls so conduit.

the insulation people say they have seen it done both ways.

 

[jmastersinc]

If you are running conduit than before, and if you are running EMT I would suggest using compression connectors as appose to set screw type. If you are going to run PVC this won't be an issue but is a little more expensive. Also run some extra to junction boxes for future use, I don't know how may times customers have been mad when we have to run conduit out side there walls or cut into a wall.

 

[DRJZ1974]

Electrical first. I have spray foam in my garage. Incredible insulation, but all electrical outlets and cable outlets I have added (garage was built before I bought it) have needed to be run in surface mount raceways.

 

[rikmeister]

i vote for electrical first

 

[tcianci]

Personally, I would do the electrical first. You may want to talk to your local building dept. They may not differentiate between your type of construction and a typical frame which usuallly requires the frame to be wired and plumbed before any insulation can be done. The reason for this is to make sure the structure has not been compromised by an over-zealous tradesman with a sawsall or hole-hawg. If you do opt for the wiring after the foam, technically none of the wiring job is hidden by the insulation so it is possible to do it that way and still be properly inspected, just check with the guys with the ballpoints, they sign your building card.

 

[GSSFC]

It is a steel building and I am not putting any covering on the interior walls so conduit.

the insulation people say they have seen it done both ways.

Just so you know, according to the current building codes, spray foam insulation cannot be left exposed, it must have at minimum an ignition barrier, and depending on the location, a thermal barrier as well.

You might want to check with the local code enforcement.

Tim

 

[tab2]

Just so you know, according to the current building codes, spray foam insulation cannot be left exposed, it must have at minimum an ignition barrier, and depending on the location, a thermal barrier as well.

You might want to check with the local code enforcement.

Tim

I have seen a few tens of million dollar houses with this NOT the case in MA. .

 

[blkhonda1991]

I have seen a few tens of million dollar houses with this NOT the case in MA. .

exposed spray foam insulation in houses?

 

[GSSFC]

I have seen a few tens of million dollar houses with this NOT the case in MA. .

Just because you have seen it, does not mean it is correct. I don't agree with the code, just passing the info along. There are paints that are clear and white which are approved thermal and ignition barriers, which still make the foam look "exposed".

Tim

 

[tab2]

I am taking about houses that overbuilt to the extreme, it is usually in attics which is probably the loop hole, not defined as living space?

 

[blkhonda1991]

I am taking about houses that overbuilt to the extreme, it is usually in attics which is probably the loop hole, not defined as living space?

attics are not livable space therefore its techincally not exposed insulation since the drywall ceiling is the barrier between the living space and insulation

 

[ilateapex]

We had to apply the spray ignition barrier on the spary foam in the attic per the IRC on some Navy housing we are building. The foam was applied to the roof deck and the attic was conditioned space.

Michael

 

[tab2]

http://www.icynene.com/faqs/#aa27

not sure how you plan to deal with the exposure issue...