Main Beam of a Residential House

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Thanks, Dan.
With the hot water heater, dryer , central heat and oven in gas, I recalculated the load according to the NEC examples in Chap 9, I came up with ample amps to spare. This is as per your suggestion and I suggested this to the HO which he agreed.
With your comment about the swim pool, Cal Title 24, and the floor heater,you are making my job quiet easy.
I also called the Poco (PG&E) yesterday, that I 'd install a 200 amp service and they have no objection.
I had an addition job one time where the PoCo after visiting the job site suggested to change the service to 200 amp to which I complied.
I learned a long time ago it is best not to argue with th inspectors.
Thanks Dan.
 
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I woulld like to ask if the inspectors will have any objection having different brand in main panel and subpanel provided of course breakers would be the same brand installed in each panel. The reason behind this is I could install more breakers in the subpanel for the same amp rating in another brand in comparison with the main panel.
 
bencelest said:
I woulld like to ask if the inspectors will have any objection having different brand in main panel and subpanel provided of course breakers would be the same brand installed in each panel. The reason behind this is I could install more breakers in the subpanel for the same amp rating in another brand in comparison with the main panel.
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They couldnt care less
 
bencelest said:
Thanks Steve. That's a relief.
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How many breakers were you planning to put in the panel? 50? 60? This sounds like a really big house you're building for this guy.
 
Well actually I have not figure out to devide the load in half yet. Remember I asked the question if I could drill a hole to the main beam? The main beam is located right in the middle of the 1st floor of the house. I find out that I can get away from drillingthe main beam .
if I can route the feed wire to the submain at the attic of the 2nd floor and down the wine room on the other side of the main beam. But the jacuzzi, kitchen appliances and the heavy loads are located in this area and I can't put much load to the main service wiithout using much longer wires. This house is shaped like a U and the main sevice panel will be located at the tip of th U.
I got the OK from the PoCo to install a 200 amp service when I told them that the water heater, stove, central heat and dryer will be gas.
With the new code that says this and that will be dedicated, I am afraid that I may run out of space to put the circuit breakers so I was looking for a submain that would carry the max of breakers for a hundred amp submain. I found one.
I don't want to happen to me like on his other house which I ran out of space and I had to fix it somehow.
Which brings me a new question.
Where is a good place for the GFI and the emerg shut off for the jacuzzi be if the code says within 5 feet from the edge of the tub? The jacuzzi will be located in the master bedroom.
 
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bencelest said:
This is the 1st time I will be wiring a 400 amp meter/main and I think that that is just too big for the load it carries.
I told the owner that I have never seen a 300 amp combo meter main and I checked 3 electrical supplies . The owner told me that an electrician can produce one or buy one.
I told the owner if the electrician can produce one then hire him.
He stil retains me.
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The other electrican will bring in a 320a and not explain things the way Bob did which will make the homeowner think you don't know what you're talking about.

Explain to the owner the amperage categories like Bob did. . Don't pass control to another contractor that can make you look like a fool.

David
 
tallgirl said:
Personal preference.

My father swears by OSB, I think it stinks. Some people like engineered beams, I don't much care for them. For one thing, I think engineered beams create problems in second story floors, and OSB on decking is more prone to sagging. But that's a completely unprofessional, unscientific opinion I have no intentions of backing up with facts, beyond that an all-wood engineered beam is weaker than a dimensionally identical piece of solid lumber.

I like wood. Giant chunks of wood, not pieced or glued or stapled or anything else of the sort. Except plywood, but that's kinda unavoidable ...
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Okay I agree about OSB and I hate particle board...except for certain applications where cost savings or its ability to sag become an advantage. But as far as an all wood engineered beam being weaker than a piece of solid lumber... even if it were really true... the consistent quality and cost savings always outweigh it. As far as problems with second story floors what do you call it when a solid wood beam warps, twists, or splits? I'm curious what kind of problems you've seen with them.

Oh and by the way are congratulations in order on becoming an apprentice? :D
 
bencelest said:
Well actually I have not figure out to devide the load in half yet. Remember I asked the question if I could drill a hole to the main beam? The main beam is located right in the middle of the 1st floor of the house. I find out that I can get away from drillingthe main beam .
if I can route the feed wire to the submain at the attic of the 2nd floor and down the wine room on the other side of the main beam. But the jacuzzi, kitchen appliances and the heavy loads are located in this area and I can't put much load to the main service wiithout using much longer wires. This house is shaped like a U and the main sevice panel will be located at the tip of th U.
I got the OK from the PoCo to install a 200 amp service when I told them that the water heater, stove, central heat and dryer will be gas.
With the new code that says this and that will be dedicated, I am afraid that I may run out of space to put the circuit breakers so I was looking for a submain that would carry the max of breakers for a hundred amp submain.

I use a 200 a 40 circuit sub panel and then feed it with what ever size feed is needed as long as it is LESS THEN the 200a max and the ocp is sized correctly for the feeder. It is much easier to work in a large panel then a small one. I also feel the over sized bussing will last longer because it is larger and able to shed any heat build up faster then a smaller panel could.
As far as the main beam issue we drill them all the time. If I remember you said this beam is 6"x14" x16ft is it a paralamb or gluelamb? I would doubt it is not an engeneered beam unless it is exposed , that would be a pricey beam.If it is a laminated beam 'IMO' you could put a 2'' hole horizontally in the center and it would not be an issue. this is common for us and the engeneers never have a problem with it. Look at what the plumber does to them and you will see my point.4'' cast iron drain in the middle of a paralamb
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DaveTap said:
Okay I agree about OSB and I hate particle board...except for certain applications where cost savings or its ability to sag become an advantage.
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Oy. I don't know that sagging particleboard is ever an advantage unless it's reinforced or protected against catestrophic failure.

But as far as an all wood engineered beam being weaker than a piece of solid lumber... even if it were really true... the consistent quality and cost savings always outweigh it. As far as problems with second story floors what do you call it when a solid wood beam warps, twists, or splits? I'm curious what kind of problems you've seen with them.
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It is really true, though you've got a valid point about consistent quality. That's about the only thing I can say good about OSB and engineered lumber.

What do I call it when a second floor joist goes south? A big ugly mess? Still, I think the potential for a piece of wood that's got a flange 2 or 3" deep, and that's it, to have problems is greater over the long haul than a piece of wood that's wood from top to bottom. Working in old houses, and especially really old houses, I've gained a lot of respect for solid wood. I've been in houses that were under 15 feet of water for weeks on end and once we gut the innards and killl the mold, they're ready to start their way back to being houses. I'd like to see OSB or engineered lumber do that.

Oh and by the way are congratulations in order on becoming an apprentice? :D
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Heh. I'm still waiting to hear from my father about my hair-brained idea to restart his GC business. Things could be really interesting as we (obviously) live in different states and I want to own the majority of his business if we can get it up and going again. Then I need to contact JATC here in town, then again in New Orleans. Lot's more to do.
 
Dan:
Thanks for very important info regarding the main beam. The beam is manufactured class TJI 360. I got me the specs on that where is the permissible place to cut holes.
And thank you.
I got another dumb question :
If I understand you correctly I can put a 200 amp submain where the combo meter/main is also 200amps? That makes the meter/main just a junction box.

I am still looking for a submain that is bigger than a 100 amps.
 
bencelest said:
Dan:
Thanks for very important info regarding the main beam. The beam is manufactured class TJI 360. I got me the specs on that where is the permissible place to cut holes.
And thank you.
I got another dumb question :
If I understand you correctly I can put a 200 amp submain where the combo meter/main is also 200amps? That makes the meter/main just a junction box.

I am still looking for a submain that is bigger than a 100 amps.
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Try Home Despot (Big Orange). They carry a wide variety of vendor's panels all the way up to "I'm glad that's not my electric bill!" in size.
 
bencelest said:
Where is a good place for the GFI and the emerg shut off for the jacuzzi be if the code says within 5 feet from the edge of the tub? The jacuzzi will be located in the master bedroom.
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I think the code your reading is for hottubs and not just a tub with jets.
 
If I understand you correctly I can put a 200 amp submain where the combo meter/main is also 200amps? That makes the meter/main just a junction box.

I am still looking for a submain that is bigger than a 100 amps.[/QUOTE]


If your using a 200a meter main with distribution, you will have the 200 amp main breaker, and room for branch circuits and feeders.In most 200a meter mains with distribution panels you can use up to 100a or 125a two pole clip-on breakers. that will give you alot of options on how to break up your loads. If it is resonable I try to run my heavey loads out of the main panel such as the oven, air conditioning, hot tub and motor loads.then pull my lighter loads out of the sub panel,usually I put in one 125amp sub panel in a house that size. the smaller circuits comming out of the sub panel such as the kitchen small apliance circuits, the bathroom and general lighting circuits.I would guess if you do this you will have about 20 circuits in the sub panel and 14 in the main panel. 2-Pool, 4-air conditioning,2-oven,2-subfeed, 2-furnace, and what ever rooms are near the main panel.Is this house going to have a fire sprinkler system? They are required in most new houses around here. If yes you will need a circuit for that out of the main.
 
Dan: Thank you so much again for your help. You are giving me valuable pointers to do this job right.
Thanks for your input regarding the panel size, how to route the wires, holes on the main beam , sprinkler system, HE lights and code 24.
Had you not point these things to me ahead of timeI would have had a lot of corrections from the inspector.
And I feel confident talking to the HO about my job!
Thanks again.
 
I am glad to hear that.It is nice to see people that take the time and concern to reserch what they are unsure of to give a quallity end product.I am glad my few minutes of input has been of such value to you.
 
If it is just a 200 amp service couldn`t you use a 200 amp service disconnect and feed a 200 amp mbr feed thru panel to a 200 amp MLO panel downstream.That way you could have 200 amp main ,then a 200 amp mbr feed through(yes you dont need the mbr at the 40 ct panel ) but readily available and legal then feed the mlo panel off the feed through lugs.)After the first disc. all would have to be a 4 wire install but this would eliminate the meter/main high priced situation and allow a 200 amp MLO panel,not a 100 or 125.
 
The reason why I put the meter/main in one end of the U is the architect drew it that way and also the submain. I believe that is the most common way of installing electrical service here. The only time that I see your proposal are on the multidwelling apartments/houses. So far as I can remember I did not see any of that type except on occasional old homes that I trouble shoot.Please remember that I am not in any way object or downgrading your proposal. That will save a lot of wireruns and costs. I am only thinking out loud what would the owner and the architect will say if I alter what is in the plans.

My problem is that the heavy loads such as the jacuzzi, kitchen appliances, stove, AC and such was on the other side of the U. The meter/main is located on the opposite side of U and the main beam is right at center of U. I would like to devide the load in half.

But your proposal will work also if I can find a place almost at the center of U. I still have not though or look about a place for it since the HO decided to get the roof inspection done first before I can start my wiring. I haven't been on the job site for a week now.But will the architect object if I don't follow his drawing? He already wrote down 400 amps service and I am putting a 200 amp already.

There was an add -on that I wired where the architect put down a 400 amp service but I planned to install a 100 amp service. When I asked for a service to disconnect POCO wanted an inspection first. Upon inspection ,they recommend that I installed 200 amps. And that's what I did. And that's why I called the POCO first if they will approve my load calculation.
 
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allenwayne said:
If it is just a 200 amp service couldn`t you use a 200 amp service disconnect and feed a 200 amp mbr feed thru panel to a 200 amp MLO panel downstream.That way you could have 200 amp main ,then a 200 amp mbr feed through(yes you dont need the mbr at the 40 ct panel ) but readily available and legal then feed the mlo panel off the feed through lugs.)After the first disc. all would have to be a 4 wire install but this would eliminate the meter/main high priced situation and allow a 200 amp MLO panel,not a 100 or 125.
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This is a good suggestion if your loads are on the other end of the house from the main and the sub is centrally located in the house.I have used a cutler hammer 200a meter main that has 1-200amp main that feeds a 6 space buss with lugs on the bottom that are feed through rated.You can get afew branch circuits out of it, and still feed a 200 amp sub panel without the need for a second 200amp breaker. I would think other companys make a similar box.The only down side I found to the cuttler hammer panel is it is surface mount only.
 
This is perfect meter main for that house if I can get a few breakers to feed the garage and some guest room and a bathroom. I am going to look for this meter/main. Square D Home Line does not make also semi flush mount only surface mount. This is my choice but no can do.
Thank you guys. I am learning a lot.
 
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