Main Beam of a Residential House

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bencelest

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Is it permissible to drill holes to the main beam of a house which supports the 2nd floor even though there are other beams that support it?

The second question I have is :
What is the minimum requirement for combination meter/load center for a house 4,200 square feet?
 
I do not know what the building codes say, but from an engineering standpoint a small hole on dead centershould have little effect. If you did an analysis of the beam loading you would find the top of the beam was in compression, the bottom is in tension, and the center is neutral. As the hole gets larger it moves into the top and bottom areas so a large hole is out.
 
Under IRC R502.8.1 and 502.8.2 if it is sawn lumber you have tolerances and if it is Engineered one would have to check the specs.....sorry I do not type fast enough to give you all the allowances. Let me know what type of material it is and I will let you know.
 
bencelest said:
Is it permissible to drill holes to the main beam of a house which supports the 2nd floor even though there are other beams that support it?

The second question I have is :
What is the minimum requirement for combination meter/load center for a house 4,200 square feet?
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You will need to do a load calculation for that answer.Most likely a 200 amp will not handle it.Lot depends on what all is run on gas and other loads like hot tubs.Your lighting load is 3 watts per sq foot for other than garage.So if all this is living space you start with 12.6 kw.

Drilling a beam is something you best ask the arch. and ahj on first.Chances are high they would allow it if you are talking about 1/2 inch
 
bencelest said:
What is the minimum requirement for combination meter/load center for a house 4,200 square feet?
Click to expand...
I just answered one very similar to this on the JLC site. It was for a 4500 square foot home. As I said there, without tons more information, there's no way to answer that. I can get that calc to come out to anywhere from a 100 amp service all the way to slightly over 500 amps. AC? Heat type? Well? water heater type? Pool? Hot Tub? gas/electric kit appliances? blah, blah, blah.
 
bencelest said:
Please where can I know how to calculate "load calculation" ? What book can you suggest for me to buy?
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How about this book:
7005SB.jpg


It's called the National Electrical Code.
 
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.
 
I have never seen a meter socket rated between a 200 and a 400.

You could of course use a 400 socket and install a 225 to 400 amp breaker and appropriate sized conductors.
 
big vic said:
I use 320 amp meter bases all the time
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Vic a 320 class meter socket is a 400 amp meter socket.

100 amp socket = 80 amp continuous 100 amp non-continuous

200 amp socket = 160 amp continuous 200 amp non-continuous

400 amp socket = 320 amp continuous 400 amp non-continuous

600 amp socket = 480 amp continuous 600 amp non-continuous.

All these ratings match perfectly with typical panel board ratings.

100 amp panel = 80 amp continuous 100 amp non-continuous

200 amp panel = 160 amp continuous 200 amp non-continuous

400 amp panel = 320 amp continuous 400 amp non-continuous

600 amp panel = 480 amp continuous 600 amp non-continuous.
 
I would recommend doing a load calc and starting from there. I've seen houses that big take a 200A service.

Chances are, over 200A, you're not going to have much success with a metermain combo service. You're probably going to have to use a meter socket and an outdoor panel nippled together, as suggested. A supply house should have a catalog handy with what they can order in, there may be a 300A metermain available.

Look at the examples in the back of the NEC, for the load calc. Do your best, and bring it here, and we can check your math for you.
 
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