DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   Electrical (http://www.diychatroom.com/f18/)
-   -   i need to know how to calculate how much wire per sq ft to buy (http://www.diychatroom.com/f18/i-need-know-how-calculate-how-much-wire-per-sq-ft-buy-150651/)

ddavis14 07-17-2012 09:52 PM

i need to know how to calculate how much wire per sq ft to buy
 
I am planning to buy a huge home from early 1900's. Without adding the basement and attic the sq ft is about 4700 for both floors together. The lady got an estimate of 9k For a contractor to do it but i want to do it myself. Is there an easy way to go by sq footage on how much materials alone will cost?

andrew79 07-17-2012 10:45 PM

That price is pretty good for a place that size I would think. Until you figure out how you want to do everything then there's no way you can just guess at what it will cost. I've never seen anyone do an estimate without a set of prints to do a take off from.

k_buz 07-17-2012 10:51 PM

Professional electrical contractors argue over pricing new homes by square foot. Without knowing what your home currently has, or a set of prints, there would be no way to even guess.

Keep in mind, when you rewire a house, you need to bring everything up to code...kitchen circuits, laundry circuits, bathroom circuits, GFI's, AFCI's, and tamper-proof receptacles just to name a few. It is not acceptable to simply run new wires to the existing boxes.

ddavis14 07-17-2012 11:05 PM

Thanks for the advice.

joecaption 07-17-2012 11:57 PM

Have you even checked to see if you can pull a permit for this as a home owner?
Going to have to trust me I'm not trying to give you a hard time on your post, it's just I've been doing this stuff for a very long time and have seen way to many people that have been wathing those silly DIY shows and the ones where they buy a house and 2 weeks later make $100,000.
99.9% percent of the time it's just not going to happen.
Take what you think it's going to cost and double up and you will be close.

Speedy Petey 07-18-2012 06:05 AM

Quote:

Originally Posted by ddavis14 (Post 968419)
I am planning to buy a huge home from early 1900's. Without adding the basement and attic the sq ft is about 4700 for both floors together. The lady got an estimate of 9k For a contractor to do it but i want to do it myself. Is there an easy way to go by sq footage on how much materials alone will cost?

IMPOSSIBLE.
IF, and only IF, we had a set of prints showing everything you wanted, you MIGHT be able to get within 20-40% correct. Going simply by sq/ft you might get close for a bare minimum code required job.
It also depends on if you need a service or not.

$9K sounds WAY too cheap IMO. And that HAS to be without a service change/upgrade. The 400A service you'll need will likely be in the $3500 range alone.

AllanJ 07-18-2012 07:19 AM

You may wish to consult with the city inspector about adding new circuits and perhaps putting in a new service while existing circuits remain intact and in use, and also a timeline for when bringing the entire house up to code needs to be completed. (The full answer may depend on how much new work is planned.)

(Note that you may not add on to (extend) an existing non-compliant circuit for example an ungrounded circuit.)

Yoyizit 07-18-2012 05:05 PM

The total wire length req'd probably correlates better to the number and perimeters of the rooms rather than the house sq. footage.

If there are any houses under construction near you, you can see how the wire is routed in the walls. Mostly horizontally, some diagonally, some vertically.

This calc. is tedious but it may be worth it to you to do it.

Jim Port 07-18-2012 05:39 PM

You could install a code minimum or add in all the bells and whistles and the square footage would be the same. Wiring is not like paint, drywall or flooring.

ddawg16 07-18-2012 07:08 PM

If your going to go through all that trouble to rewire.....the cost of the wire is nothing compared to the labor and other materials.

First thing you need to figure out is how many ckts.....I doubt you want to duplicate what is there....otherwise, why bother. Your going to want new lights in new locations...more switches....more outlets.....

Assuming you can do the work yourself (if you were in California, no problem doing it yourself), you will most likely have to bring all of the electrical up to current standards....AFIC for all the bedrooms....wired smoke and CO detectors.....an outlet on each wall....each bathroom with it's own dedicated outlet....all light switches have to have a neutral....etc.

Yea...$9k sounds cheap....almost too cheap for a house that size...I just bougt a 250' roll of 12/2 the other day at HD...$79.....house your size could require anywhere between 5 to 10 rolls like that....depending on what all you do.

You have a lot of homework ahead of you......I would start off by making a dwg of each room and start planning what goes where....

Yoyizit 07-19-2012 02:39 PM

Here's a formula that should correlate well for a one room house where the room is square and has no ceiling fixture.

L = 4 x sqrt(A), where L is the total wire length and A is the room area.
If A = 100 sq. ft, L = 40' of wire. For A=1000 L = 126' and for 2000 it's 179'.

For non-square rooms and multistory houses it gets more complex.


All times are GMT -5. The time now is 07:22 AM.


Copyright 2003-2014 Escalate Media LP. All Rights Reserved