Three way switch

The bathroom is dark. It has one wall light with a pull chain and a "beauty bar" medicine cabinet light activated by (an oddly high) switch next to mirror.  I want to add recessed LED cans, put in a three way switch setup so the lights can be turned on or off next to either door, and add the original wall light to this circuit to maintain the original vibe.

When you have a wall light with a switch on it, that means the switch is inside the light fixture and the wires in the box behind it are always hot. 

This will be our main junction box. The power will come into the box, go out to the switches, come back into the boxed as a "switched hot" and then the switched hot will tie into the old light and the new overhead lights called cans. To show you what I mean, I've drawn you some pictures.

This is how a light works. You allow the electricity to "escape" through the filament to the ground. A voltage is a difference in charge that allows this to happen. The charges want to even out so you allow them to do so by making them do something for you

This is actually closer to how the electricity is routed. It goes in through the bottom tip and out through the threaded sleeve. 

This is a typical interrupter switch. The switch breaks the connection that supplies power to the light. 

This is closer to what it really looks like. Two wires come into the box, white (-)  and black (+).  There is also a ground wire if the wiring is newish. This is essentially a backup ground and won't need to be discussed here.

Here is what I have to start with: a box with wires that supply power, and a light fixture with a pull chain switch built into it.

Now it gets complicated. A three way switch uses 3 conductor wire with two hot wires. The switches don't simply interrupt but rather rout the power to one of two "tracks". If you imagine a train going somewhere with two tracks and two track switches, it would need to have these switches "in agreement" to get to the destination - in our case this is power going to a light.

Here is one configuration: the power come into the first switch box with 14-2, 14 gauge 2 conductor wire. Between the switches is 14-3 wire. From the second switch box, 14-2 goes up to the light. Both switches are either on black or red. The have to be switched to the same hot wire to turn on the light, thus a three way light switch (3 because 2 switches and a light I suppose). 

If you get how the three way works, now for the real challenge - putting this knowledge into use in your preferred configuration.  From earlier: "The power will come into the box, go out to the switches, come back into the boxed as a "switched hot" and then the switched hot will tie into the old light and the new overhead lights called cans." That looks something like this:

See if you can trace the power all the way through. The white wire of the 14-3 becomes the switched hot coming back into our junction box where it feeds the original light and from there some new added cans.

First though I have to turn off the circuit by finding the correct fuse. It's a good idea to write down everything that turns off when you pull this fuse. On a side note, you can think of a fuse like a light bulb that has a thick filament that burns out when too much power is flowing through it (amperage) thus cutting off power to the circuit. 

Pulling the middle left fuse cuts off power to the circuit we want to work on

Here's our wall light. I took out the pull chain because we will have two switches for it. One wire going to the switch from the old light / junction box is the fused hot going to the switch box and coming back through the white wire as the switched hot. The other wire is 14-3 which is going between the 3 way switches. The switched hot connects to the old light and from there to the ceiling lights.

One switch, two switch... red switch blue switch? 

The three way is working! With all the wires it's pretty easy to mix something up. 

After making holes where I want the lights and making more holes to rout the wires, I'm ready to drywall the ceiling. The plaster won't stop falling until you remove it and drywall or drywall over it. Going over this mess is a lot easier than taking it all down and drywalling to the studs... You probably won't miss the 3/4" you would gain from removing all the lath and plaster.

I highly recommend you get a hole saw exactly the size recommended by the instructions of the can you're putting in. It makes retrofit cans go in much easier. This one is 4&1/8" as specified and the can is a nice tight interference fit with the hole

LET THERE BE LIGHT! 

I have one more to put in over the tub but I ran out of the plastic grommets that fit into the metal can box so that the wire going in doesn't have its insulation ripped by the metal edge. (You know how metal boxes have breakouts? The little coin looking things? When you knock those out, you are supposed to put in a connector meant for the type of conduit you are using. Easiest and cheapest for Romex (plastic sheathed conduit) are the plastic click type. They have metal connectors too but they cost more and are harder to install but can be reused.

I am so happy to have that bathroom lit up brightly. Good lighting noticeably improves my mood. I'm still not sure what vanity light I'm going to use for above the mirror but I'm leaning towards a chrome "beauty bar". I think I have one kicking around somewhere. I'm kind of a light fixture hoarder...

Haha actually I have two. 

Asbestos

Old houses can have a lot of asbestos. And this one does! 

Large furnace exhaust duct, about 6 inches in diameter. New ones are so efficient they have an exhaust that is 1.5" PVC. This duct is ASBESTOS cement.

Insulating duct wrap uses ASBESTOS

Different duct wrap. ASBESTOS

Peeking out you can see COPPER ducting. Yes, it was a very different time. 

All the ducts have ASBESTOS insulation that is falling apart which makes dust you can inhale which is the dangerous form.

Original kitchen/laundry floor tile- Very Maybeck! Very ASBESTOS! 

Original toilet flange... 

LEAD! How refreshing

Linoleum flooring has the grey, fibrous qualities of ASBESTOS when it is ripped! Under it is a cement board that appears to be...

ASBESTOS.  

Under that is the original kitchen floor tile, which we are assuming is... ASBESTOS. That's 3 layers of asbestos! Yum!

You may have noticed a pattern. Asbestos was used as an insulator for heating systems. It was also used in floor tiles, especially 9" square tiles, I've heard. Maybeck liked fireproof materials since many of his great works fell victim to fires. Especially after the September 1923 Berkeley hills fire, he began to build most of his creations out of stucco with slate or Spanish tile roofs. But he had even used decorative exterior asbestos tiles, similar to our original kitchen floor, before the '23 fire in his masterpiece First Church of Christ, Scientist in Berkeley.

He gave up on redwood siding and cedar shingle roofs long before the mainstream had given them up, which makes sense since he was very interested in hillside homes which are particularly endangered. Stucco became common in the '20s, but redwood clap board siding was common well into the 60s. Cedar shingles as siding seemed to have a resurgence in the 70s and 80s. Lately cedar shingles are required to have a fireproofing chemical added, making them crazy expensive. As a result, they are used mainly in classy restorations as siding and very rarely as actual roofing. The historic restoration that uses cedar shingles for roofing is only for VERY special buildings since it is much more expensive than composition shingles and doesn't last as long.

Back to asbestos -  

When people hear something is bad, they assume they're gonna need to tent the house and have haz-mat people carefully remove it from their house. It is bad, but not instant-death bad. Similar to how smoking is bad, but one cigarette, or ten a week for that matter, isn't necessarily going to kill you. Remeber that people who get mesothelioma where inhaling the stuff all the time because they had NO IDEA it was bad. So don't freak out - simply put on a mask, disposable jumpsuit and gloves, water it to keep down the dust as much as possible, and put it into heavy duty plastic bags. But don't take my word for it - look it up yourself if you are concerned.

Gas Line and Plumbing Basics

I redid a portion of the gas line today. For those of you unfamiliar with plumbing, originally houses were plumbed with threaded galvanized steel pipe for supply lines, cast iron for drain lines (with hubs), and black threaded steel pipe which is basically the same as the water pipes without the galvanized surface which is a crude rust inhibitor. 

Unfortunately, galvanized steel water pipes get rust buildup and eventually become blocked, especially where they are connected to brass, which is what valves are made of. Valves include the shutoff at the meter, the cold water shutoff at the house, the cold shutoff at the water heater, the angle stops under sinks and toilets, and the hot and cold valves of showers, tubs, and faucets. Meaning after 90 years or so (the original house was built 1927-8), the plumbing is useless, due to an electrolytic reaction between the steel pipes and brass valves. Some particles in water have a charge, and brass and steel have different electrochemical reactions with these particles. Rust, or iron oxidization (iron being the vast majority component of steel) is greatly enhanced at the connection of brass and steel. If you have a house before the '50s, you probably have had to replace all or some of your pipes with copper, which never rusts, can be soldered instead of threaded, and gets along well with brass.

Back to gas lines... 

I have already replaced most of the (supply) plumbing with copper, at great effort and expense (more on this later). I now have a pile of galvanized pipes previously used for water that I have taken out. If the rust is cleaned off, I can use these galvanized threaded pipes in the gas line. I can also reuse pieces of the original gas plumbing which is mostly black steel pipe. Remember: you can use any threaded pipe for gas - black steel, galvanized steel or brass. The gas line is at 1/4 PSI so it doesn't have to hold much pressure - the heavy pipe is so that it doesn't get nailed/screwed/sawed through by accident. If you hit a copper water pipe, it's under much more pressure so you would notice nearly immediately the water spraying everywhere but if you had a copper gas line, you could drill through it and not notice until you had a dangerous amount of gas in the house.

The gas line in the house is as follows: 

+the gas comes up from the ground and goes into the gas meter, which is near the water heater in an unfinished lower level of the house, AKA a "California basement". Most CA craftsman homes have a 6-7' "unfinished lower story" which are often converted into crappy illegal lower units. The legal height for a living space is minimum 7.5'. 

+the gas line goes into/under the house from the meter to the water heater, furnace, and then a very long continuous 1" bent pipe goes up to the upper level additions where the have used wall heaters for the new spaces since central heating ducts traveling that far (50'+) is difficult and impractical unless the furnace is moved to a new, more central location and the gas line and ducting is rerouted.

+the gas pipe coming from the meter is 3/4" which is typical for a SFH (one unit). The pipe going to the WH is 1/2" (typical). The pipe going to the furnace is 3/4" because it is old and inefficient. Newer furnaces use 1/2" gas line and are 95-99% efficient. The one in my house looks to be from the '40s and is likely very inefficient (plus asbestos ducting to boot). The furnace is going to need to be replaced. 

+the 1" gas line going up to the two wall heaters is above spec - 3/4" would be fine. Unlike water pipes, gas expands and contracts readily and a 3/4" gas main doesn't mean 3/4"-pipe-worth-of-flow like it would mean for water. Copper pipes have the flow of the smallest restriction. Gas meters are usually 3/4" and then shortly after can bump up to 1" or more (for industrial applications).

+a high output gas range or medium size gas tankless water heater need 3/4" gas lines. If you have much more than a modern-ish efficient furnace, a standard 40 or 50gal water heater, and a (residential-style) gas range and dryer, you probably should jump up to 1" within a foot of the meter.

I'm redoing the gas line because

-the house originally had an electric range, which is highly unusual for '27 and a classic Maybeck feature. I want a gas range that fits in the 38-39" spot in the kitchen so I can keep it mostly original, so I got an old Wedgewood from the 40s which is around the time of the last permitted additions.

-most old houses have floppy old gas lines that leak and zig zag all over the place and they need to be redone in a tidy, logical way. Also commercial style gas ranges (Wolf, BlueStar, Thermador, Viking etc.) and tankless hot water heaters, both very much in vogue, necessitate a 1" gas line upgrade over 3/4". Be aware of this cost when choosing these appliances as the cost to redo a gas line can be substantial.

Above is the gas going left to the old furnace 3/4", below right going upstairs 1", above right going to water heater and meter

Above is the same basic setup but redone with an added gas line for the Wedgewood range. 

Hard to see but I added a 3/4" line for the range at the upper right corner by the cold shutoff, right next to where it goes out to the meter. 

Old furnac, circa 1940

I capped the gas line headed to the old furnace (top right). The old gas feed is at the top left. I will do the gas line for the furnace when the new one comes. They are substantially smaller and I could move it to the right to make more room to access the "crawl-way" to where the water main comes up under the front deck off the living room.

Note the white ducting - asbestos was used as a great, although poisonous insulator. A natural mineral, it was an additive for duct wrap and used as fireproof asbestos cement ducting and siding (as well as asbestos linoleum floor tiles often in 9" square tiles but you have to test to be sure.)  

3/4" gas line going up

Popping out behind the range  

Every appliance and heater - gas range, oven, dryer, wall furnace, central heat - needs a shutoff valve. 

For the range, you're supposed to have a long hose so you can pull it out from the cabinets, get behind it to shutoff the gas and disconnect the range if you want to change it out. Code says that it would be lame to shutoff the gas at the main just to change an appliance. Imagine no heat or hot water in the winter while your stove is being repaired. It would be sucky.