Weekend 10 of Construction and The Big Move

This was one heckuva weekend, with mad buttoning-up of things for travel on Sunday. The doors had been neglected until now as they require extra attention (such as custom door jambs) to install; the French doors were originally fixed glazed doors, and about 18″ too tall for the under-loft area, so they had to be carefully cut down, glued, and clamped, and a jamb made. The bottom sill of the French door jamb was made from scrap white oak, with a carefully-cut slope to it so that all water would drain (you can’t buy 4′ wide sections of metal threshold/sill material at the Big Box Store). It’s one of those niceties we will appreciate although it might not be obvious to the casual observer.

The French doors, modded

The 12v DC wiring did not have a functioning breaker panel to connect to, so the Ebay boat panels were torn apart, sanded clean (’cause they’re old and made of metal, not cheap plastic), and re-assembled with the proper breaker sizes (primarily 5-10 amp). We made a little housing for it so that the rear of the panel can be accessed for maintenance. The breaker switches are also the on/off switches in this case, which works fine. We think it looks steampunk, which is always good!

And in the process, gained great respect for Ace Hardware over other Big Box Stores – we always liked that store over the Big Box, and learned that particular bias from our respective dads. Coincidentally, it seems the place is staffed with DIY dads. Well, another reason why I love them: I called the plumbing and electrical specialty store in town, and after passing me around, found one guy who “kinda” knew 12v – by which he meant, he could discuss LED lighting with you, and recommended I visit the auto electric shop in town to get advice for real 12 volt stuff. I view that as good customer service, nonetheless. But I went to Ace first, just in case, found a great selection of wire for my needs (10-16 AWG, or American Wire Gauge, wire), and the first guy that walked by I posed the same question to: “Do you know anything about 12 volt?” and he answered, “I know all about 12 volt,” as he pulled wire. This surprised me. I asked why, and he said he had previously wired RVs for a living! At this point I freaked out and asked him all the questions I could, since he was the first person I met who knew anything! Here are the highlights:

1. What is the recommended treatment for wire junctions/terminations (i.e. electrical boxes)? Answer: none. You can end the wires in the middle of the wall, just put a couple wire nuts on the bare ends, no box needed.

2. Does it matter if you use larger gauge wire than required for the load or distance? Answer: nope, only a problem with smaller gauge wire than required. It’s just a little more expensive.

3. Where is the best place to get 12v wiring? Answer: auto supply stores often sell rolls of 14, 16, and 18 gauge wire by the 25-50′ for cheaper than by-the-foot wiring. The larger or smaller stuff, get here.

4. Does the color matter for positive and negative? Nope, whatever colors you want. Many people use red and black, but any color will do. Just stick with the same colors so you don’t get confused.

5. Why doesn’t everyone use 12v systems when they are so cool and easy to use?? Answer: The power source has to be close due to losses over distance. Otherwise, no good reason. If you get shocked, “It’s not even bee-sting material.” Fire hazard is low. My note: You do, however, need to use 12v – approved switches rather than regular 120v switches due to the larger amperages, as they can actually melt the terminals of a regular switch if they arc. RV and marine stores sell 12v rocker switches, and the plain ol’ metal toggle switches seem to be used with no problems, either.

So I was stoked. If we ever do anything with the Palomino chassis, I’m doing all 12v DC, just for the fun of it. And maybe I can get my sister involved, too, as it seems 12v DC systems are a great introduction to electrical systems. Would have made my high school physics class WAY more interesting…

12 v panel front

12 v panel back

And we also installed the 120v, 30 amp RV electrical inlet and water inlet, in the newly lined utility closets (for vapor and spark protection). Since we are poor and don’t have our power center or inverter/charger for self-made power yet, but want to be able to plug-and-play later with solar, wind turbines, or generator, we put two gratuitous junction boxes in the utility closet and ran extra conduit through them, so that it will be easy to add those components later without having to try to run more conduit and have a messy cabinet. Messy electrical closets are ugly and bother me.

Electrical cabinet

Water inlet on the propane/water side

Word to the wise: you’d think there’s only one kind of 30 amp RV AC inlet. Wrong. There are two kinds – both have three prongs, but one is a regular plug and the other is a twist-lock variety. Both work, but they are not interchangeable, although they make adapters. The twist-lock variety seems a little more secure, so many of the new 30 amp RV cords have a female locking end and a male non-locking end, like this. Make sure you know what you are getting. I didn’t, and was surprised when I opened the inlet after getting it in the mail. Also, when I talked to Monty Taylor regarding “separable” vs “non-separable” power supply for RV inspection, he said he doesn’t care so long as it’s done well. However, I didn’t think about male vs female receptacles/terminals when I bought one the first go-round. I got a 30a regular 3 prong receptacle (female) for the house. Well, that doesn’t work. You need the plug (male) end installed in the house, so that when you hook up a cable, the male end is free to plug into your power source receptacle and the female end plugs into your house. Can’t have a cord with two male ends, can we? Duh. Good news: if you’re like me and you’re cheap, and you saved the cord from the pop-up camper you ripped apart (those power cords are $50 and up man!) that was permanently attached so one end is a stub with raw wires sticking out, you can buy male and female adapter heads online and at any RV store for less than $20. So that is what I did. I bought an adapter for my twist-lock 30 amp inlet to that we can use either type of plug, and bought a $17 female adapter head with standard RV 30 amp layout to attach to my raw cord. Clear as mud? Yeah, me too. Result is, we are ready for any type of 30 amp power supply! Mwaha!

Next, the utility closet got its cover and doors, and all the window and door openings were covered with plywood for the drive. Hurricane clips were attached from rafters to top plates to secure the roof, and we also added some straps to the front eave, for upward forces while driving.

Boarded up

For the moving day, procure yourself a heavy-duty truck to do the pulling, and a good, optimistic friend or family member to drive behind you and call periodically to tell you nothing has fallen off. And as Dee Williams says in her e-book, to also tell you, “It’s so cu-ute!” and soothe your nerves. In our case, have the calm ones in the big truck, and the documenters following behind (only if not driving, of course) and providing caravan-afforded protection from tailgaters and other silly people.

Over the mountains

For those who look at our house and say “It’s so tall! Are you sure the wind won’t blow it over?” the answer is that it did great on the road. We had no concerns driving it whatsoever, and in fact it surprised all of us, in a very welcome way. The only thing that wobbled was the license plate, because it’s attached by a flimsy plastic bracket on the top only, which we can handle. Nothing flew off, nothing was broken. Sigh.

We do recommend using a truck weigh station to find out how much your trailer weighs, while you’re on the road anyway. You don’t have to pay, it isn’t hard, and the scales are always on, even if the station is closed. We found out, after much panicked calculations, that our house weighs about 800 more than we had projected, at 7,300 lbs. For those contemplating a rounded roof such as ours, do keep in mind that you will have considerably more wall height, and therefore weight, compared to a typical Tumbleweed gabled house. We did not consider that in our calculations. Oops. We are now left with less weight to work with in finishing, but with care we will still come in under our weight limit. If you look up Colin’s Coastal Cabin on The Tiny House Blog, he has a shed roof but similar high walls, and he came in at 9,000 lbs. His house is gorgeous and well-made. So be aware of weight! It adds up in a sneaky sort of way.

Now, getting our tiny house onto our narrow lot from our narrow lane with a large truck and rented power mover, that was a long story, to be discussed at a later date. The happy ending is: our house is now resting comfortably on our lot, with jacks to stabilize, and many neighbors already stopping by to ask questions, only 10 minutes away now instead of hours. About three weeks left until we move in!

On the road

Weekend 2: Subfloor finished!

This weekend was much better for working outside in, as it was a little breezy, and sunny but not beating down. Metal flashing with sun on it is fairly blinding.

Subfloor in progress

Bought the 3/8″ plywood and laid it down, feeling much better about that than only flashing. Finished boxing in the 5 compartments of the trailer, making sure that we “boxed in” the spots for all of our plumbing drains (in our case, the tub and the two sinks, as we will be treating greywater on site for irrigation). No toilet drain needed, as we are going the humanure route (I’ll post pictures of our potty at a later date). We also ran 5/8″ all-thread through the outside stringer in the main compartment, and through both boards in the fender compartments, bolting everything together securely. Another nice feature of the Iron Eagle trailer is that they ask you where you want your bolt holes, and weld washers in place on either side of the box beam so that it is powder coated with the rest of the trailer. That way there is no damage to the finish, and nothing can rust!

A side note: if the ceiling under your loft is only 6’2″-6’4″ as most are, did you think about how your tub drain sticks out? Don’t want to hit your head on the ceiling because you forgot to account for that stupid drain outlet when plumbing in. Of course our tub drain landed exactly on a floor joist, so we had to cut it and box the area in, but better realizing it now than later…

Once the drains were boxed in, the floor screwed together and bolted to the frame, it was time to “sheep and sheet” as we said! The wool smelled like clean sheep, and no gloves, respirator or goggles are required; even the kiddies helped “fluff fluff” the insulation:

Wool insulation

The whole family helped with the insulation!

 

 

 

 

 

 

 

 

 

 

 

As we insulated each compartment we sheeted over everything with 3/4″ thick subfloor plywood, which is expensive but really the best; PAD and Tumbleweed agree on this. I thought maybe 1/2″ thick flooring would be fine, to save on height, but everyone says you’ll feel the floor sag if you do anything less. So shell out for the 3/4″ sheathing!

We were frustrated at first that it took us two whole weekends to do the subflooring, but many tiny housers say it took them more time too, so we are trying not to panic. Since we are doing a curved roof that will probably also slow us down a little as well. But she sure does look good, all fleshed out with no more ribs showing!

The finished subfloor

 

 

Weekend 1: Subfloor Underlayment and Sealing

So we hauled the trailer over the mountains with much trepidation, and arrived without a problem. The trailer actually tows very well. Everyone who sees her says she’s beautiful! Here was the view welcoming us:

First step, laying the subfloor. Since we have fancy extendo-crossmembers we actually have to frame in 5 boxes, two on either side of the fenders plus the main area. Which brings us to the first conundrum: what type of underlayment do we want? It needs to be strong enough to handle the errant stick, keep out moisture, rodents, and other would-be residents, and protect the floor insulation.

Tumbleweed recommends aluminum flashing nailed to pressure treated lumber stringers laid on their flat side, framing, followed by extruded polystyrene foam with expanding foam insulation to fill in the cracks. Nasty chemicals, the whole lot, and would definitely off-gas! And we discovered that to use aluminum flashing would cost $200. Ouch.

PAD recommends marine grade coated waterproof 1/4″ plywood, followed by wool insulation (treated with only borax). We really like the wool idea (especially since it is grown in Oregon, and sold in Ranier!), but coated marine grade plywood is, again, nasty stuff. In general, adhesives and sealants are the hidden bugaboos for MCS-ers trying to build a house, and marine-grade plywood fails on both counts, although it is thin, lightweight, and waterproof. Traditional construction adhesives all typically use solvents that off-gas, at minimum, a lot of formaldehyde. Now, the pig-headed construction orthodoxy will argue that natural wood off-gasses formaldehyde too, and technically they are correct, so if you see a wood product that says “No VOCs”, they are lying. However, the RATE and AMOUNT is so tiny as to be almost unmeasurable, so as close to natural wood as possible is the way to go.

So about plywood. Interior grade plywood often uses urea-formaldehyde adhesive, which is the worst of the adhesives; ironically the very stuff you would have closest to you, breathing in the goodness. No surprise, as once again, most construction adhesives are derived from fossil fuels. Exterior grade plywood typically uses phenol-formaldehyde, which still off-gasses, but at a much lower rate. You can find interior plywood at greater cost that is urea-formaldehyde-free (meaning they use phenol-formaldehyde), but you cannot find a lo-VOC exterior grade plywood. At least we couldn’t. OSB (oriented strand board) is, along with particleboard, the nastiest of all the plywoods, heaviest, and turns to oatmeal when wet, so no OSB anywhere in our house. It’s only benefit in construction is that it is a little cheaper.

So we went for the least of evils:

Galvanized steel flashing, which cost half as much as the aluminum, a 3/8″ thick sheet of CDX (a type of exterior grade) plywood on top of that, followed by our stringers of 2×6″ pine. To seal the cracks in the flashing, we used a type of adhesive flashing tape… joy! Back to the computer, looked it up, and there are two large groups of flashing tapes, those made with asphalt and those made with butyl rubber. Apparently the latter is not good, but not terrible as it does not off-gas any VOCs unlike asphalt tape. Here’s the article for your interest: http://www.bestmaterials.com/PDF_Files/flashing-tapes-manual.pdf

Main compartment flashed and taped

And for your information, metal flashing is a pain in the butt to get tight enough if you are just screwing it straight into your cross-members, which is probably why Jay used the stringers as he did. We found out the hard way that it leaves lots of gaps around the edges, and a lot of gaps in the middle if it is not perfectly tight, which is fine if you’re using polystyrene board, which no creature is terribly interested in. So we added the 3/8″ plywood the weekend after, as we thought it would be better able to protect the wool insulation, and likely why PAD used a solid wood underlayment. Next week: finish the subfloor!

Choosing Your Trailer

Our trailer from Iron Eagle Trailers

There are as many trailer types as there are types of people. The questions we wrestled with:

Do you want a house on wheels, or just the freedom from debt, and the ability to live and build tiny as you like?

In other words,  are you better off building a <120 square foot house to lower costs and avoid building permits? The International Building Code (which is really a misnomer – it’s used pretty much only in the US and Canada) specifies that permanent structures under 120 square feet and 11′ average roof height do not require a building permit, thereby fulfilling most of the goals of tiny housers except mobility. If a tiny permanent house is really what you want, but you didn’t know you could do that, I recommend you read The Hand-Sculpted House by Ianto Evans about cob house construction. Don’t know what cob is? Then you definitely need to look into it. Oregon cob is awesome, and a true green building material!

Length – most tiny houses that are lived in full time are between 16 and 20 ft long (trailers are measured by deck size, not total length, so a 20′ trailer may actually be 24′ feet long). Maximum road size for a trailer with a fixed load, such as a tiny house, is 13’6″ high from road to rooftop, and 8’6″ from side to side without needing special licensing or permits. I believe this is all states, but check into it.

Axles – how many, what type, and how much weight will they carry? Single axle trailers are for the super-light-living tiny housers, or for vacation teardrops or tinies such as this one. The axles are generally rated for somewhere between 3,500 or 5,000 lbs GVW, or gross vehicular weight. This means that the weight of the trailer must also be counted when you are figuring the weight of your house carried by the axles. The weight rating depends on a few things, such as the thickness and shape of the axle, and can often be told by the lug pattern on the wheels – 5 lugs usually means 3,500 lbs and 6 lugs 5,000, but the safest way to find out is to look on the axle itself for a label or a stamp with the mfr info.  You also want to know what kind of suspension the axles have – traditional steel leaf springs, or Torq-type axles, which contain rubber and will age and crack as all rubber does, but bounce better while they last. I don’t know of any commercial trailers I looked at that had Torq axles, so probably not something to worry about. There are also drop axles, which generally allow the deck to be lowered by 4″, but interfere with maximizing the space between wheel wells, and give you less clearance under your house but more height to work with.

Style – There are flatbed utility trailers that have the deck mounted between the wheel wells, or over them, some with dove tails on the back. There are also used RV trailers that have had the upper parts removed that you can sometimes find or salvage, or custom trailers made just for tiny houses!

Flatbed utility –  If you get the utility type mounted between wheel wells, you either have to contend with framing in the wells that stick out from your walls internally, or having a house that is very narrow built between the wells, but you get more head room for a loft if you want it (remember, 13’6″ for road height).

Over-the-wheels decked trailers – The over-the-wheels flatbeds are easier to frame in and nice and wide, but you lose a ton of head room so you might have to compensate by having a longer trailer. More air movement under the house could also cause excessive cooling if you live in a cool climate, but might be good for a hot one.

Dovetailed trailers are a pain, but you can use them if you’ve got the patience and time to frame them.

Used RV frames might work, but they are often heavily rusted and you would have to check out the condition of the axles/wheels and the weight rating. They don’t always have heavy duty axles suitable for a heavy tiny house. Interested in salvaging an old RV for a trailer? See Zyl’s post on the tinyhouseblog: http://tinyhouseblog.com/tiny-house-concept/recycling-old-rv-trailers/. He gave a really realistic table of the costs and benefits.

Custom tiny house trailer – Awesome. We originally bought a regular 10k 18′ utility trailer, but after reading Go House Go and visiting all the people we could living in tiny houses, we decided the drop deck style with extended cross members was the best idea. That way, you get the benefits of the over-the-wheels deck stability with the preserved head room of the typical flatbed.

Other Essentials:

– Electric lights, electric brakes, and an emergency breakaway kit. Just because it has electric lights does not mean it has electric brakes. The emergency breakaway kit is a tiny battery with a mechanism that is wired into your existing axle brakes. The mechanism has a cable which you attach to your vehicle just like the chains. If your dear little house should ever come unhitched while being towed, come unplugged, and the chains break, it will trip the little mechanism when the cable is pulled, and engage your trailer’s brakes for you, so you don’t have a runaway tiny house going too far. Really important, don’t you think? You can buy the kits online, or if you are lucky enough to have a trailer company that specializes in tiny house or heavy trailers, they might come stock or install it for you.

–Look for quality. Do the welds look like crap? Don’t buy it. How about the electrical system? Does the electrical harness look sketchy? Does it work? Is the trailer frame made out of I beam, C channel, or box beams? (in order of quality and strength). How far apart are the cross-members? Fewer is better for keeping the trailer light, but closer together is better if you want to carry more weight. Usually you want them no farther than 24″ apart, but 16″ o.c. is overkill. Is the electrical system safely tucked into the trailer frame, or is it flopping around to get torn loose and run over? Do the tires look worn or old? Is it rusted? If it is, is it surface rust you can remove and paint over, or do you have structural damage? Does it have a warranty so if you have problems you can get help? Does it have a grease system that is easy to use so you’ll maintain your axle bearings properly? Also, is it registered? Is the title clear of problems (e.g. is the current seller’s name the last one listed on the title? If not, be afraid!)

What You Don’t Need:

– Railings of any kind above the decking, “sticker pockets”, ramps, or full decking (you may save some of the boards to use in your subfloor and bottom plates if you don’t mind the horrific chemicals in pressure treated wood, or if you were lucky enough to get a cedar deck)

For reference, our trailer is a dual axle HD 10k, which means each axle can carry 5,000 lbs, for a total of 10,000 lbs weight. In Oregon, anything over 8,000 lbs is considered a “heavy trailer” and must be registered as such. The trailer guy we bought ours from said over 10,000 lbs you need a special permit – I don’t know if that is for all states or just Oregon, so check with your Dept of Motor Vehicles. Our trailer itself weighs around 1,430 lbs, which leaves us with around 8,570 lbs of house/stuff weight to work with. It came with an emergency breakaway kit, squared off wheel wells for easier framing, maximized space between the wells and a maxed-out road width of 8’6″. The best part for us is that the cross-members, or the welded joists between the framing, are actually welded below the frame, so that we can have a nice insulated floor that is 6″ thick without losing all the head room, and the cross members extend out flush with the wheel wells, so our walls are weight bearing on steel, not the suspended subfloor built on top of the trailer frame like in the Tumbleweed designs.

A word about cost:

DO NOT SCRIMP ON YOUR TRAILER. Really. We are not made of money either, so believe us. We bought as much as we could secondhand, but the trailer is where you should splurge, and it should be the biggest expenditure you make on your tiny house. If you buy a crummy trailer, you will worry about your house forevermore, especially when moving it, even more so if you don’t/can’t get insurance on it. Save up and buy the best trailer you can. You can always upgrade your appliances or your furniture or even your windows but you can do little to improve your trailer once it is built. We were stupid, and learned the hard way. Learn from us. We really liked Iron Eagle Trailers, if you want a place to start, as they do really high quality work and they went the extra mile for us. The cost was worth every dime.

Hope this helps you as you ponder buying new or purchasing that Craigslist gem!