Wall Enclosure Questions

[panhandle]

I'm new here, and I didn't want to hijack one of the other wall enclosure threads. I'm not at a point in my life to build a house right now, but I will be in a few years, and I have some down time now so I'm trying to get the concepts down and then get rough plans drawn in the next few months.

I'm interested in vertical t&g interior walls, and vertical board and batten exterior walls. This means horizontal nailers. If one of my bays is 14ft, for example, wouldn't I also need vertical supports for the walls between the bents? Horizontal nailers alone, spanning 14 feet, would allow for some serious flex in the walls, unless I used 2x12 nailers or something equally ridiculous.

Accordingly, I'm looking for an explanation, and perhaps some drawings, of an enclosure system that allows for vertical boards on both interior and exterior. I'm also keen on hearing how to minimize lumber use in a wrap and strap enclosure system.

Thanks in advance.

[Rooster]

PN,

Welcome to the Forum.

I wouldn't worry about the load on the nailers/girts since the bottom of your vertical siding will be fastened to some sort of sill plate/beam, and the top of your siding will be fastened to a top-plate or eave purlin. The nailers/girts are more for horizontal wind load  and to help keep a relatively flat wall surface.  When I install new vertical siding, I usually nail the bottom first, and then work my way up the wall.  The "nails to sill" connection can carry the entire load of a 16ft 1x12.  And after they are driven home, it is difficult to then adjust the board up or down without physically hanging on it, or geting a pry-bar involved. 

I am currently working on a wrap and strap project which includes one layer of reclaimed vertical siding nailed to the outside of the frame to allow the full frame to be exposed on the inside, stacked layers of EPS foam board, full 1x4 straps secured through the foam and to the inside nailers/girts/ horizontal beams, and then new rough sawn 1x12 vertical siding nailed to the strapping.  I will be starting a new thread in the near future which will highlight this process and other unique aspect of the build.

Rooster

[Thehardway]

Panhandle,

Welcome,

I assume if this project is in northern Idaho it will need to be well insulated.  There are many things to consider when choosing an enclosure system.  You have stated what you want as the bread for your enclosure sandwich but more important is the meat that goes in between.  This could be a variety of things.  Here are a few options beginning with the common and moving to the less common;  Horizontal nailers, 2x4 or 2x6 conventional framing infill with insulation, SIP's, ecoblock, ICF, cordwood, AAC block, strawbale, wattle and daub, layered wood, timbers, etc.

All of these can be made to perform well.  Cost depends largely on availability of materials, labor costs and time available for completion.  They all have pros and cons and some lend themselves better to DIY than others. Just about all of these could have the interior/exterior finishes you described attached.

Some people like to keep things authentic and some are more concerned with performance.

"Wrap and strap" as we call it likely falls somewhere in the middle of the spectrum using both authentic (wood B&B) materials and modern (foam) materials.  It's performance depends largely on how tight the installer makes his joints and whether or not the assembly is sealed well.  It is all in the skill of the installer.

Better advisement can be given if you can tell us a few things about the location, use, and proposed sources of heating and cooling.

A very tight house does not lend itself well to use of wood burning fireplaces/stoves as they require a significant amount of makeup air for combustion.  Conversely, a house that naturally breathes well would not be a good candidate for an air/air heat pump or electric heat.

If built properly, homes should require very little energy use for heating/cooling purposes.  Will your house have many windows and on what exposure will they be?  Will there be any large thermal storage type items such as masonry floors, walls or fireplaces that will absorb solar radiation and re-radiate it in the house?  All these things should be considered when you design your home and the enclosure system for it. 

My theory is that if your home is well thought out and properly designed and built,  it will provide shelter and warmth to you at no cost the rest of your life at no cost.  If it is not well thought out, and is poorly designed and built, you will be providing shelter and warmth to your home the rest of your life at a very high cost. 

Some peoples home work for them, other people work for their homes.

Consider things like geo/solar orientation, thermal mass, seasonal shading, thermal bridging, radiant heating, reflective roofing, and convection when you plan your enclosure system. 

Give us some more details and we can likely give you some more ideas.  You have found some of the most resourceful sites and some of the best people to encourage and advise which will serve you well on your journey.

[panhandle]

Thanks, hardway and Rooster, for the responses.

My plan is to build a small simple rectangle: one story (~600ft2) plus a loft. It will be my primary residence. I will need wire and pipe chases in at least some of the walls for electricity and water. I will heat with a wood burning stove. I don't need an active cooling system. I want a well insulated house, but I don't need screaming R-values, as a house that small will be relatively easy to heat. On the other hand, though I have land with plenty of wood, I'd rather not burn huge cordage each winter. One of my biggest concerns is indoor air quality, and I know nothing about HVAC systems to keep air moving. I also know that a wood stove is terrible for indoor air quality, but I am content to burn wood anyway. I would like to use as much natural material as possible in the walls to help with indoor air quality.

I'm attracted to wrap and strap because if I did the labor myself it would be significantly cheaper than SIPs. I also am asthetically attracted to t&g interior and b&b exterior. I can cut the boards and battens and make t&g boards myself, which further saves on costs. But I don't like the idea of using a lot of lumber to basically build a stick frame outside the timber frame. I am open to other enclosure systems, but I am quite sure I want an all-wood interior.

I recognize that I am dealing with a huge resource at this forum, and I really appreciate the openness and warmth here. Thanks!

[logman]

I used sips on both timber frames I've built for my wife and I.  I'm heating with my propane hot water heater and baseboard heat.  I am planning on getting an outdoor wood boiler to use as my primary heat source and using my water heater as a backup in case we go away or whatever.  I wasn't sure what temp my water heater would get to until I got it all hooked up since it just has warm, hot and very hot on the control.  It is putting out 145 degree water temp. which I wasn't sure how well that was going to work.  So far this winter, which has been mild except for a couple real cold days it is working great.  We keep our t-stats on 72 and it maintains that with no problem.  We also have 2 gas fireplaces.  I'm heating about 1400 sq. ft.  I don't know how well wrap and strap would have done.  I did see which would have been cheaper and sips were just a little more and went up faster than wrap and strap would have.  We also have t&g on our walls and b&b on the outside.  I get my sips from General Panel out of Tn.  I put up a little timber frame for a client a few years ago in Mt. and it was cheaper to get sips from Tn shipped to Mt. than any of the quotes from sip companies closer to Mt. 

[losttheplot]

One of my biggest concerns is indoor air quality, and I know nothing about HVAC systems to keep air moving. I also know that a wood stove is terrible for indoor air quality, but I am content to burn wood anyway. I would like to use as much natural material as possible in the walls to help with indoor air quality.

I am not sure what makes you think a wood stove is terrible for indoor air quality.
The stove is "air tight" and draws its combustion air from outside. If your stove is working correctly there will be no smoke in the house.

I have a 900sqft house that is conventional stick framed, we heat with a wood stove.
It is insulated with pink fiberglass and has lots of windows.
Our average temperature in January is 2.3* Celsius.

I live on the north side of a hill, we have no direct sun for 3 months a year.  :(
Most evenings we have the stove dampened down and have to open a window to cool things off.
A loft in a 600ft building would benefit from a couple of windows for cross ventilation.

One thing that would have the biggest impact on your plans is the local building regulations and how the inspector interprets them.
It would seem the building regulations are more aimed at sustaining the economy than improving building longevity.
I hope your not restricted by them.

There is a lot of information, on the web, for people who want to have a small home.
It is surprising how quickly floor space gets used up for the basic necessities.
I spent a long time sketching floor plans before I cut any wood.

I found the forum at country plans very helpful. It is filled with people living in / building small homes.

Good for you for not being a slave to a big expensive house.




 

Sometimes it snows  :(

[panhandle]

Thanks losttheplot!

I grew up in an house that was heated with an old wood stove, which leaked particulate-laden air like crazy. To my delight, it seems things have changed.

There are no building inspections where I'm headed, so I'll be free to build as I see fit. It's a very libertarian area.

[Thehardway]

Panhandle,

Here is my opinion and I know it isn't worth much but it makes me feel good to give it.

An outdoor woodfired boiler is a great option.  It gives you the ability to burn your waste wood and heat your home and an unlimited supply of hot water without having to haul dirty wood into the home and deal with smoke, particulate laden air, how to supply makeup air for combustion and the possiblity of having a house fire from embers, forgotten dampers, chimney fires and the likes.

It also gives you the ability to better place the heat where you want it by use of radiant baseboard heaters.  You can pipe the heat to the rooms where you want it and simply turn it off if it gets to warm by means of a valve.  you can't do this with a wood stove unless you run a lot of expensive duct work and take up a lot of useable space.

They can be shut down tightly so you get a longer burn time and also handle larger loads and lengths.  I know guys that can get 2 days out of a single loading.  They can be set up with automatic feeds for backup fuel in case you need to go out of town you won't come back to a cold house and busted water pipes.

As for wrap and strap with B&B siding and vertical boards inside.  Keep in mind that you will have lots of joints between boards and foam that need to be sealed up somehow.  Spray foam can do this but it gets messy. If using natural fibers or fiberglass infil, anywhere, make sure you allow it to breathe and don't seal both sides with a vapor barrier.

You can use an HRV for changing air in the house if needed.  If you enjoy sitting around a indoor woodstove and don't mind it getting really warm upstairs, an HRV isn't a bad way to go.

Personally I like to design with thermal mass.  For a house your size I would probably do a log infill between posts kind of peice-en-peice style with B& batt over the exterior.  This would give you a natural wood log interior and a low maintenance exterior. It would perform quite well thermally due to its mass and would not require time consuming corner notching like a conventional log cabin. 

My house is a 24X32 footprint with a 16X 15 loft.  It is ICF walls with timberframe and sip roof using radiant concrete/tile floors.  We are in a moderate climate here in VA but it requires virtually no heat in the winter and very little cooling in the summer due to the large thermal mass.