ARE DOMES DEAD?
==========
(Posted to cheap-shelters 5/04.)
==========
MVS: "after Domebook 3 they realized that domes are not the one size fits all cure for awful architectural standards, and really don't work very well for the way most of us actually
live."
==========
I must confess to an early fixation on the potential economies of the dome shape. But -- like most things in life -- there is the way things could be/should be and there is the way things ARE. Since then, even as a carpenter, I've been unable to justify all the intricate compound angles and material waste and inefficient labor to end up with something most of my neighbors are going to HATE anyway. A multi-faceted shape -- like the pallet quonset or the pallet gothic arch -- with a square footrprint, like 16x16 is MUCH simpler and cheaper to build and retains many of the economies of heating and cooling which were an early promise of the dome AND has 27% more floor space than a 16' diameter dome. Plus the end result -- especially with the gothic arch shape -- is more conventional and attracts less of that special attention from the powers that be. It also results in two nice vertical endwalls for easy (conventional) installation of doors and windows.
==========
For those die-hards committed to "living in the round" no matter what, there is a multi-faceted approach to building a "dome" which results in each facet being a four-sided trapezoidal instead of a three-sided triangle. This approach cuts waste of materials to an acceptable minimum.
==========
The author of "Home Work" recounts the illustrious history of the dome. His arduous conclusion at some point that "domes didn't work" must be considered one of the great understatements of all time coming from the primary promoter of them. He goes on to say that if he was trying to build a home these days -- especially if he had to work a JOB at the same time -- it only makes sense to use materials which are readily available and eifficient to work with . . . using methods that are tried and true.
==========
Just as we all have our favorite flavor of ice cream and no one can convince us otherwise, we all have our favorite "flavor" of building shelter. We're quick to advance our flavor's advantages and reluctant to address those ever-present shortcomings. Personally -- for those of us with more time than money -- I think recycling free pallet wood into "conventional" shelter makes good sense and I'm putting a fair amount of time into promoting pallet gothic arch as a real-life test of my bias. I'm also fond of pole barns and LSC (light straw clay) for the economies and ease of construction they represent and I'll incorporate THEM into the design as I'm able. But things change. Six months ago, I knew nothing about LSC. Perhaps six months from now, I'll find something I like better. Until then . . .
==========
Someone once said, "If the only tool in your toolbox is a hammer, every problem starts looking like a nail." I LIKE my hammer, but I want lots of other tools in that box as well. The elusive balance is in enjoying our favorites while acknowledging others have their favorites too -- which are often quite different from ours. Or, better yet, employ a variety of methods and techniques in the same house . . . each wall can be different if we want.
==========
sail4free
==========
Thursday, November 23, 2006
FLOOR OPTIONS -- RADIANT HEAT:
==========
jsmith4973@a... wrote: "This is interesting and appealing. Would it be practical to use larger sleepers and to cover the tubes with a layer of loose sand instead of the concrete? This would make trouble shooting easier, I would think. The sand could be removed with a shop-vac, stored in bags until the leak is located and repaired. Then it could be put back. The OSB or plywood or whatever, could then be put back in place. I always use drywall or deck screws. Makes repair much easier.
==========
LAREN: "Radiant floors, even high in a slab, are very slow to react. There is also very little need for an elaborate heating system in a well insulated house."
==========
I agree that heating requirements for a well insulated house are less and simpler. And because hydronic heating systems are so slow to react, they don't lend themselves to poorly insulated shelter like my mobile home was (and no doubt still is). The furnace rarely shut off otherwise, so we turned the heat down to 55 at night and whenever no one was home. In the morning, I'd flick the thermostat up and the bathroom (right next to the furnace) would be warm in five minutes. Before the house was anywhere near 70, I'd be done with my shower and turn the stat back down to 55 as I rushed out the door. The above scenario is simply not an option with hot water heating systems and it would be incredibly expensive to maintain 70 degrees in that drafty shoe box regardless of the heating system used. (Unless one had a source of FREE hot water as a few lucky -- or rich -- folks do here in the Gem state).
==========
So it's a bit of a paradox: hot water systems (HWS) are only appropriate for well-insulated homes and yet the simplest of heating systems (wood stove) is more than adequate for a well-insulated home (as well as being the heat of choice for residents of poorly-insulated homes who have access to "free" firewood).
==========
I think what makes HWS work for the Habitat home which got this thread started is that it is a four zone system. This allows bedrooms to be heated to even lower levels during the day and allows living and kitchen areas to be heated to lower levels during the night. There is a considerable "flywheel effect" so electronic programmable stats would be required which might start warming an area 2 or 3 hours BEFORE that space would be occupied. On the other hand, these same areas would stop heating -- stop circulating the hot water -- 2 or 3 hours before the use of that space would end. This is usually more efficient than heating all spaces to the same temp 24/7 -- even in a well-insulated home.
==========
Simpler one zone systems = a single $25 thermostat and one $70 circulating pump MIGHT be a heat option for a home with a relatively large central kitchen/dining/living area which could be allowed to cool headed into the evening and night hours. Vents high and low in adjoining bedrooms (or bedroom doors left open at night) would allow sufficient residual heat to circulate for sleeping. These vents and doors could be closed during the day to conserve and retain heat in the central area. I love wood stoves but it seems they're either cooking us to sleep or freezing us to death and very little in between. Using a woodstove to heat water in a HWS and "charge" the solar pancake under the floor would be a way to spread that SURGE of heat out over a longer time period and heat domestic hot water or at least preheat the water before it goes to the water heater. It might also eliminate the need for those "midnight feedings" of the woodstove.
==========
A sensor near the ceiling on the chimney which allows the circulating pump to run ONLY when chimney temps are above 185 degrees F would make sure that "stealing" heat from the woodstove would not contribute to creosote formation inside the chimney. A "fan control" thermostat could turn the circulating pump ON when air temps vicinity of stove exceed 80 degrees F (or whatever temp setting the owner might choose). When the fire burns down and temps fall below the set level, the circulating pump would turn off and stay off until a new fire was built.
==========
Whether one uses HWS or not, cheap floors -- based on a layer of sand elevated above grade (for above grade shelters at least) -- can be quite nice. Mike Oehler (sp?) writes about laying down black plastic -- secured to wood "form boards" around the perimeter -- and covering the plastic with carpet for a floor our feet were made to walk on . . . they were NOT made to walk on concrete, for example. He says if you get a low spot, pull a corner back and fill it in with more sand or dirt = no big deal. I read about a boat builder who builds a temporary shelter all around any boat he's building. The floor under the boat is simply dirt or gravel -- concealed by wood chips and saw dust in short order -- but at the back end, he has a "shop" where all his tools and equipment are kept. For the shop floor, he lays down plastic and "sleepers" which are 2x4 (redwood or PT would be nice) -- laying flat and loose = NOT on edge and NOT secured to each other. The sleepers are 16" or 24" o/c and he secures (what they call 1" -- actually 3/4") T&G pine for a floor he can sweep clean. As HIS floor is temporary, he uses finish nails to install it -- which makes the eventual DISassembly much easier AND allows the pine boards to be RE-used again and again. A 4" wide layer of cardboard -- or similar -- under the sleepers to keep them from poking holes in the plastic is a good idea.
==========
An indoor "deck" of 2x6 could be installed the same way with the standard pencil gap between deck boards -- although that won't be everyone's cup o' tea. Sheet goods (ply or OSB) could also be installed this way (per jsmith's suggestion) but I'd definitely want a gap around the perimeter of the room so that any moisture which ended up underneath would have a chance to dry out. I think any solid floor deck (like ply or OSB) would tend to insulate and further slow migration of heat from a HWS loop to the living space above the floor. This would lengthen what we call "thermal lag" = the time it takes for the heating source to warm the room to a comfortable level.
==========
I saw one home where they used landscape fabric instead of plastic and there were large plants and small trees growing right in the living areas. Board walks and patio block walks (which adds thermal mass if it is needed) connected various platforms at slightly different elevations where the furniture was and landscape rocks and gravel covered the remaining areas. I love indoor "water fights" so this would be the perfect house for me! Such a "living in a greenhouse" approach would be a natural extension of the earthship approach of allowing sink drains to mainline into indoor planters. (Larger graywater sources like showers and washing machines are usually drained into larger outdoor planters.)
==========
Consider the more conventional expense of floor joists, insulation, ply or OSB deck, underlayment & vinyl -- or pad & carpet -- and IMAGINE what could be done with that same amount of money spent on landscape fabric (or plastic), gravel, decks or platforms floated on sleepers, and a few plantings from Mother Nature's FREE nursery. Water falls, ponds -- a hot tub built right into the ground -- just IMAGINE it! In fact, I think it's a great code-evasion scheme . . . "I'm not building a house; it's a greenhouse!" (And if I choose to watch TV in my greenhouse or eat in there or sleep in there or entertain my friends in there, who is hurt by that?)
==========
A 12x12 or 12x? elevated deck/platform could be wonderful and easy to clean if covered with vinyl (no seams!) or T&G wood of some sort. Pallets are an ideal source of FREE flooring IF one has access to a planer. Store-bought T&G flooring comes in shorter, mixed lengths anyway. The T&G edges (on sides AND ends) can be easily and cleanly made with a router and two simple router bits; a third economical bit would do a nice 1/8" radius "round-over" where the two floor board edges meet. A little sanding and a clear oil finish -- natural and beautiful.
==========
LAREN: "Not one inspector disallowed the system, and none took the time for a tour either."
==========
Isn't that how it goes? Those stuffed shirts are so sure of that which they know nothing about -- combined with no willingness to learn -- because that might require them acknowledging that just maybe they DON'T know everything. Their fragile egos can't afford that reality. Their minds are made up. I don't suppose we should confuse them with any facts. Ignorance is often excusable. No appetite for continuing education is NOT.
==========
LAREN: "If you need to store energy, like from a Solar sunspace, then sand under your floor is a real good heat distribution system. The way you get the heat into it is by blowing air through tubing (4" un-perforated, corrugated plastic septic drain tile tubing) If anyone is interested, I can give further construction details for the "pancake" under floor heat storage."
==========
I can see how that would slow down air flow -- and cause more turbulence -- to maximize transfer of heat between air and sand. I'd like more construction details for the "pancake" system. I was encouraged to read about a similar heat storage system (many years ago -- most likely in MEN) where the original insulated mud slurry "heat storage battery" was allowed to dry out. They discovered the lack of moisture didn't significantly impact on the system's ability to store heat. I was kinda' surprised by that.
==========
sail4free
==========
==========
jsmith4973@a... wrote: "This is interesting and appealing. Would it be practical to use larger sleepers and to cover the tubes with a layer of loose sand instead of the concrete? This would make trouble shooting easier, I would think. The sand could be removed with a shop-vac, stored in bags until the leak is located and repaired. Then it could be put back. The OSB or plywood or whatever, could then be put back in place. I always use drywall or deck screws. Makes repair much easier.
==========
LAREN: "Radiant floors, even high in a slab, are very slow to react. There is also very little need for an elaborate heating system in a well insulated house."
==========
I agree that heating requirements for a well insulated house are less and simpler. And because hydronic heating systems are so slow to react, they don't lend themselves to poorly insulated shelter like my mobile home was (and no doubt still is). The furnace rarely shut off otherwise, so we turned the heat down to 55 at night and whenever no one was home. In the morning, I'd flick the thermostat up and the bathroom (right next to the furnace) would be warm in five minutes. Before the house was anywhere near 70, I'd be done with my shower and turn the stat back down to 55 as I rushed out the door. The above scenario is simply not an option with hot water heating systems and it would be incredibly expensive to maintain 70 degrees in that drafty shoe box regardless of the heating system used. (Unless one had a source of FREE hot water as a few lucky -- or rich -- folks do here in the Gem state).
==========
So it's a bit of a paradox: hot water systems (HWS) are only appropriate for well-insulated homes and yet the simplest of heating systems (wood stove) is more than adequate for a well-insulated home (as well as being the heat of choice for residents of poorly-insulated homes who have access to "free" firewood).
==========
I think what makes HWS work for the Habitat home which got this thread started is that it is a four zone system. This allows bedrooms to be heated to even lower levels during the day and allows living and kitchen areas to be heated to lower levels during the night. There is a considerable "flywheel effect" so electronic programmable stats would be required which might start warming an area 2 or 3 hours BEFORE that space would be occupied. On the other hand, these same areas would stop heating -- stop circulating the hot water -- 2 or 3 hours before the use of that space would end. This is usually more efficient than heating all spaces to the same temp 24/7 -- even in a well-insulated home.
==========
Simpler one zone systems = a single $25 thermostat and one $70 circulating pump MIGHT be a heat option for a home with a relatively large central kitchen/dining/living area which could be allowed to cool headed into the evening and night hours. Vents high and low in adjoining bedrooms (or bedroom doors left open at night) would allow sufficient residual heat to circulate for sleeping. These vents and doors could be closed during the day to conserve and retain heat in the central area. I love wood stoves but it seems they're either cooking us to sleep or freezing us to death and very little in between. Using a woodstove to heat water in a HWS and "charge" the solar pancake under the floor would be a way to spread that SURGE of heat out over a longer time period and heat domestic hot water or at least preheat the water before it goes to the water heater. It might also eliminate the need for those "midnight feedings" of the woodstove.
==========
A sensor near the ceiling on the chimney which allows the circulating pump to run ONLY when chimney temps are above 185 degrees F would make sure that "stealing" heat from the woodstove would not contribute to creosote formation inside the chimney. A "fan control" thermostat could turn the circulating pump ON when air temps vicinity of stove exceed 80 degrees F (or whatever temp setting the owner might choose). When the fire burns down and temps fall below the set level, the circulating pump would turn off and stay off until a new fire was built.
==========
Whether one uses HWS or not, cheap floors -- based on a layer of sand elevated above grade (for above grade shelters at least) -- can be quite nice. Mike Oehler (sp?) writes about laying down black plastic -- secured to wood "form boards" around the perimeter -- and covering the plastic with carpet for a floor our feet were made to walk on . . . they were NOT made to walk on concrete, for example. He says if you get a low spot, pull a corner back and fill it in with more sand or dirt = no big deal. I read about a boat builder who builds a temporary shelter all around any boat he's building. The floor under the boat is simply dirt or gravel -- concealed by wood chips and saw dust in short order -- but at the back end, he has a "shop" where all his tools and equipment are kept. For the shop floor, he lays down plastic and "sleepers" which are 2x4 (redwood or PT would be nice) -- laying flat and loose = NOT on edge and NOT secured to each other. The sleepers are 16" or 24" o/c and he secures (what they call 1" -- actually 3/4") T&G pine for a floor he can sweep clean. As HIS floor is temporary, he uses finish nails to install it -- which makes the eventual DISassembly much easier AND allows the pine boards to be RE-used again and again. A 4" wide layer of cardboard -- or similar -- under the sleepers to keep them from poking holes in the plastic is a good idea.
==========
An indoor "deck" of 2x6 could be installed the same way with the standard pencil gap between deck boards -- although that won't be everyone's cup o' tea. Sheet goods (ply or OSB) could also be installed this way (per jsmith's suggestion) but I'd definitely want a gap around the perimeter of the room so that any moisture which ended up underneath would have a chance to dry out. I think any solid floor deck (like ply or OSB) would tend to insulate and further slow migration of heat from a HWS loop to the living space above the floor. This would lengthen what we call "thermal lag" = the time it takes for the heating source to warm the room to a comfortable level.
==========
I saw one home where they used landscape fabric instead of plastic and there were large plants and small trees growing right in the living areas. Board walks and patio block walks (which adds thermal mass if it is needed) connected various platforms at slightly different elevations where the furniture was and landscape rocks and gravel covered the remaining areas. I love indoor "water fights" so this would be the perfect house for me! Such a "living in a greenhouse" approach would be a natural extension of the earthship approach of allowing sink drains to mainline into indoor planters. (Larger graywater sources like showers and washing machines are usually drained into larger outdoor planters.)
==========
Consider the more conventional expense of floor joists, insulation, ply or OSB deck, underlayment & vinyl -- or pad & carpet -- and IMAGINE what could be done with that same amount of money spent on landscape fabric (or plastic), gravel, decks or platforms floated on sleepers, and a few plantings from Mother Nature's FREE nursery. Water falls, ponds -- a hot tub built right into the ground -- just IMAGINE it! In fact, I think it's a great code-evasion scheme . . . "I'm not building a house; it's a greenhouse!" (And if I choose to watch TV in my greenhouse or eat in there or sleep in there or entertain my friends in there, who is hurt by that?)
==========
A 12x12 or 12x? elevated deck/platform could be wonderful and easy to clean if covered with vinyl (no seams!) or T&G wood of some sort. Pallets are an ideal source of FREE flooring IF one has access to a planer. Store-bought T&G flooring comes in shorter, mixed lengths anyway. The T&G edges (on sides AND ends) can be easily and cleanly made with a router and two simple router bits; a third economical bit would do a nice 1/8" radius "round-over" where the two floor board edges meet. A little sanding and a clear oil finish -- natural and beautiful.
==========
LAREN: "Not one inspector disallowed the system, and none took the time for a tour either."
==========
Isn't that how it goes? Those stuffed shirts are so sure of that which they know nothing about -- combined with no willingness to learn -- because that might require them acknowledging that just maybe they DON'T know everything. Their fragile egos can't afford that reality. Their minds are made up. I don't suppose we should confuse them with any facts. Ignorance is often excusable. No appetite for continuing education is NOT.
==========
LAREN: "If you need to store energy, like from a Solar sunspace, then sand under your floor is a real good heat distribution system. The way you get the heat into it is by blowing air through tubing (4" un-perforated, corrugated plastic septic drain tile tubing) If anyone is interested, I can give further construction details for the "pancake" under floor heat storage."
==========
I can see how that would slow down air flow -- and cause more turbulence -- to maximize transfer of heat between air and sand. I'd like more construction details for the "pancake" system. I was encouraged to read about a similar heat storage system (many years ago -- most likely in MEN) where the original insulated mud slurry "heat storage battery" was allowed to dry out. They discovered the lack of moisture didn't significantly impact on the system's ability to store heat. I was kinda' surprised by that.
==========
sail4free
==========
Sunday, October 23, 2005
BUILDING JIGS TO ASSEMBLE THE RIBS
==========
SASKNELLIE: "For the sake of those of us who are novices, could you post a picture of the jig you used to make the arches?"
==========
There are two "classic" profiles for the gothic arch shape. One uses the full width of the floor as the radius to draw the arc (this makes a taller, narrower-looking shape). The other uses 2/3 of the floor width as the radius (this makes a shorter, wider-looking shape). For ease of reference, I call them "full-width arch" or "2/3-width arch." The 2/3 width arch (in the pictures) has five 3' facets on each side and they all join each other to form a 15 degree angle. This shape is 16' wide and about 10' high. The only exception is at the ridge which is a 45 degree angle. At the ridge, you remove 22-1/2 degrees of wood from the top end of the two pieces which meet each other at the ridge. The lower ends and ALL the other pieces have 7-1/2 degrees of wood removed from BOTH ends. An arch shape can be drawn (and built) using any combination of height and width. This particular one makes a good first choice because the angles are whole numbers and it's a reasonable size for a first effort.
==========
The simplest way to make a jig is to carefully cut and assemble four rib components together with the plywood plates on one side only. Lay 2-1/2 sheets of plywood down to form a shape 8'
wide and 10' tall and fasten them edge to edge with hinges or blocks of wood. In the lower right-hand corner, draw a rectangle 5-1/2" wide and 1-1/2" high -- this will represent your sill plate that the ribs will set on. Position the lower end of your mostly assembled rib on the line -
- just as it will be on top of the 2x6 sill and put a nail or screw (in a pre-drilled hole) close to that lower end so the rib assembly can pivot on that fastener. (This allows you to move
the top end of the rib while the bottom end stays in place.) Next take your fifth rib component (7-1/2 degree on the lower end; 22-1/2 degree on the upper end) and position it so it is touching the top end of the assembled four components AND is flush with the center line extending
down from the ridge (the left edge of your sheets of plywood). Then it's a simple matter of making sure nothing moves and carefully tracing both sides of your rib all the way from the
ridge to the sill plate. Then you can install 2x4 blocks -- two on one side, one on the other of EACH facet and presto -- your jig is done. When assembling the ribs, I start at the ridge and put a screw into that top piece to make sure it holds at the centerline, no matter what. Install all four plates (even the ridge plate can be installed just leaving half of it sticking out in mid-air) and then carefully remove the rib from the jig, flip it over (no jig required for this step) and immediately install the remaining four plates (but NO ridge plate on the second side -- that plate will be attached to the rib coming up from the other side). It's easier to leave the
ribs UNattached at the ridge until immediately prior to standing them up into final
position.
==========
SASKNELLIE: "In my case, not having a chop saw, I would probably make a jig for the cutting as well."
==========
That can work just fine -- use a sharp blade and keep your RPMs up -- go slow and let the saw do the work. Much of your FREE pallet wood will end up with nails embedded in it. I use
chisel-tip blades (go slow to not damage the blades) and swap 'em out as soon as they start
to get dull. It's cheaper to have them re-sharpened than it is to replace good quality blades.
==========
SASKNELLIE: "What angle are you cutting for the full sized version?"
==========
The full-width version has SEVEN 3' facets on each side and is 20' wide and about 17' 6" tall. On this larger model, the ridge angle is 50 degrees so you remove 25 degrees of wood from each
of the two pieces where they meet each other at the ridge. At the other end of those two pieces and BOTH ends of all other pieces, only 5 degrees of wood is removed from BOTH ends. This allows them to join each other and form the necessary 10 degree angles.
==========
SASKNELLIE: "Another question, what will the span be at the level of your loft? I would like to build this in the spring as a garage with lumber storage in the loft area. I'm wondering how much weight this can support before you have to use posts to support from below."
==========
I don't have the drawing in front of me (it's at work) but the span on the loft is considerable -- 14' or so -- too wide to support much of anything without support below it. Were you planning on the solid T&G (Tongue & Groove) 2x6 deck or something more like "collar beams" to store lumber on top of? As a cabin, one would want a wall under the loft to separate the kitchen area from the bath/utility area so making that span manageable with a wall underneath it (splitting the span in half or keeping it at 10' or less) is no problem. Depending on what you want to do, we'll have to get Laren involved to help calculate the anticipated load and what will be required to safely support it. We can only hang so much weight down from the arch ribs. The rest must be supported underneath the loft with either a wall or posts and a beam. So the big question at this point is: solid T&G loft or open framing -- like collar beams? And how long will your loft be -- assuming the width will be "fixed" by the 20' wide gothic arch?
==========
sail4free
==========
==========
SASKNELLIE: "For the sake of those of us who are novices, could you post a picture of the jig you used to make the arches?"
==========
There are two "classic" profiles for the gothic arch shape. One uses the full width of the floor as the radius to draw the arc (this makes a taller, narrower-looking shape). The other uses 2/3 of the floor width as the radius (this makes a shorter, wider-looking shape). For ease of reference, I call them "full-width arch" or "2/3-width arch." The 2/3 width arch (in the pictures) has five 3' facets on each side and they all join each other to form a 15 degree angle. This shape is 16' wide and about 10' high. The only exception is at the ridge which is a 45 degree angle. At the ridge, you remove 22-1/2 degrees of wood from the top end of the two pieces which meet each other at the ridge. The lower ends and ALL the other pieces have 7-1/2 degrees of wood removed from BOTH ends. An arch shape can be drawn (and built) using any combination of height and width. This particular one makes a good first choice because the angles are whole numbers and it's a reasonable size for a first effort.
==========
The simplest way to make a jig is to carefully cut and assemble four rib components together with the plywood plates on one side only. Lay 2-1/2 sheets of plywood down to form a shape 8'
wide and 10' tall and fasten them edge to edge with hinges or blocks of wood. In the lower right-hand corner, draw a rectangle 5-1/2" wide and 1-1/2" high -- this will represent your sill plate that the ribs will set on. Position the lower end of your mostly assembled rib on the line -
- just as it will be on top of the 2x6 sill and put a nail or screw (in a pre-drilled hole) close to that lower end so the rib assembly can pivot on that fastener. (This allows you to move
the top end of the rib while the bottom end stays in place.) Next take your fifth rib component (7-1/2 degree on the lower end; 22-1/2 degree on the upper end) and position it so it is touching the top end of the assembled four components AND is flush with the center line extending
down from the ridge (the left edge of your sheets of plywood). Then it's a simple matter of making sure nothing moves and carefully tracing both sides of your rib all the way from the
ridge to the sill plate. Then you can install 2x4 blocks -- two on one side, one on the other of EACH facet and presto -- your jig is done. When assembling the ribs, I start at the ridge and put a screw into that top piece to make sure it holds at the centerline, no matter what. Install all four plates (even the ridge plate can be installed just leaving half of it sticking out in mid-air) and then carefully remove the rib from the jig, flip it over (no jig required for this step) and immediately install the remaining four plates (but NO ridge plate on the second side -- that plate will be attached to the rib coming up from the other side). It's easier to leave the
ribs UNattached at the ridge until immediately prior to standing them up into final
position.
==========
SASKNELLIE: "In my case, not having a chop saw, I would probably make a jig for the cutting as well."
==========
That can work just fine -- use a sharp blade and keep your RPMs up -- go slow and let the saw do the work. Much of your FREE pallet wood will end up with nails embedded in it. I use
chisel-tip blades (go slow to not damage the blades) and swap 'em out as soon as they start
to get dull. It's cheaper to have them re-sharpened than it is to replace good quality blades.
==========
SASKNELLIE: "What angle are you cutting for the full sized version?"
==========
The full-width version has SEVEN 3' facets on each side and is 20' wide and about 17' 6" tall. On this larger model, the ridge angle is 50 degrees so you remove 25 degrees of wood from each
of the two pieces where they meet each other at the ridge. At the other end of those two pieces and BOTH ends of all other pieces, only 5 degrees of wood is removed from BOTH ends. This allows them to join each other and form the necessary 10 degree angles.
==========
SASKNELLIE: "Another question, what will the span be at the level of your loft? I would like to build this in the spring as a garage with lumber storage in the loft area. I'm wondering how much weight this can support before you have to use posts to support from below."
==========
I don't have the drawing in front of me (it's at work) but the span on the loft is considerable -- 14' or so -- too wide to support much of anything without support below it. Were you planning on the solid T&G (Tongue & Groove) 2x6 deck or something more like "collar beams" to store lumber on top of? As a cabin, one would want a wall under the loft to separate the kitchen area from the bath/utility area so making that span manageable with a wall underneath it (splitting the span in half or keeping it at 10' or less) is no problem. Depending on what you want to do, we'll have to get Laren involved to help calculate the anticipated load and what will be required to safely support it. We can only hang so much weight down from the arch ribs. The rest must be supported underneath the loft with either a wall or posts and a beam. So the big question at this point is: solid T&G loft or open framing -- like collar beams? And how long will your loft be -- assuming the width will be "fixed" by the 20' wide gothic arch?
==========
sail4free
==========
Friday, July 15, 2005
BUILDING MODELS
==========
I like building models of ideas which are more or less to scale. My favorite scale for shelters is 1/4 scale (right?) where 1" in full dimension is only 1/4" for the model. I got a weird start with my pallet gothic arch model and it ended up 36-1/2" wide (representing 16') but it should have been 48" wide and now I kinda' wish it was. My rigid arch facets (representing 3') are only 6" long but would have been 8" long using the 1/4 scale.
==========
These are sizeable models but I'm able to use 1/8" wood paneling scraps for the glue plates where 1/2" plywood is used in real life and I can actually attach the miniature plates with glue and a 1/4" crown air-powered stapler = four staples per plate. I attach my girts and purlins with an 18 gauge air-powered brad nailer (5/8" leg length) and a spot of exterior grade wood glue. If I'm making 1x4s for the model, I rip 1/4" thick strips from a standard 3/4" thick board (2x4s are 1/2" thick). A truer scale would have a 2x4 being 3/8" thick by 7/8" but 1/2" gives a little more "meat" to work with and the standard 3/4" dimension is easier to come by. This scale allows a standard 2x2 (actually 1-1/2" x 1-1/2") to represent a 6x6 post (common for pole barns) and a 3/4" x 3/4" (aka "1x1") to represent a 4x4 post.
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Building models allows one to really see what they're getting themselves into and as you're actually cutting and assembling the individual pieces (much as you'll do building the full-sized one), it's great practice and you'll find a few things will be "worked out" in the model MUCH easier than they would be on the actual building. It's also a great way to show the rest of the world what this thing is that YOU can see so clearly in your head BUT may have a hard time communicating to others -- now you can just show 'em. One of my coworkers was clearly impressed that all my rigid arches lined up so well. He said, "You put all those together on a jig, didn't you?" Well, of course! Only a jig allows things to be consistently "off" and still look good 'cause all the frames are "off" the same -- as long as you never switch 'em end for end, right? Very few things are perfectly symmetrical -- or perfectly plumb and square for that matter -- in the REAL world. It's important to label your frames so you'll always know which side had the glue plates installed first and then just make sure all those "first" sides face the same way. To minimize the variables, I always face my "first" sides towards the front end of the building.
==========
Actually, with the pallet gothic arch I'm recommending the rigid arches be assembled as "ribs" only = NOT joined together at the peak until just prior to standing the rigid arches up into their final position. The ribs can be easily hauled in a pickup with the tailgate down and are much easier to handle this way. As the angle at the peak is different from all the others, the ribs end up lining up whether one labels the "first" side or not -- the right half of the rigid arches will all face the same way and the left half will all face the OTHER way = no worries -- it all works out with no labels necessary.
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sail4free
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I like building models of ideas which are more or less to scale. My favorite scale for shelters is 1/4 scale (right?) where 1" in full dimension is only 1/4" for the model. I got a weird start with my pallet gothic arch model and it ended up 36-1/2" wide (representing 16') but it should have been 48" wide and now I kinda' wish it was. My rigid arch facets (representing 3') are only 6" long but would have been 8" long using the 1/4 scale.
==========
These are sizeable models but I'm able to use 1/8" wood paneling scraps for the glue plates where 1/2" plywood is used in real life and I can actually attach the miniature plates with glue and a 1/4" crown air-powered stapler = four staples per plate. I attach my girts and purlins with an 18 gauge air-powered brad nailer (5/8" leg length) and a spot of exterior grade wood glue. If I'm making 1x4s for the model, I rip 1/4" thick strips from a standard 3/4" thick board (2x4s are 1/2" thick). A truer scale would have a 2x4 being 3/8" thick by 7/8" but 1/2" gives a little more "meat" to work with and the standard 3/4" dimension is easier to come by. This scale allows a standard 2x2 (actually 1-1/2" x 1-1/2") to represent a 6x6 post (common for pole barns) and a 3/4" x 3/4" (aka "1x1") to represent a 4x4 post.
==========
Building models allows one to really see what they're getting themselves into and as you're actually cutting and assembling the individual pieces (much as you'll do building the full-sized one), it's great practice and you'll find a few things will be "worked out" in the model MUCH easier than they would be on the actual building. It's also a great way to show the rest of the world what this thing is that YOU can see so clearly in your head BUT may have a hard time communicating to others -- now you can just show 'em. One of my coworkers was clearly impressed that all my rigid arches lined up so well. He said, "You put all those together on a jig, didn't you?" Well, of course! Only a jig allows things to be consistently "off" and still look good 'cause all the frames are "off" the same -- as long as you never switch 'em end for end, right? Very few things are perfectly symmetrical -- or perfectly plumb and square for that matter -- in the REAL world. It's important to label your frames so you'll always know which side had the glue plates installed first and then just make sure all those "first" sides face the same way. To minimize the variables, I always face my "first" sides towards the front end of the building.
==========
Actually, with the pallet gothic arch I'm recommending the rigid arches be assembled as "ribs" only = NOT joined together at the peak until just prior to standing the rigid arches up into their final position. The ribs can be easily hauled in a pickup with the tailgate down and are much easier to handle this way. As the angle at the peak is different from all the others, the ribs end up lining up whether one labels the "first" side or not -- the right half of the rigid arches will all face the same way and the left half will all face the OTHER way = no worries -- it all works out with no labels necessary.
==========
sail4free
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Monday, July 11, 2005
FLOOR OPTIONS -- DIRT/PLASTIC/CARPET
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Dirt inside can be kept 4 to 6 inches above grade and converted into a floor of some sort. One of my favorites uses redwood 2x4s buried on edge around a room's perimeter. Using these to define "level" the dirt is leveled and compacted in place. A layer of black plastic is put down (stapled to the 2x4s) and then a layer of carpet (preferably used) is stretched over the plastic = instant floor and noone will ever know they're walking on dirt IF you don't tell them. (Thanks to Mike Oehler of "$50 and Up Underground House" for this idea.)
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Another advanatge of the carpet-plastic-dirt floor is it's easy to run new wiring circuits or new plumbing lines -- pull the carpet and plastic back and start digging! When done, backfill and tamp smooth and REinstall the plastic and carpet = no damage, no waste. One can even get "direct-bury" Romex (gray outer sheath) that can be laid all by itself and buried. If rodents are a problem in your area, though, better to fish it inside of plastic pipe to protect it from sharp vermin teeth. Small trees and plants can be planted right IN the floor -- how's THAT for "alternative?"
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sail4free
==========
==========
Dirt inside can be kept 4 to 6 inches above grade and converted into a floor of some sort. One of my favorites uses redwood 2x4s buried on edge around a room's perimeter. Using these to define "level" the dirt is leveled and compacted in place. A layer of black plastic is put down (stapled to the 2x4s) and then a layer of carpet (preferably used) is stretched over the plastic = instant floor and noone will ever know they're walking on dirt IF you don't tell them. (Thanks to Mike Oehler of "$50 and Up Underground House" for this idea.)
==========
Another advanatge of the carpet-plastic-dirt floor is it's easy to run new wiring circuits or new plumbing lines -- pull the carpet and plastic back and start digging! When done, backfill and tamp smooth and REinstall the plastic and carpet = no damage, no waste. One can even get "direct-bury" Romex (gray outer sheath) that can be laid all by itself and buried. If rodents are a problem in your area, though, better to fish it inside of plastic pipe to protect it from sharp vermin teeth. Small trees and plants can be planted right IN the floor -- how's THAT for "alternative?"
==========
sail4free
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Wednesday, October 13, 2004
QUERY ABOUT PALLET GOTHIC ARCHES:
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KAREN: "Please explain further, I know what a gothic arch is but how is one built out of pallets?"
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I get used pallets for free (the ones withOUT the notches cut in the 2x4s for the forklift to approach from the "side"; those are a waste of time for this application) and use my sawzall to clip the nails and take them apart without further damage to the wood. [UPDATE: Since writing this, I've realized there is a good option using the 2x4s with the notches cut in them. It requires some extra work but results in some unexpected benefits too. What we do is pre-drill 2x2s and use 3" screws and construction adhesive to attach them over the edge where the notches are. This results in a 5" deep cavity = more room for insulation AND provides a convenient "hole" for running wiring and plumbing. It also moves the inside edge of the frame inward far enough to clear the glue plates which makes interior finish much easier.] Pallets come in lots of different sizes but I've found the most common size will typically yield three 2x4s about 3' long plus the thinner decking boards -- they're also usually about 3' long. The original challenge was to design something I could build out of 3' long 2x4s. I started out with the quonset idea . . . more info at:http://palletquonset.blogspot.com/
==========
But I live in snow country and the upper two facets on the quonset are too flat to shed snow PLUS I like the look of the gothic arch MUCH better -- quonsets look a little TOO utilitarian -- IMHO. (Yet they have their fans too.) I toyed around with a modification I called the "snow roof" -- basically extending the 2nd layer of facets up to the peak but that required longer 2x4s -- a deviation from the original challenge. So I ended up applying the challenge to a gothic arch shape where the peak is 2/3 of the width of the building -- this allows all floor space to be useable without getting too tall but certainly an arch as tall as the building is wide is also an option (what I call the "full width" pallet gothic arch). I wanted the option of putting a 2/3 width arch on top of a pole-barn type first floor without the whole thing looking way too tall and narrow. Plus the angles on what I'm calling a "2/3 arch" (not knowing what it might technically be called) just seemed right and easy to work with. It is technically a polygonal gothic arch which simply means the surface has multiple facets instead of one smooth curve. On the basic design, the width ends up at 16' and the height at the peak is about 10' -- I didn't want to push my luck with the building gods too far -- some of the pallet lumber can be a little marginal. Length is optional. This results in five angled surfaces (facets) on each side for a total of ten facets for each arch. If one keeps the lower-level ceiling at 7', it's possible to build a loft floor in a portion (or all) of the space for sleeping which only uses up 1-1/2" of vertical space -- leaving more room in the loft and saving the cost of floor joists.
==========
The 3' long FREE 2x4s come together at a 15 degree angle where they are clamped in a temporary jig (constructed on the floor or the ground) and joined on both sides with plywood plates which are glued on with construction adhesive and a narrow crown (7/16") sheathing stapler (air powered). (Using plywood plates like this is common in a building method I've known as "rigid arch" where wall studs and rafters are joined together on the ground and then stood up as a single piece.) Other methods -- like hand nailing -- can be used but the stapler is MUCH faster and arguably stronger. So one piece "ribs" are created -- joined with plates of a different shape at the ridge -- to create a continuous framing piece from the floor up to the peak and back down to the floor. These ribs are placed on 16" centers just like studs and sheathing is attached directly to their outer edges. (24" centers would work also but the 16" centers allow me to use the thinner pallet decking for sheathing as well -- another opportunity for the sheathing stapler to show off AND allow us to use 1/2" sheetrock inside whereas the thicker (and more expensive) 5/8" sheetrock must be used for ceilings under frames on 24" centers.) So it's possible to frame and sheath a shell -- end walls and floor not included -- and then shingle it at VERY low cost. I priced 30-year architectural grade shingles over 30-pound felt (or house wrap) for a 16 X 36 shelter and amortized the cost of those materials over 30 years. The cost worked out to $1.15 per month for 576 square feet (not counting the loft). Now that's what I call cheap shelter!
==========
You can read more about it at this site but some of the details are still at the palletquonset link given above (I haven't gotten them duplicated and moved over to this site yet). I'm currently working on foundation options to permanently support the shell which will allow end wall construction and floor installation as separate projects. KISS skylights can be installed -- now or (almost as easily) later -- in the roof deck but windows and doors are confined to the vertical end walls to keep things simple. It's a huge advantage to be able to erect a weather-tight shell quickly and have a secure and dry place to store materials and be able work inside out of the weather. I also like the fact that this design -- even as a 2nd story -- can be sheathed and shingled in sections while standing inside and reaching out over the roof deck -- especially if the loft floor was installed early. Only one of the top two facets closest to the ridge would have to be finished working off a ladder). Thanks for your interest and let me know what you think.
==========
sail4free@yahoo.com
==========
==========
KAREN: "Please explain further, I know what a gothic arch is but how is one built out of pallets?"
==========
I get used pallets for free (the ones withOUT the notches cut in the 2x4s for the forklift to approach from the "side"; those are a waste of time for this application) and use my sawzall to clip the nails and take them apart without further damage to the wood. [UPDATE: Since writing this, I've realized there is a good option using the 2x4s with the notches cut in them. It requires some extra work but results in some unexpected benefits too. What we do is pre-drill 2x2s and use 3" screws and construction adhesive to attach them over the edge where the notches are. This results in a 5" deep cavity = more room for insulation AND provides a convenient "hole" for running wiring and plumbing. It also moves the inside edge of the frame inward far enough to clear the glue plates which makes interior finish much easier.] Pallets come in lots of different sizes but I've found the most common size will typically yield three 2x4s about 3' long plus the thinner decking boards -- they're also usually about 3' long. The original challenge was to design something I could build out of 3' long 2x4s. I started out with the quonset idea . . . more info at:http://palletquonset.blogspot.com/
==========
But I live in snow country and the upper two facets on the quonset are too flat to shed snow PLUS I like the look of the gothic arch MUCH better -- quonsets look a little TOO utilitarian -- IMHO. (Yet they have their fans too.) I toyed around with a modification I called the "snow roof" -- basically extending the 2nd layer of facets up to the peak but that required longer 2x4s -- a deviation from the original challenge. So I ended up applying the challenge to a gothic arch shape where the peak is 2/3 of the width of the building -- this allows all floor space to be useable without getting too tall but certainly an arch as tall as the building is wide is also an option (what I call the "full width" pallet gothic arch). I wanted the option of putting a 2/3 width arch on top of a pole-barn type first floor without the whole thing looking way too tall and narrow. Plus the angles on what I'm calling a "2/3 arch" (not knowing what it might technically be called) just seemed right and easy to work with. It is technically a polygonal gothic arch which simply means the surface has multiple facets instead of one smooth curve. On the basic design, the width ends up at 16' and the height at the peak is about 10' -- I didn't want to push my luck with the building gods too far -- some of the pallet lumber can be a little marginal. Length is optional. This results in five angled surfaces (facets) on each side for a total of ten facets for each arch. If one keeps the lower-level ceiling at 7', it's possible to build a loft floor in a portion (or all) of the space for sleeping which only uses up 1-1/2" of vertical space -- leaving more room in the loft and saving the cost of floor joists.
==========
The 3' long FREE 2x4s come together at a 15 degree angle where they are clamped in a temporary jig (constructed on the floor or the ground) and joined on both sides with plywood plates which are glued on with construction adhesive and a narrow crown (7/16") sheathing stapler (air powered). (Using plywood plates like this is common in a building method I've known as "rigid arch" where wall studs and rafters are joined together on the ground and then stood up as a single piece.) Other methods -- like hand nailing -- can be used but the stapler is MUCH faster and arguably stronger. So one piece "ribs" are created -- joined with plates of a different shape at the ridge -- to create a continuous framing piece from the floor up to the peak and back down to the floor. These ribs are placed on 16" centers just like studs and sheathing is attached directly to their outer edges. (24" centers would work also but the 16" centers allow me to use the thinner pallet decking for sheathing as well -- another opportunity for the sheathing stapler to show off AND allow us to use 1/2" sheetrock inside whereas the thicker (and more expensive) 5/8" sheetrock must be used for ceilings under frames on 24" centers.) So it's possible to frame and sheath a shell -- end walls and floor not included -- and then shingle it at VERY low cost. I priced 30-year architectural grade shingles over 30-pound felt (or house wrap) for a 16 X 36 shelter and amortized the cost of those materials over 30 years. The cost worked out to $1.15 per month for 576 square feet (not counting the loft). Now that's what I call cheap shelter!
==========
You can read more about it at this site but some of the details are still at the palletquonset link given above (I haven't gotten them duplicated and moved over to this site yet). I'm currently working on foundation options to permanently support the shell which will allow end wall construction and floor installation as separate projects. KISS skylights can be installed -- now or (almost as easily) later -- in the roof deck but windows and doors are confined to the vertical end walls to keep things simple. It's a huge advantage to be able to erect a weather-tight shell quickly and have a secure and dry place to store materials and be able work inside out of the weather. I also like the fact that this design -- even as a 2nd story -- can be sheathed and shingled in sections while standing inside and reaching out over the roof deck -- especially if the loft floor was installed early. Only one of the top two facets closest to the ridge would have to be finished working off a ladder). Thanks for your interest and let me know what you think.
==========
sail4free@yahoo.com
==========
Saturday, May 22, 2004
MOVING AIR COMPROMISES R-VALUE?
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(Posted to cheap-shelters 5/04.)
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Doug posted: "I wouldn't think it would be compromised any more than, the R value of insulation in a conventional attic space that has ventilating air circulation, would be."
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Lots of attics -- even roof decks -- are vented but it's rather passive as there is a place for the hot air to get out but not much of one for cooler air to get in. I've heard attic temps should be no more than 10 or 15 degrees warmer than outside air on a reasonably warm day -- if that gives you any idea of how many structures are NOT properly vented. Once that attic gets
hot, the whole ceiling becomes a heater radiating that heat down into the living space -- a problem made worse by "decorators" who choose black or dark-colored shingles which turns the whole attic into a pizza oven from hell.
==========
It's my understanding that Fiberglas insulation is designed to function in a "dead air" space and that air moving constantly across the exposed surface of it will compromise R value, I just don't know by how much. This particular pallet gothic arch shape is anticipated to have unrestricted air entering at the bottom of
the roof/wall arch and exiting into the mini-attic and back outside from there. So it's a concern that the minimal R value -- at least initially -- not be compromised too much by the moving air.
==========
sail4free
==========
==========
(Posted to cheap-shelters 5/04.)
==========
Doug posted: "I wouldn't think it would be compromised any more than, the R value of insulation in a conventional attic space that has ventilating air circulation, would be."
==========
Lots of attics -- even roof decks -- are vented but it's rather passive as there is a place for the hot air to get out but not much of one for cooler air to get in. I've heard attic temps should be no more than 10 or 15 degrees warmer than outside air on a reasonably warm day -- if that gives you any idea of how many structures are NOT properly vented. Once that attic gets
hot, the whole ceiling becomes a heater radiating that heat down into the living space -- a problem made worse by "decorators" who choose black or dark-colored shingles which turns the whole attic into a pizza oven from hell.
==========
It's my understanding that Fiberglas insulation is designed to function in a "dead air" space and that air moving constantly across the exposed surface of it will compromise R value, I just don't know by how much. This particular pallet gothic arch shape is anticipated to have unrestricted air entering at the bottom of
the roof/wall arch and exiting into the mini-attic and back outside from there. So it's a concern that the minimal R value -- at least initially -- not be compromised too much by the moving air.
==========
sail4free
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