Ideal floor plans for wood heat?

[peakbagger]

One of the things to consider with energy efficiency is surface to interior volume ratio. Meaning add up the exterior walls area and divide by the interior volume. About the most efficient design is half a beach ball, dome, but most people have a tough time with corners and aesthetically they are tough. The monolithic dome institute has been an advocate of dome home for years https://www.monolithic.org/ hard to match them for energy efficiency and resistance to high winds. Lots of public buildings that got wiped out by tornadoes have been replaced by them but most feel they are ugly. One minor step from a dome is the geodesic dome. They were the rage at one point and gave a bit more surface appeal but well known to be difficult to keep watertight. I think most would say they are more attractive than a monolithic dome but that is faint praise. So the goal them is fit a rectilinear structure in a dome. That would probably be a hip roofed home but hip roofs have a lot of wasted space. The next conventional home is probably a New England cape. The trade off is 2nd floors are hard to access for those mobility challenged. A ranch is probably the least efficient surface to volume wise but easier for mobility.

My house is a relatively square 28' deep by 32' long full dormered cape on one side. The dormer is facing south for better sun and the views while the back roof is facing north. I have a 4' hip wall in the back of the second floor. I would have gone even "squarer" with the house but its a modular first floor and at the time 14' wide was the max over the road without a police escort. The house is laid out with one bedroom, full bath and laundry room along with kitchen and living room on the main floor with 3' wide doors which at the time was regarded as extra wide (standard was 32"). That was 30 plus years ago and I have learned a few things. I have a double flue masonry chimney at the center of the house with one oversized flue. It would be repalced with chase with smaller flues but would still exit next to the ridgepole. It could easily have an additional 1st floor bedroom added. The only access issue is it requires a climb up 4 stairs to get inside from outside. I could add a ramp if needed.

 

[begreen]

I think this is exactly correct. A one room cabin, however spacious, easy to heat with wood, no door on the bathroom.

Privacy can be built-in by lofting a bedroom and having an entry partition for the bath. What has not been indicated is how large the home would be.

 

[begreen]

@peakbagger , there is a group of folks on a timber framing forum I belong to - that double check each other's beam calculations. None are offering engineering stamps, just double checking the math. One of those folks is building in the Sierra Nevada with ground snow load over 100 psf and went down the roof pitch rabbit hole to encourage snow to slide off. He was up to 18:12 pitch last time I checked in.

At the end of the day, the vast majority of ready made plans are for ground snow loads "up to" 50 psf, so the rest of us get to do some math. I am roughly equidistant from the South, North and West coasts of Alaska.

For now I will stick to an interior floor plan with minimal walls and minimal doors, and not worry about construction techniques until closer to trigger time.

Thanks all.

A friend built a large, timber-framed house in Haines, AK that was mostly open floorplan. The main floor all was open except for the bathroom and a small TV room that had doors. It was 3 stories tall with a wide, open staircase connecting the second floor where the bedrooms were and a spiral staircase to the 3d floor office. Heat convected easily in this space.

 

[Newbie78]

Cool house! It needs a lift...at least MY knees think so..

 

[EatenByLimestone]

I’m giessing that 3rd floor is well sealed to avoid chimney effect?

 

[Poindexter]

My tentative plan, given local prices, is to bring in a two story 3 bed/ 2 bath house under 2000 sqft total.

As pictured coming into the house through the entry door is a woodstove pushed just far enough back for the chimney to pierce the roof behind, but otherwise adjacent to the ridgepole. Stairwell on center on the back wall.

Kitchen lower level to the left of the stairs. Both baths to the right of the stairs, one up and one down. Two loft spaces upstairs sharing the common stairwell. Currently no interior walls drawn or planned, other than support for the stairwell.

I have drawn the two loft spaces (pink highlighter) not reaching the L and R end walls for some open-ness and convective options, with hopefully just handrail around all the perimeter.

Wheelchair accessible bathroom will take up a lot of sqft downstairs.

Having an upload issue. Hope to resolve that before the edit window closes...take two

 

[EbS-P]

My tentative plan, given local prices, is to bring in a two story 3 bed/ 2 bath house under 2000 sqft total.

As pictured coming into the house through the entry door is a woodstove pushed just far enough back for the chimney to pierce the roof behind, but otherwise adjacent to the ridgepole. Stairwell on center on the back wall.

Kitchen lower level to the left of the stairs. Both baths to the right of the stairs, one up and one down. Two loft spaces upstairs sharing the common stairwell. Currently no interior walls drawn or planned, other than support for the stairwell.

I have drawn the two loft spaces (pink highlighter) not reaching the L and R end walls for some open-ness and convective options, with hopefully just handrail around all the perimeter.

Wheelchair accessible bathroom will take up a lot of sqft downstairs.

Having an upload issue. Hope to resolve that before the edit window closes...take two

View attachment 307403

Bedroom on the first floor too right. Laundry in the??? All the wood comes in the front door? Garage?? Thinking of stove placement and second entry door close by. Which is you wall of windows?

 

[maple1]

I agree with this, but I don't need to be a guinea pig. Among currently 'proven' cold climate choices I would choose LEED 10 before the remote wall system recently advocated by the CCHRC (cold climate housing research center) at UA Fairbanks. The trouble with the REMOTE system is those darn 9" screws sag over time, leaving a gap in the insulation envelope at the top of the walls where they meet the ceiling insulation.

When/ if I do build I will be going with the latest greatest proven tech, distinct from the latest/greatest tech that should work.

And I am putting in AC. If I build, it is simply not negotiable. Summers up here are now too dang hot to do without a couple mini splits pumping cold air while the sun is shining anyway. So the insulation envelope will need vapor barrier inside and out; and there will be solar panels.

Well, if you're going to do mini splits, and build to the standards you are speaking of, you might not even need wood heat. But keeping it as open as possible would benefit both.

 

[Poindexter]

@EbS-P , in a very general way I plan on a second exterior door in the kitchen area. I think a stacking washer dryer in the kitchen area should be adequate for that season.

First build on the lot I don't own will likely be a two car garage at ground level with a stairwell to an end and a 1/1 apartment above. Once the big house is done we can move into the house and rent the apartment.

At this point imagine the left wall facing SW, the front wall with the entry door facing SE. It might make sense to move the kitchen to the East corner and keep all the plumbing on the NE wall, but it doesn't change the floor plan.

 

[Poindexter]

Which is your wall of windows?

I am committed to windows on all four walls. I am not committed to a wall of glass.

I do appreciate the potential view, but in my local experience it is hard to make a room warm enough to feel warm when the snow is flying. Also, light colored well fitted blinds and bright indoor lighting can make wintertime darkness feel further away.

Beyond purchase price and ongoing BTU loss, coming up with well fitted blinds is an additional added expense to walls of glass.

 

[begreen]

I’m giessing that 3rd floor is well sealed to avoid chimney effect?

The whole house was built quite tightly with good attention to insulation and sealing. Their main issue was power, it was off-grid for 5 yrs. running on wind and batteries. It was a pita to maintain. He finally got fed up and organized a hydro district for the neighborhood fed by a distant turbine on a waterfall.

 

[ABMax24]

I am putting in AC. If I build, it is simply not negotiable. Summers up here are now too dang hot to do without a couple mini splits pumping cold air while the sun is shining anyway. So the insulation envelope will need vapor barrier inside and out; and there will be solar panels.

Make sure your exterior vapour barrier is still permeable, Typar or Tyvek is what's used around here. Otherwise 2 impermeable vapour barriers will have mold growing inside your walls.

 

[DBoon]

Spend time doing great air-sealing - do it yourself because no one else will do it better. I used VP100 Blueskin on the exterior of my house as well. My house infiltration is better than 1 ACH50 and I still have most of the original wood windows (also weather sealed with gaskets and bronze weatherstripping). Also, check out "larsen truss outside wall" design on Google - allows for a thick, well-insulated wall without any or minimal foam board on the outside and the wall construction can be filled with low-cost cellulose.

 

[BK's_ghost]

As long as the place isn’t huge it doesn’t have to be complicated. I think having two stories and a central stove in a big room near the stairs can do it.

I’m going to self congratulate and put my own floor plan out there. First year burning in this location, but so far it is working great. The upstairs bedrooms get reasonably cold, but that just feels preferable and efficient to me. All rooms open to the stove room or landing at top of stairs. Biggest problem is the kitchen being cold. Some ducting could likely replace the single distribution floor fan we use to get the heat into there, or in an ideal plan the kitchen could be worked into the big one lower floor stove room. The house is old construction and in a fairly cold climate.

 

[Nate R]

With the suggestion of the "Not so big house" book, I'll also throw in a suggestion for the newly published "Pretty good house" book by several authors. Provides a good list of things to think through when designing a home..... Basically with the aim of building a house better than code, but not necessarily passive-house levels.....and making sure you stick $ where it makes sense. (No sense in paying for a double stud wall if the heat loss from your skylight or double pane windows outweighs it... maybe a single stud wall with triple pane windows makes more sense, etc)

I'll offer up this: Make sure you have intake air for the stove, or at least the ability to add it, and controlled air for the home.

Pretty Good House

The Pretty Good House approach to home building and renovating details a pathway to building better than code minimum which describes the worst house you can legally build. The info is vetted by leading experts in the field of fine homebuilding, high performance and green building and the profession

www.prettygoodhouse.org

 

[Poindexter]

wrt post 31 I settled on 28x35 footprint (980 sqft for the lower level) This makes room for 6 "areas" at roughly 12x14 feet on the lower level.

Made a scale model today, 1 inch to 7 feet.

I did leave room between the second floor ceiling and the cold roof above for 40" of blown in corner to corner, but it means the fenestration needs some vertical massage.

Mrs. Poindexter wants to see the loft area installed.

 

[peakbagger]

Fancy. A nice way to work up concept if you are not into CAD. I am still in the 2D stage but at some point will drag out my rusty and primitve 3d skills.

Out of curiosity have you modeled the windows?. Its pretty rare in energy efficient design to see windows on three walls as the winter sun angles means many of the windows are net energy losses and at best only get reflected sunlight. At my latitude (44.38)the window "budget" is usually spent on the south wall with either fixed or preferably adjustable overhangs/louvers/landscaping to deal with excess summer heating. At a minimum, the north and the prevailing wind side usually gets few if any windows except for egress if needed. My house was not modeled when I designed it long ago and I regret putting in several windows on my west wall which is the shaded prevailing wind side. I have double cellular blinds on the ones in the finished part of the house and find that the blinds are rarely if ever opened. If I do not build a new house I am considering a major energy upgrade/reno on the current house and plan to replace the two egress double hungs with smaller casement or Euro super energy efficient windows. The one bedroom that would be affected has egress windows on the south wall and other is half bath so no need for the egress windows that are there. One of the rooms is a bedroom and I have the foil backed cellular blinds so no light transmission but I do find that the standard ones let in lot of diffuse light on a sunny day. I think that was the approach that Kalwall advocated years ago, translucent fixed wall panels to get the diffuse light but far higher R value than glass.

 

[begreen]

As long as the place isn’t huge it doesn’t have to be complicated. I think having two stories and a central stove in a big room near the stairs can do it.

I’m going to self congratulate and put my own floor plan out there. First year burning in this location, but so far it is working great. The upstairs bedrooms get reasonably cold, but that just feels preferable and efficient to me. All rooms open to the stove room or landing at top of stairs. Biggest problem is the kitchen being cold. Some ducting could likely replace the single distribution floor fan we use to get the heat into there, or in an ideal plan the kitchen could be worked into the big one lower floor stove room. The house is old construction and in a fairly cold climate.

View attachment 307645

Our house is a variation on this layout, with a more square perimeter. For a 1926 house, the first floor is remarkably open. With the stove in the LR the heat distribution is very good. I had to put a false transom (dashed line) in to slow down the flow of heat to the 2nd floor up the main stairwell. Something to think about for a 2 story design.

This is a rough layout of the first floor. The second floor has 3 bedrooms. Total sq ftg 2,000. It has lots of windows, too many, as a result of multiple remodels over the years. Not ideal for heating, but passable in our mild climate. They were put in for the views and to increase light.

 

[woodgeek]

I have a 1960 side by side split level with a two story foyer/entryway. The whole house is one zone and one tstat (with a couple remote sensors). To keep the balance good with either the central HVAC OR wood heat, I use a silent, DC-motor ceiling fan on the top of that entryway. That has the highest CFM/watt of any way of moving/mixing air, much better than the central blower or smaller fans. The airflow also speeds the drying of wet gear in the mudroom two stories below.

My concern with OP's design is the kneewalls on the loft story. The framing on such spaces (as in a Cape Cod house) is VERY hard to properly airseal, let alone insulate.

 

[peakbagger]

I think the approach with knee walls these days is assume they are not there and air seal and insulate the roof behind it. The knee wall is still there but no insulation. My knee wall was insulated prior to the foam being added to the roof so they left it in. A good thing as I have lot of foam shrinkage with big cracks in the foam that I need to deal with someday.

 

[Poindexter]

My plan is for similar windows on all four walls.

Once I have a lot and have chosen a site on it and know where the wind comes from and what the existing trees are, then I can think harder about windows, or translucent panels. Or even headered openings in the framing now for future windows or even passageways into an extension later.

I may need to blank out a couple of the windows for the home theater system screen on an exterior wall, but I would rather not.

I loathe, simply loathe, rooms in typical suburban homes with one small window on one wall, and three walls of surface on which to store stuff. Having windows on two walls in one room elevates the space, in my mind, from a simple cave in which to survive to a civilized space in which to think.

The potential for 360 degree views from the loft, save the bathroom at the top of the stairs, is thrilling to me.

The point about knee wall insulation is not lost. Having a great hat and a great coat out in the weather with no neck wrapping is a similar wardrobe malfunction.

 

[BK's_ghost]

Our house is a variation on this layout, with a more square perimeter. For a 1926 house, the first floor is remarkably open. With the stove in the LR the heat distribution is very good. I had to put a false transom (dashed line) in to slow down the flow of heat to the 2nd floor up the main stairwell. Something to think about for a 2 story design.

This is a rough layout of the first floor. The second floor has 3 bedrooms. Total sq ftg 2,000. It has lots of windows, too many, as a result of multiple remodels over the years. Not ideal for heating, but passable in our mild climate. They were put in for the views and to increase light.

View attachment 307784

My stairwell is only open on the lower level to a standard doorway size entry, the rest is walled off. So I agree with begreen and that the ‘ideal circulating’ house probably has some way of flow metering to the upstairs with a transom, doorway, or other geometry/location. That way the house isn’t relying on a fan pushing air back down.

One thought on windows. If you run a thermal nighttime setback, east facing windows can sometimes feel very worthwhile during the warm up period, even if the don’t pencil out objectively.

 

[Max W]

Poindexter, I like that you made a mockup. That can reveal many things that a two demendional floor plan cannot. On a new design and build we tossed a plan after making a craft board model. In addition to some space problems it was clear that enough of our existing furniture just would not fit and buying new was not on our minds or budget. Another mockup showed a plan that did meet our needs and a house that lived up to expectations.

 

[Sawset]

Having windows on two walls in one room elevates the space, in my mind, from a simple cave in which to survive to a civilized space in which to think.

This may be of interest to you, chapter 159:

APL - Home

www.iwritewordsgood.com

There are also a lot of other ideas there too. One thing I found extremly useful was a simple floor layout software that can put up some walls, windows, doors, then do a quick walk through. I would find some home plan, spend a few minutes laying it out, walk the little guy through, and realize the plan was unworkable. Dead end walls, window layout dull and "cave" like, views within framed views were missing.

 

[begreen]

I’m giessing that 3rd floor is well sealed to avoid chimney effect?

The is just the spiral staircase opening to the third floor.