Designing with expansion in mind

I have noticed that small buildings get built quick and large ones take a long time and can be too expensive... some are abandoned partly finished. Looking at old farm houses and even some in town, I have seen two methods of dealing with this. The first is to build small and then build bigger and use small for storage. There are a lot of farms around that have two or sometimes three houses in graduated size, the first often being 200 sqft or less (now used as a tool shed or chicken house). Then there are others where the house has been expanded as needed. Sometimes there is a mix. In the case of an earth berm house, is there a better way of the two?

Building small and then building big: The advantage of this would be that the new build would not suffer from mistakes made in the first build. It is a chance to start over. Also, the building would fit together as a unit and not seem pieced together. The disadvantages might be: Cost. There is still the cost of building big. The project could take longer because there is no hurry to get finished before winter, but leaving a part finished project in the weather has it's own problems and so it may have to at least get to a certain point at whatever cost. If it is a permitted structure, there are time limits on the permit. The permit can be extended (for a fee), but the extension may require the permit to be re-approved. (just from reading the building by-laws in our area)

building small and expanding: This can be pay as you go. Each part can be done quicker and cheaper. If the first part is on a permit, it is easier to stay on budget. If it is on permit, it is a known building, Extensions can often be added later with no permit if done quietly. Google satellite photos are not as much of a threat as with a new non-permit building on the sly. (I am not advocating one plan of action over the other, just talking reality) The disadvantages are: living with old problems. Tearing down some old build or removing berm. Extra planning in the first place. In the case of an umbrella it would be hard to extend or would have to be big enough for the whole building in the first place. Special attention would have to be given to any joins from old to new and to not damaging the old umbrella where it was being kept. A berm structure could have the berm left off on the side(s) where additions were to be made. It would be best to try and decide the final use of the original part before starting.

Len Ovens wrote:
building small and expanding:

I am guessing a third option is to design for possible expansion if you end up going that way or not. Or design as finished but be willing to expand the hard way (rip and tear).

With the wofati or earthship and variations, the design is generally along the hill or perpendicular to south. This means expansion is most likely to be off one end. The earthship is often done in bays so another bay (or five) could be added. I don't know what splitting a wofati into bays would do to it's operation. It might be interesting to have one section offset from the other (not in a straight line). Three sections with the centre offset could create a courtyard with micro climate or follow the curve of a hill.

I am thinking wofati does not have to mean square or rectangular shaped either. I wonder what the best shape would be ("for what" is the question I guess).

Howdy Len,

If you have access to pine logs, you might like my dream home. Someday I hope to build a hogan. As they have eight sides I was going to expand by building a second hogan attached to the first. If the years are good to me I will continue to add on, creating an enclosed yard with hogans all around. Eventually might even be able to put a big roof over the whole thing.

I think the hogan can be built to be earth berm or wofati.

Miles Flansburg wrote:Howdy Len,

If you have access to pine logs, you might like my dream home. Someday I hope to build a hogan. As they have eight sides I was going to expand by building a second hogan attached to the first. If the years are good to me I will continue to add on, creating an enclosed yard with hogans all around. Eventually might even be able to put a big roof over the whole thing.

I think the hogan can be built to be earth berm or wofati.

Yes the earliest hogans seem to be earth berm and then it seems to have become a round log house in it's latest forms.

I have been reading about pit houses, dugouts, several other names for the same thing it would be great if they all linked together for houses built basically the same way.

The point ends up being that people of old were much more used to being chilly and living with it. That is they let themselves acclimatize daily and maybe even hourly as well as seasonally to varying conditions. Using the earth berm style of construction did not give them 72F in their homes, but at least made "camping" livable inside.

Second these people had no windows. There was a balance between having light to see enough what they were doing (from both outside and the fire) and loosing heat. Most of the original houses were dark inside.

Third, the homes were smokey inside. There are two sides to this.... smoke kept the insects away and so was considered a resource, or it was hard on the eyes, throat and lungs.

Wofati, takes these traditional styles and their strengths and adds glass, hinges(AKA doors) and a flue. Vapor barrier (though they did use various things to keep water out) might be included in that too. These things help to cover the bad aspects of these buildings. So the main thing is that we can get light (and solar heat) from any desired direction without the draft and we don't have to let our heat out the roof with the smoke. This also helps with the dampness. Hogans, pit houses and dugouts were designed to make the most of their problems, the roof hole served not only to let smoke out, but also for light and egress. So the round shape was was also a part of the design, no part of the dwelling was too far from the light, fire (warmth) or a way in and out.

With todays underground/berm dwelling, the new elements determine how the dwelling is shaped and laid out. Closing things in means being right in front of the fire is not required for all activities. Even though we want to heat people and objects rather than air, the air temperature is higher than with a big hole in the roof (though still lower than some permit requirements). With doors we can have as many entrances/exits as we want... well maybe not Anyway the point is that the shape and layout should make the best use of all the design elements, not just those that worked with open fire and no doors or flue pipe.

I was going to say we are not used to living in the dark, meaning without outside illumination, but I notice my wife is happy to have closed drapes all the time. That leaves the question of how much artificial light we are going to supply. The open fire would have supplied all the night time light in old style homes, but we are going to put our fire inside a lump of mass to make the best use of it's heat. If we are to use solar electric lighting then are we going to have the roof space to do so? Will we have it off to the side? Will we use oil lamps? How will we deal with their smoke and oxygen requirements.

The one thing the old style did have though, that outshines any of today's houses.... is fresh air.

Len,

I have felt for many years that the degradation of starter home neighborhoods could be at least partially alleviated by insisting that yards be big enough and that homes be designed with expansion in mind (not really all that difficult). Young couples often move into a starter home with a 3-year plan in mind. Once the first wave starts to leave, it begins a cycle of lowered home prices, then desperate owners start renting their homes and the cycle of blight is complete. One of the observations I have heard from many of these young couples is that they had gotten used to the neighborhood and would have preferred to stay, but they needed a bigger place for the kids.

Applying this concept to earth-sheltered construction is somewhat problematic. A PAHS basement house that was bermed but not dirt-covered could serve as an efficient foundation for vertical expansion. [If you think in terms of the umbrella covering the insulated dirt and not necessarily the house, it might make it easier to accept this approach.]

Andrew Parker wrote:Len,

I have felt for many years that the degradation of starter home neighborhoods could be at least partially alleviated by insisting that yards be big enough and that homes be designed with expansion in mind (not really all that difficult). Young couples often move into a starter home with a 3-year plan in mind. Once the first wave starts to leave, it begins a cycle of lowered home prices, then desperate owners start renting their homes and the cycle of blight is complete. One of the observations I have heard from many of these young couples is that they had gotten used to the neighborhood and would have preferred to stay, but they needed a bigger place for the kids.

I also think that if the family built their own home, they would be more attached to it. They would own a larger portion of it making it more their's and less the bank's. A permit system that made this possible would be great too. this would making expansion easier too. The long term result would be that rentals would start to disappear as owner made housing would make ownership possible to much more of the population. I think it would also make a better community as someone who has built their own home feels happy about helping someone else who is doing the same thing. I am not saying this would change human nature, but it might change community.

Applying this concept to earth-sheltered construction is somewhat problematic. A PAHS basement house that was bermed but not dirt-covered could serve as an efficient foundation for vertical expansion. [If you think in terms of the umbrella covering the insulated dirt and not necessarily the house, it might make it easier to accept this approach.]

In my thinking, and I have not tried any of it, the floor of the living space needs to be connected to the mass. My reasoning is that high mass housing tries to keep the occupants warm by direct radiation rather than air temperature. I have nothing against the mass being just on the bottom and not bermed, but I do think the mass heat storage needs to be connected to the living area. However, what heating of the air does happen will rise and (even though the idea of a PAHS home is to heat itself from the sun) most of these places do have some heat for the main room. (living room/family room/great room/where ever people sit around) So a second floor may work in that case.

My latest thought, based on what Miles Flansburg wrote:

If you have access to pine logs, you might like my dream home. Someday I hope to build a hogan. As they have eight sides I was going to expand by building a second hogan attached to the first. If the years are good to me I will continue to add on, creating an enclosed yard with hogans all around. Eventually might even be able to put a big roof over the whole thing.

The idea of building a whole second building as an expansion rather than a direct extension would allow the first (and second) building to be built whole in concept. Therefore it could work as designed in the best way. I do like the idea of a surrounded court yard in concept but I am not sure that all of the surrounding buildings would still enjoy optimum siting. The underground house that the wofati is based on (I don't see it as underground actually as both front and back walk out on grade... even if that grade is sunk), had a courtyard between the home and the hillside. I think that the side of the courtyard away from the house being walled meant that heat radiating out from the windows was partly reflected back in through the windows and meant less heat loss. The first wofati hasn't had time to have such a wall to be built so we don't know if that would help in this case. Interesting to think a wall outside the house itself might affect heat loss/retention. The courtyard makes a bit of a micro-climate.

The trick with extending by building a second building (aside from the connecting passage) is to not have too many walls in the first building and to design it with a primary purpose ( the purpose it will have after the second building is added) and then make the secondary purposes work within that frame work.

... Still thinking.