Thursday, February 25, 2010

Couple of renderings from Revit. Neighbours house on the southwest side is included. This first one is the rear, and the second one is the front again - South side.
Sun is modelled as at noon on the winter solstice, but it's probably off by about 15deg since I haven't adjusted the house orientation. The aerial view in the previous blog is aligned to true north, so you can see the streets are tilted pretty close to 15deg to the west.

Aerial View

Thought I would post an aerial view of the existing property. The big round thing is a 13ft trampoline. Anybody want a trampoline? It's really going to get in the way. We also have a ping-pong table we need to get rid of.

Friday, February 5, 2010

The below pic is of the existing house on the property. Pic is from Summer 2009, from Google Streetview. This is the south side.

Some notes on the design:

1. We aren't architects.
2. Passive house requires volume to surface area ratios be favorable to energy conservation, so a simple, square-ish box meets the need. We had sketched a number of modern designs, but there were issues. The existing garage form is more traditional, and would have to be revised to relate to the modern design, and the height limitations are more restrictive to flat roofs (8m, instead of 8.8m to the mid-point of a sloped roof). A traditional gable is proving more spacious inside, works with the existing garage, and will relate to other houses on the street.
3. The square box is stretched in the east-west direction a little to increase the south facade, while the diminished north-south dimension means more of the light from south-facing glass (few, and very small north-facing windows are a strong need of efficient houses) will reach the back (north) side of the house.
4. The main floor is raised 3ft above grade to increase window areas to the basement, and make basement space more pleasant. This places pressure on the upper floors to keep ceiling heights modest and floor assemblies thinner. As shown, there is enough space for floors 12" thick, but just barely.
5. House dimensions are 41.5ft x 34.5ft, excluding porches, which are generally not included in lot coverage and setback calculations.

Fig 1: Site Plan

Fig 2: Viewing North-West

Fig 3: Viewing South-west

Well, here is an early version of a house design in which we've worked out a number of things, including main and 2nd floor plans, and exterior features to some degree such as windows. The exterior detailing is not really given attention yet, so there are little things to sort out. The house is tall (about 34ft or 10.5m) in this drawing, which means blending into the street-scene could be an issue, so the tall trees (12.5m oaks are shown) are intended to help in establishing context - However, the tree on the left in Fig 2 is right where a hydro-pole is, so there are issues. The curving drive is really sweet, in our minds. The lower 'shrubs' you see are 3m (12ft) tall and thick cedar hedges already existing on the site, as is the separate garage. The Revit model didn't have much available to make them look more realistic.

We intend to bury the electrical service to the house to get rid of that nasty wire running across the property.
Height is measured to the mid-point of the roof, from the crown of the road - there are two roads abutting the property in our case, so I've taken the highest point available from these.
The view shown is the south facade with the larger windows. the Passive House software was already applied to the model and there seems to be no problem with meeting the heat load and the annual energy requirements - but there is a little too much sun in summer, pushing 50% of sunny days over the 77degF comfort limit, but that is probably because I haven't entered all the shading factors as yet, not knowing the tree choices and locations.