A Rather Massive Roof

Well the hip was 'Piddley', and some said it was like a chunk cut out from the roof.  I personally liked it, and the reduction in mass it offered but we were also encouraged to make a simple, single gable.  Here is the result.  Still don't see any connection to the neighbours, as per the recent comment in the last post, but that is a tougher issue, perhaps, and will be worked on soon.

The taller, and more massive gable struck me as elegantly simple, though it gives the building a more serious air, compared to the cuter three-part roof.  One major excitement is the improved solar angle and the now much larger surface for solar PV modules, which are way down in price right now at about $1.73 per watt, with the required Canadian content.  I'd love to have the entire roof covered with panels, but the sizing is not working out qutie yet.  The west facade is rather plain and needs work too.

Last minute change?

We are about to demolish, excavate, and start concrete work.  Wife and Hubby disagree on the roof line!
A:  features the Hip Roof on the West side.  B: Features a gable instead.

A:

B:

What do you think?
Thanks
LT

Disconnection of Services

We've moved out of the house and have started deconstruction.

We are disconnecting services, including gas, electricity, water, etc.

Re. Electrical:
Toronto Hydro wants min. 2 to 3 weeks to perform the meter recovery, as they call it.
Our neighbours are OK with us using some of their electricity, so no temoporary service will be installed.
Re. New connection:  Underground service will require a $1000 fee for 'design' by Toronto Hydro, and up to $7000 to install.  Lead time is 14 to 16 weeks, so it could miss our foundation backfill, which means they'll dig a new trench.   Meter location is not too important now since they are using smart meters, but if the service is an overhead line, they will probably install the meter at the front of the house anyway (right near where the overhead line connects to the house).  Then we underground conduit to the back of the house, where our Utility Room is.  Conduit will be 18" below grade right beside the foundation....so this means a trench inspection, and we'll probably leave the backfilling operation short at the trench areas.
Trying to figure out where they want the damn meter.....
LT

Toronto Zoning Bylaw Repealed

On May 18th, 2011 the city of Toronto repealed its zoning bylaw 1156-2010 (and all subsequent amendments to it), which was passed into law last Aug. 27th.  This means all the little parts of Toronto are back to their old zoning systems until the new bylaw is once again prepared to be enacted - apparently in Jan 2012.  In the meantime, the Planning and Growth Management Committee will continue to consult with residents.
There was a couple of amendments to the repeal motion - They provided that 500m setbacks from concrete production and distribution facilities and propane facilities be considered separately from the bylaw's repeal - in other words, these measures, brought into force with the initial passing of 1156-2010, may remain in force...it is still unclear to me for now.
I was impressed by Adam Vaughn in the Council meeting.  He was well informed, and calmly noted that the reason to repeal was not that it was a bad piece of legislation.  Implementation of the bylaw was the real cause of the problems.  The strange thing here is - the whole emphasis on the interim period is to meet with residents and concerned parties on the content - but the PGM Committee seem poised to follow the same implementation track when it is enacted a second time - that of enforcing two zoning bylaws simultaneously.  I don't see how implementation will be any easier at that time - except that there is now a period of about 8 months when everyone can rush their projects through.  Does the PGMC really expect that everyone will hold off on their projects for a year or so while the appeals (which will hopefully be fewer than 700) are dealt with?

I wonder what all those people who paid for zoning adjustments under the new bylaw have to say about the repeal?  I doubt there is any easy way for them to get a refund on the $1700 application fee.  The cost of the lost time, redesign work, and disruption to work crews would be significantly higher, I think.

I am amazed at the absence of this issue in the popular media.
LT

Lyndon Than and Phi Than Toronto Star Article

Cynthia Vukets, a Toronto Star Reporter wrote an article about our 'passive solar house' in the Toronto Star.  Note how she does not call our house a 'Passive House'.  I find there is a funny response from some people about the word 'passive'.  Our plans examiner at the City of North York thought the name 'Passive House' was a bad name - he thinks one should be 'assertive'.
Anyway, the article appeared in the Thursday April 14th edition of the Toronto Star, Living Section, Page L7.  About a 1/2 page, discussing our project and Passive House in general.  I liked the article - but sorry, no link - I haven't found the online version. Here is the scan, click on it to enlarge.
LT

Passive House Design in Canada Series of Articles Coming Up

Hi All,
I plan to begin a series of articles discussing Passive House design and general house design together.  I will be using our own project its specific design challenges and ideas to highlight concepts.  Here is the latest rendering of our design to date.  More to come on this.
LT

Preparing the Garden for Construction

Although this long winter seems never-ending, we know spring is just around the corner! To remind us of the greenery that is surely on its way, here are some photos of the garden in preparation for the eventual demolition of our house, and with it, much of the yard.  We spent a sweaty afternoon last June moving our beloved tree peony to a corner where we hope it will be out of harm's way during construction.  In a few weeks, we'll know if the many transplants survived the winter...
-PT

Before

After

A Buyers' Guide to HRV's and ERV's for Passive Houses in North America

HRV and ERV's
http://www.greenbuildingadvisor.com/book/export/html/16744

Why Stairs are Next to Front Entries

I often wondered why in so many house designs the stairs are placed in the front entry, and I was not alone in this bewilderment.  Family and friends have sometimes fumed at it.  Why would a designer place a stair to the bedrooms (a private place) next to a front door, (a very public place), sometimes so close there is hardly a place to take your coat off.  Plus, you have to tip-toe past this dirty area in order to go to bed or to come downstairs for breakfast......Sheesh!

Now that I'm the designer, here's the other side.

Reasons for having the stair in the front entry:

1. This often helps in making the top of the stair end up in the middle of the upstairs.  Why should this be so?  Because bedrooms are legally required to have a window to the outdoors for egress purposes.  (The most dangerous time when occupying a building is when the occupants are sleeping - so if there were a fire, sleepers have a window nearby as an escape alternative).  As such, all bedrooms must be placed against exterior walls.  Therefore, to make best use of space, the upstairs hall should be placed in the middle of the floor, and all the bedroom doors open from this hall.  One way this is made possible is by having the bottom of the stair near an exterior wall.  If the bottom of the stair is in the middle of the main floor, it can be a waste of space in the upstairs to create a long hallway to get to the middle of the upstairs, which will generally be required.  Now downstairs, there is already a circulatory area near the building extremity which is lightly used - the front entry - therefore, from a space planning perspective, it is often an ideal spot for a stair.
2. To put shoes on, it is nice to have a bench, but in terms of smaller houses, to make best use of space, the stair can double as a bench for putting shoes on.
3. The stair is the one place in a simple home where there is relatively more architectural interest.

Often, it also makes sense to place a stair close to an exterior wall, since it introduces an opportunity to have another entrance to the building from a different exterior grade, especially at a landing.  This is another good use of space....although space use efficiency need not always be the final determinant in design of buildings.  Check out this hardworking front entry to a Farm house - plans available on FreeGreen.com.  Stairs, full size closet, bench and shoe storage - all the needed items, plus two ways to get to it.  And, you don't really have to get your feet dirty to use the stair.  The only improvement I can suggest would be for the stairs to be in the reverse sense so the stairs to the basement are closest to the entry.  The entry is so well used, there is no space for a powder room door, or for windows.  Bringing light in from the Entry door's sidelights is therefore important.

Prices of Vacuum Insulated Panels

I was amazed to find a corporate website giving prices for their VIP's online - but I think its such a good idea.  The lack of price information on the internet is the major obstacle to optimizing designs of any products, including buildings.  Here is the link.
http://www.glacierbay.com/barrier_price.asp.  Price ranges from a minimum of about $30/SF USD, but goes by the number of panels.  Each panel is about $345, at a max of 30"x35", and $600 for a max of 60" x 70".  Glacier Bay also provides an excellent primer on this technology: http://www.glacierbay.com/support/library_docs/vacpanelinfo.asp



Given this information, I feel a vacuum insulated door with a window should be possible to market for about $2000.  I recently received some pricing for the Frostkorken VIP door and the price seems astronomical at something like 3times that number.  Major market niche is possible here for NA.
The other company providing VIPs is Nanopore.  http://www.nanopore.com/vip.html

Window Placement in a wall, Depth of Reveal, and Psi Install

During our Passive House training, we were told recent results are beginning to reveal that the best location for a window in the wall assembly is in the middle.  The isotherms (lines of constant temperature in section views) stay as straight as possible in this situation - their curvatures to meet the window glass from wall edges is minimized.  Reduced curvature in isotherms generally means reduced heat loss.  One might even say that the distance between isotherms is proportional to heat loss (flux), but I think it is more complex than that.  In the case of the vacuum insulated panel, the isotherms would be very close together simply due to the form factor, (they have an R-rating of about R-50/inch in IP units), but the heat flux would still be relatively low.  These details need elaboration, but I don't know much about it yet....

So are Deep window wells inside Passive Houses a good thing or not?

I have been fiddling with my PHPP and reading the 'research' and find I don't find a convincing argument that they are a bad idea, which I think some people are apt to say.  Very crude experimentation with the PHPP will show that window reveals are of major importance in determining the solar gains available to the building.  Thus, placing the window near the exterior can have major benefits for overall thermal perfomance of the building, despite less favourable psi-install values.  Note that the window configuration is of significant concern here.  Where you have a very large window surface, with lots of glass compared to the perimeter, the importance of the reveal depth is reduced, and the psi-install value may be highlighted as a potential focus for further heat loss reductions.  This may also be the case when the wall is not very thick.  But when you have a very thick wall (say 24" or 0.6m), and the windows are not too big (say 40"x72"h at most), then the depth of reveal plays a major role in the building's performance - I would say a larger role than the psi-install value.  Therefore, we can still sometimes have deep window nooks in Passive Houses in cold climates. 
With respect to isotherms, you will find that the corners where the walls and sill and heads meet the opening can be chamferred.  The isotherms at these locations stay well away from the vertices anyways, so chamferring the opening where the door is installed, for example, should be fine in terms of energy efficiency.

Updated Design

Here is our latest.  The building is rectangular, with a stepped gable roof.  The long south facade presents an improved oppurtunity for solar gains, but the north face is also longer, where more losses occurr.  Of course, a large part of the gable roof is available for solar collectors.  Outside dimensions at walls are 43' x 31'.  All walls are 24" thick, and insulation values are about R70 walls, R100 Roof.  All cellulose, with likely some mineral wool in the basement.  No rigid foams or virtually none.
The view is of the South and West facades.
To give the south facade untrammelled solar exposure, we've moved the main entrance to the West side.  the challenge we now have is to make the entrance obvious and inviting.  It is almost like having one of those snout-nosed garage designs, where the visitor must travel around the garage to reach the front entrance.  In this design also, he is to travel around to the side of the house to enter, all the while remembering the importance of solar energy!  We are playing with those West roofs, and may even make them somewhat enclosed.  The building has a small enough footprint, we have room to spare in the lot coverage allowance.  The East side faces the street, where there is a balcony attached to the 2nd floor master bedroom in that tower-like stone-covered end.  Below that is an adaptable space where an elderly couple can stay on the main floor - they have an entrance to the garden under the balcony.

View from the South West.

Aerogel Insulations

Found a place where you can buy aerogel.  The product is a pelletized aerogel, rated R-8/inch.  Cost is $160/5 gallons - super expensive.  They also make translucent skylights using this 'nanogel'- visible transmittance 20%, R-20 insulation.
http://www.solar-components.com/aerogel.htm

Geo-Solar Seasonal Heat Storage

Solar Thermal is great - but if you size the system so there is no excess heat in summer, the available heat in winter is pretty low.  So the thing we all want to do is store excess heat from the summer to use in winter, and store the excess cold from winter to use in summer.

Our yearly energy demand of the house is 3600kWh for space heating, and 4400kWh for DHW, total 8000kWh.

To store 8000kWh of energy as heat, here is one option:

• Not accounting for losses from time of heat input to time of heat usage,
• Store hot water in a Tank - say we can use water from 0 deg to 80deg C (delta T is 80K)
• Specific heat of water is 1.17Wh/kgK (=4.18kJ/kgK, as 1watt is just 1J/second).
• Volume of water (M) needed:  M = E/(C*delta T) = 8,000,000Wh/1.17*80 = 85,470litres
• thats a lot of water - a tank about 3m x 9.5m x 3m tall

We can improve this dramatically if we utilize the phase change of water from solid to liquid, since the latent heat of melting of ice is 92.8Wh/kg  (=334kJ/kg).  If we utilize the water from say a couple of degrees below zero to about 80 degC, the volume of ice/water required reduces to about 1/2 of what was before (about 43,000litres, down from 85,500)  but there is then the technical problem of dealing with the expansion and contraction of the ice - which I don't know how to tackle as yet.  You can imagine that a container about 3m x 5m x 3m tall can certainly fit somewhere on our city lot.

We can reduce the storage requirement further.  We don't need the capacity to store the entire year's energy demand.  Lets say we use the solar thermal system to it's max - then we just need to figure out what fraction of the energy needs are not met in winter, and store enough to cover that much. - surely much less than the 8000kWh.  Later, we'll also have to deal with the storage losses and system inefficiencies - so the amount of storage needed will probably end up near the 8000kWh anyway...!

Geo-Solar Seasonal Heat Storage and Other Information

I think this guy has the right idea. about Geo-Solar Energy systems:
http://ecorenovator.org/forum/solar-heating/999-seasonal-heat-storage-under-existing-house.html

Depth to Ground Water/Elevation of Water Tables in Toronto area:
This information is so far hard to find, but the below links might be a start...
I need this info to consider the thermal conductivity of the earth below and around the house.  This also has important implications for thermal energy storage in the ground.  A High Water table will mean foundation structural design will be affected and heat lost form the basement may be high due to the flow and thermal characteristics of groundwater.

http://ess.nrcan.gc.ca/2002_2006/gwp/p3/a1/index_e.php
http://gsc.nrcan.gc.ca/hydrogeo/orm/maps_e.php
http://geoscan.ess.nrcan.gc.ca/cgi-bin/starfinder/0?path=geoscan.fl&id=fastlink&pass=&format=FLSHORT&search=PUBLIST%3DSOH

Cost of solar Thermal

As of Jan 2011:

• Flat Plate Collectors:  US$20/SF or $215/SM
• Evacuated Tube Collectors:  Prices are ranging from as low as $127 to $300 to $340/SM

Heating System Design

Getting around to designing the heating system:

I would love to use radiant ceiling panels - these can both heat and cool the house, and take no floor space, and do not need the concrete floor for radiant heating.  Zehnder's carboline products are expanded graphite panels with copper pipes running through.  They can both heat and cool a house.  I wouldn't need very many.  The peak heat load is about 14W/square meter, and the peak cooling load in summer is about 10W/square meter.  Delivering heat via ceiling panels is not efficient, but with heat loads so low, and the almost non-existant stack effect in a passive house, I think this might be a practical solution.  In addition, it would be very easy to supplement the heat input by heating the ventilation air a little bit.
Next comes a bunch of number crunching based on:
Yearly space heat demand:  about 3600kWh (240 sq m floor area, times 15kWh/sqm-annum)
Yearly DHW heat demand:  about 4400kWh (based on 6 person occupancy at 25litres hot water at 60degC per person per day.  Apparently this is low for NA, where the daily hot water use is more like 60litres, but typical for Europe.)

Why Install a Low-Loss Header:

The following text is from:
http://www.cylex-uk.co.uk/company-product/low%20loss%20header_2573.html

Why should I fit a Low Loss Header? 1. Your boiler, particularly the heat exchanger in you boiler, will only function at it's peak efficiency when the water velocity passing through it is maintained within prescribed parameters. Boiler manufactures should tell you what the specs are for each make and model. In some cases the flow rate through the system circuit will exceed the maximum flow rate through the boiler, or it may be that the system flow rates are simply unknown. In other cases the reverse is true, where the boiler flow rate exceeds the maximum system flow rate (particularly true in some multi boiler systems). Fitting a Low Loss Header allows the creation of a primary circuit, within which water velocity can be maintained at the required constant, regardless of changes or requirements in the secondary circuits. 2. Not only is the water velocity important, but also water temperature. There are two potential problems: the first is "thermal shock". If the temp difference between the flow and return is to great, it puts a huge strain; through thermal expansion and contraction, on the heat exchanger. Also the temperature of the water passing through the heat exchanger is important, particularly with condensing boilers, these have there own specific requirements to operate at maximum efficiency. For a boiler to go into "condensing mode" the return temperature should not be higher than about 55'C. So in some cases temperature sensors are fitted on the header to allow control over the primary circuit temperature. 3. Because of the reduced water velocity, the header is an ideal place for siting an automatic air vent for removing air and a drain point for removing sediment and debris. These are generally fitted as standard on most headers 4. The header allows separation of primary and secondary circuits for easier diagnosis when problems occur.

Aluminum Foundation, Steel Foundation for Residential Construction

So lets start figuring out these metal foundations for basements applications:

Steel:
This is actually a wood foundation clad with a thick layer of galvanized steel.  There would be a poured concrete base.  Then the actual foundaiton would be a wood stud structure, double-shelled, filled with insulation.  Then towards the outside, there would be an air space of about 1.5 inches created with something like Unistrut, though I prefer something cheaper (unistrut is so expensive).
then the galv steel cladding.  We're talking about 11 gauge (0.120 inches thick), welded or screwed (that would be annoying) to the unistrut from the outside.  Stich welded between panels.  Zinc oxide gases coming off everywhere fromo the welding, - gas masks for the welders -
I got a price on the galv steel sheet from North York Iron - $107.25/sheet (thats $.67/lb), 37 sheets (148ft perimeter on my building).  This is for a total cost for the sheets of $3968.  The sheets are heavy, 160lbs each, so not fun to handle - maybe some kind of small crane....But this way, one could make a very thin, and durable exterior shell for a building without suffering the 8 or 10 inches of concrete, probably for a competitive price.  The total shell thickness including the airspace can be about 2" or less.  On ecan get another 6" of insulation in the same space as for a concrete foundation.  The steel can be sprayed and a dimpled poly membrane installed just like a concrete foundation - for better corrosion resistance, though I've found galvanzied steel (doesn't have to be hot-dipped) holds up well.  No poisonous pressure-treated lumber involved, and carbon footprint could be similar or better than the poured concrete.  Thermal expansion co-efficient of the steel is similar to concrete, so not an issue.

Now:  Aluminum foundation:  Same idea as the steel, but no corrosion issue, unless you have a very salty and wet soil....Using the same 1/8" thick sheets, the weight of each sheet will only be about 53lb.  Lighter than a sheet of fiber-cement or drywall - much thinner, of course.  I would not weld these in place, I would use aluminum brazing, although corrosion-resistance of the braze would need to be checked.  This way, the foundation would be sealed entirely, and fastened well at the same time.  I would skip the dimpled membrane and spray.  Apparently the price of Aluminum is about $.65/lb - at this price we are looking about $35/sheet of 4'x8' - cheaper than 3/4" S1S fir plywood!
At first I thought thermal expansion would be an issue, but note that the ground temperatures are pretty stable - fluctuating only some 10 degrees C or so throughout the year.  But thermal conductivity of Al being so high, one might start to wonder if the ground around the foundation would get quite cold, even at the bottom - Hello Therm simulation.
LT

Fiber Cement in Below Grade Applications

I'm looking (without success) for a thin, impermeable sheet-like product for use in a below-grade exterior application.  What I want is a material like fiber cement, which is very thin, fire-resistant is good, and hard, and hopefully impermeable.  I'd like to apply it below grade like a very thin impermeable sheathing on a wood-framed below grade curtain wall.  I don't want pressure treated plywood due to its environmental issues.  Fiber cement seems perfect, but I just spoke with a Tech rep at James Hardie and he completely seems against the idea.  The product is made, he says, of type 2 cement, silicon, and wood fibre, and absorbs water.  But so?  Concrete absorbs water too - and we just damp-proof it with an asphaltic spray and apply that dimpled HDPE membrane below grade. - Or not.  Why not do the same with Fiber-cement?  I can resort to sheet aluminum, perhaps 1/8" thick.  This is certainly impermeable - but coefficient of thermal expansion is high - still maybe OK.
Next option - Fibreglass sheet - like those circuit board materials, only thicker.  Concrete sheet is thin, of course, that is an option, but costly as well.  Plastic Sheet - PVC is eww.  But perhaps HDPE, or PEX sheet?
Lyndon

No Stack Effect in Passive Houses

During our Passive House Consultants Training in Summer 2010, we were told empirical evidence is revealing is there is no stack effect in Passive Houses.  I'm referring to the way heat rises.  In normal buildings, the upper floors are warmer than the lower floors of buildings.  And tall rooms can be expensive to keep warm in winter because all the heat rises to the ceiling, while the occupants remain on the floor.

I found this claim of no stack effect fascinating but didn't know why it might be so.  After some thinking, I feel the answer is in the surface temperatures.   For stack effect to occur, there must be differences in air temperatures in a building.  In passive houses, all the interior surface temperatures are within 3 degrees C, throughout the year.  From our trainings, I understand this is even on the coldest day in winter, and on the hottest day in summer.  This means the stratification of air in the house is minimal, and that there is very little drive for stack effect to occur.  I would think in fact it does occur, but to a small degree only.

If you imagine a room full of air and the air is of varying temperatures, you expect that the warmer air will migrate slowly upwards while the cooler air stays lower, but what about all the air in-between?  If regardless of the room's height, all the air is within 3 degrees, one would expect a linear progression from one temperature extreme to the other.....so in a room 10ft high, the floor-air might be 18deg, while the ceiling-air is 21deg. At 5ft, the air might be 19.5deg.  All of this would be with no motion of the air at all.  Now if the heat source were near the floor and blowing a slight amount, there will be minute currents of air moving throughout the room.  You can see how this is getting pretty un-important, with these low temperature differences.  On the other hand, with a 10-degree C differential or more like in a regular building, the stack effect (and drafts of cool or warm air) might reasonably become much more noticeable.

LT

The New Economy House

Marianne Cusato has designed an interesting house, not very big, but with 4 bedrooms, that can be built very cheaply, and provides some flexibility in living - perhaps even a rental income.  I found this approach very to our liking and thought, why not redraw this house as a passive house?
You can see the New Economy House here:  http://www.neweconomyhome.com/Site_2/Floor_Plans_-_NewEconomyHome.com.html.

Things I noticed about the New Economy House:

1. Not too much provision for a hall closet - if you wanted to have a basement, with stairs underneath the existing staircase.
2. Bathroom layouts upstairs are a little tight.
3. 2' thick walls leave the windowed facades quite a bit different looking from the original
4. the 30" thick roof similarly has a strange appearance that needs to be addressed.

Here is a visual: