[UPDATE MARCH 2016: since this post was written, Leanne and I have entered into a contract dispute with Ridgewater Homes. For more details, click here.]
It was my last chance to give you a good look at the way the basement was.
On Friday Ridgewater and Nickel Bros. will team up to lift the house up and support it on six cribs (which look like Jenga piles, but I’m sure they are much sturdier).
Here is a video walk around and guided tour. It’s 2m21s long.
A lot of people ask me how high we are lifting the house.
I answer that we are lifting it high enough to dig the basement deeper, pour a new foundation with super-de-duper insulation and put pipes in the basement floor for radiant heating. After that, we will put it back down to more or less the same elevation.
That’s when they give me a puzzled look. It’s a look that says, “you already have a basement and a foundation so why are you going to all this expense and effort to gain a couple of feet of basement ceiling height, a better foundation and more insulation?”
That’s what you’re thinking isn’t it? You look at this colossal project and think that there must be something seriously wrong with the house for us to go to these lengths. If not then why? Why not settle for good enough?
I’d like to tell you it’s because we’re going to recover the cost of this reno in savings on our fuel bills.
But I don’t think we will.
I’d like to tell you it’s because our energy advisor, one of the best in the province, Monte Paulsen, told us it would be a good idea.
But he didn’t. In fact he kinda tried to talk us out of it.
In fact, I came to the answer during a conversation with Monte a couple of months ago. The answer is, “because we want to.”
It’s a little more complex, I guess, but I want you to know that I’m not trying to tell you what you should do with your home because I can only speak for what we wanted to do, what is important to us and what brings us joy.
So why did we want to?
Mostly because we are fed up with the glacial pace of humanity’s response to climate change. We want to go further and do more.
I mean seriously, in 2013 the Canadian National Roundtable on the Environment and the Economy, chaired by former Governor General David Johnston, released a report called, “Paying the Price: The Economic Impacts of Climate Change for Canada.” The report introduction states:
Canada – the fourth report in the NRT’s Climate Prosperity series – is the first national study to show what the economic consequences to Canada could be as a result of climate change, under four separate scenarios involving two factors: global GHG emissions and Canadian economic and population growth.
Although Canada contributes approximately 1.5% of global emissions, the report concludes that climate change impacts brought about by increased world-wide emissions have a real and growing economic cost to Canada. It also shows that adaptation – our capacity to manage the impacts to come – while not cost-free, is a cost-effective way to alleviate some of those impacts.
Based on NRT original economic modelling, the report finds that the economic impact on Canada could reach:
2020: $5 billion per year
2050: Between $21 and $43 billion per year
Just how much are those forest fires costing British Columbia right now in 2015?
This is valuable Canada-specific analysis and speaks to the need to address the problem head on. Instead, we are subsidizing the oil and gas sector and have eliminated job-creating incentive programs for home energy retrofits like Hammond Forever House. We are buying more gasoline cars and quibbling over how to pay for desperately needed regional transit.
Oh, and after the report’s release, our Conservative government hastily shut down the National Roundtable in the name of belt-tightening–as if stopping the flow of information will make the problem disappear.
Can we blame consumers who choose to install new countertops instead of insulating their attics? Yeah, okay, but aren’t we all just trying to get by and eek out a little happiness for ourselves and our kids? Aren’t we bombarded with advertising all day every day? Making us feel guilty about stuff we buy isn’t going to help!
Can we blame politicians who seem unable to act on the mountain of evidence that is at their fingertips? Yes, but when you are running to be elected for a four-year term, is it courage to propose investing in climate change mitigation and aggressive greenhouse gas reduction? Is it courage or political suicide? Our Conservative Federal Government is pretty voter-savvy, and they always choose to send a small cheque to voters instead of actually solving problems. I think a lot of us see through this doggy-biscuit tactic, but it seems to work. Can we blame them for doing what gets them re-elected?
With climate change, we all seem to be waiting for someone else to act. Oil companies and car manufacturers have billions of dollars to insinuate their messages into our brains, but who is telling the other side of the story? Scientists publish results, but they don’t advertise. Contractors make more money building a new house than retrofitting an old one. Homeowners who are passionate about reducing their carbon footprint are usually too busy doing it to tell the world about it.
That’s why I’m sharing this journey with you. I’m not pretending to be an expert on heritage houses and home energy retrofits, but I will share what I learn with you.
Now let me introduce you to an actual expert. Monte Paulsen of Red Door Energy Design got involved in our project via our architect, Annabel Vaughan. I can’t blame our decisions on him because I was already pushing for an extreme energy retrofit before he came on board. He was the one who questioned spending $300K on a $400K house and he has questions about promoting the idea of “Net-Zero Energy” as a reasonable goal.
I’m going to post Monte’s entire Preliminary Modelling Notes for you now because I know that some of you are going to geek-out and eat it up. It gives a base case and a selection of possible upgrades and what energy and greenhouse gas reductions we may expect from each. This document has proven invaluable and guided us through many decisions (which I will tell you more about, I promise).
WHITEHEAD RESIDENCE CONFIDENTIAL TO KOEHN/ROWLEY
Preliminary Hot 2000 modeling notes.
Monte Paulsen. Feb 21-24, 2013.
BASE CASE ASSUMPTIONS
The modeling exercise begins with a “base case” model. Often this is either the existing house, or the new house as planned. For this project, the “base case” is a bit of a hybrid. We consider components of the existing house that could be retained in the renovation, in conjunction with components of the new house if built to minimum specs. Here are some key assumptions of the base case:
— The WHITEHEAD base case is based on observations by Monte Paulsen (Feb 5 visit) and on plans provided by James Rowley. The base case assumes the basement, addition, and dormer will be built to the dimensions shown. (Interior floor = 2839 sf = 263.75 square meters.)
— The base case assumes that all existing exterior walls are retained where possible. These are modeled as: wood lap siding, ¾-inch exterior wood sheathing, 2×4 @ 16” centres filled with ½-pound spray foam (R-3.6/inch) , ½-inch interior sheathing, gypsum drywall (GDW) in some rooms.
— The base case assumes that new exterior walls are built to minimum standards: Wood lap, ½-inch plywood sheathing, 2×4 @ 16” centres w/roxul batt (R-4/inch, or R-14 nominal), air barrier, GDW.
— The base case assumes all wood-framed, single-pane windows are retained, and that new windows are also single-paned in wood frames. (As planned.)
James’ note: the windows are, in fact, double-paned, but Monte explained this doesn’t really make much difference to the calculations. 🙁
— The base case assumes both chimneys will be removed as part of raising the house, and none will be rebuilt during the initial renovation phase in order to conserve budget. (Per discussion on Feb 5.)
— The base case deviates from the plans provided in two significant areas. First, the base case assumes ICF forms are deemed too problematic for structural reasons. (Per discussion on Feb 5.) Instead, the base case assumes conventional concrete foundation walls, exposed to the exterior, framed with 2×4 @16 withy R-14 batt, GDW. The based case assumes 2” EPS foam underslab.
— The second significant deviation involves the way the upper ceiling is framed and insulated. The plans call for two distinct methods in a small attic: Kneewall and main floor ceiling insulation to the West, but cathedral ceiling insulation to the East. This is a problematic approach for several reasons. The base case assumes that the entire attic will be rebuilt using the insulated cathedral ceiling method (eg, eave insulation rather than kneewall insulation). The base case assumes that all ceilings are to plan: 2×8 @ 16” with R-28 insulation
— The base case assumes a median airtightness of 5.5 ACH@50Pa. This is likely tighter than the house stands now. This is likely looser than any target that will be chosen.
— The base case assumes the oil furnace remains the primary heat source. The Hot 200 model assumes this oil furnace has an output capacity in the range of 46,000 btu/hr and is operating at about 71% steady state efficiency. The base case assumes a 50-gallon (US) electric resistance DHW heater.
BASE CASE PROJECTIONS
Using these assumptions, Hot 2000 projects: EnerGuide = 63
Design Heat Loss (at 15.8F) = 46,000 BTU/hr.
Est. Annual Space and DHW energy consumption = 130,850 MJ = 36,347 kWh
(That’s about 137 kWh/m2)
Est. annual GHG emissions = 16 tonnes/year
UPGRADE CASE #1: ASHP
This upgrade case considers the sole effect of changing the heating source from the oil furnace to air-source heat pump (ASHP):
EnerGuide = 81.
Est. Annual Space and DHW energy consumption = 43,296 MJ = 12,026 kWh
(About 46 kWh/m2) .
This dramatic one-item upgrade case is presented merely to illustrate an underlying point: The selection of a heat source will influence the energy efficiency of this home more than any other single decision.
In this climate region, nothing is as cost-effective as a high-performance ASHP with a low balance point. These ASHPs operate close to 300% efficient in our climate. Compare that to 100% for AC baseboards, 95% for condensing gas boilers, or about 70% for most oil-fired furnaces.
I recommend planning for a high-performance ASHP from the outset, regardless of other decisions.
With this in mind, I suggest for consideration, one possible approach to budgeting for this project: First, determine what you can afford and mark it down by 25% for contingencies. Second, determine whether you want to continue with forced-air heat distribution or convert to radiant floors and/or radiators. (More on that below.) Third, determine an accurate price for a high-efficiency ASHP (eg, Mitsubishi or Daikun) and distribution system. Fourth, once money for this mechanical system is set aside, use the remainder of your budget to make the most aggressive envelope upgrades you are able to afford.
UPGRADE CASE #2: WINDOWS
This upgrade case asks: How much of a difference do the single-pane windows make?
For the sake of this exercise, ALL windows in the house are replaced with common commercial units similar to Energy Star Zone C. These would include vinyl frames, double-paned glass, Low-E coatings (.2/hard), Argon gas in 13mm cavities, insulated spacers, and tight-sealing casement openings.
Under these conditions, projected ratings for the Whitehead house are as follows:
EnerGuide = 72
Design Heat Loss (at 15.8F) = 34,798 BTU/hr.
Est. Annual Space and DHW energy consumption = 89,400 MJ = 24,833 kWh
(That’s about 94 kWh/m2)
So we see that windows make a large difference to heat loss. At the same time, we understand that a significant portion of the heritage value of this house is related to these windows. Therefore, one of the most complicated decisions you will have to make is to choose which windows to upgrade, and how.
I recommend seeking expert advice on this question, sooner rather than later.
First, I suggest hiring a heritage consultant to give you specific advice about the heritage value of these windows. Are they the originals? Or have they been rebuilt? Is the paint scheme appropriate? What thermal upgrades would a heritage consultant consider acceptable?
Second, I suggest you call Keri Briggs at Vintage Woodworks. (250-386-5354 x154) Tell her I’m doing the energy modeling on your project and that I suggested you get a sense of the options and costs for your home. Who you choose to do the work will be up to you: I’m suggesting Keri (or someone on her team) will do a good job of walking you through the options.
In the upgrade models below, I will make certain assumptions about your windows. These will be made for the sake of outlining various options for discussion. Please understand that I am not a heritage window expert and I am not advocating one approach or another to your windows. Rather, I am recommending you seek professional advice and comprehensive price options.
UPGRADE CASE #3: ENVELOPE UPGRADES
This upgrade case model demonstrates the effectiveness of a range of “opportunistic envelope upgrades.” Together, these raise the Base Case to EnerGuide 75 (with the oil furnace).
The approach to this upgrade model is as follows: “The basement is being entirely rebuilt. The back wall is being rebuilt. The upper floor is being rebuilt. Since we’re rebuilding most of these components anyway, what efficiency gains could be achieved through a series of framing-and-insulation upgrades.”
The upgrades described here represent materials and skills at the high-end of normal construction practice. These do not involve exotic materials or building techniques.
FOUNDATION — First and foremost, you need to decide if there’s a way to affordably use ICFs. I don’t see one. They add three to five inches to the outside thickness. If you were adding insulation to the outside of the house, this would be no problem. But you are trying to preserve the heritage exterior. So, from a conceptual viewpoint, I think we may want to think about putting any and all additional insulation toward the interior, on all levels.
Stephen J Cote-Rolvink, the Maple Ridge building official who participated in the Now House meeting, would be a great person to talk to about this issue. I suggest you ask him what he thinks, and also ask who he’d hire as an affordable local structural engineer.
So, if you’re going to build a conventional foundation, what’s the most cost effective way to insulate it?
Consider adding a “U” of foam insulation that runs down the wall, under the slab, and back up the opposite wall. This arrangement separates the slab from the wall, so the slab can work as thermal mass inside the envelope.
The upgrade model assumes six inches of EPS foam (white Styrofoam) under the slab (R-24) and two inches of XTPS (pink or blue foam) along the perimeter of the concrete (R-12). Inside the XTPS, the model assumes a 2×4 @ 24” wall with R-14 batt (eg, Roxul) insulation and GDW.
The header area above the (full-height) concrete foundation wall is sprayed with ½-pound foam insulation (eg, Icynene) to R-24 depth. This will help create an airtight seal between the XTPS and the floor above.
Spray the exposed ceiling in the rear (under the porch) with two-pound foam to increase insulation.
FOUNDATION WINDOWS & DOOR — Foundation windows modeled preserve the shape and paintabiliy of the existing wood, but are built of fibreglass frames, double-glazed, Low-E and Argon, insulated spacers, hinged. Door is fibreglass polyurethane core; pay close attention to air sealing all four sides.
HERITAGE FRONT WALLS — This upgrade case assumes no changes to the exterior heritage front walls in the sitting and living rooms. Repair the missing sections of spray foam.
MAIN FLOOR WALLS — This case assumes all other main floor walls are thickened to six-inch construction and insulated as close to nominal R-22 as the construction allows.
MAIN FLOOR WINDOWS — Case assumes rebuild of all first-storey windows to wood frames, 2x low-e glass.
HEADER — Spray to R-24 or more foam (Icynene). Focus on air sealing after reconstruction.
UPPER STOREY WALLS — The walls of the new upper story will wind up being largely rebuilt. Also, they will wind up with quite complicated framing, once the existing framing and the dormer framing are considered. Achieving good airsealing will be challenging.
I recommend framing these (mostly new) walls to between 2×6 and 2×8 depths (7.25”). This will be done in a variety of ways. Either spray the entire cavity to R-24. (Alternately, to save some money, insert batt insulation along the outside half and spray the inside three inches.) The spray foam is part of getting a good airseal along these complicated wall forms.
I strongly recommend rebuilding the kneewall and cathedral ceiling area on the West side of the attic to conform to the construction and insulation stye being employed on the East side of the attic. Specifically, reframe the roof and insulate along the underside of the roof deck. This is a smaller and less convoluted surface than insulating along the ceiling, up the kneewall, and along the thin cathedral ceiling. (See sketch.)
UPPER STOREY WINDOWS — Upgrade case assumes upstairs windows preserve the shape and paintabiliy of the existing wood, but are built of fibreglass frames, double-glazed, Low-E and Argon, insulated spacers, hinged. Door is fibreglass polyurethane core; pay close attention to air sealing all four sides
DOORS — Retain heritage wood doors. Rebuild doorlights to double-paned.
CEILINGS — The plans call for a set of cathedral ceilings framed with 2×8 @16 and insulated to R-28. I recommend thickening all of this framing to 2×12 and widening to 24” OC where possible. Insulation to R-40, either with roxul batt and an excellent air barrier, or with a “hot roof” application of 1/2-pound spray foam.
UPGRADE CASE #3 PROJECTIONS
EnerGuide = 75
Design Heat Loss (at 15.8F) = 24,400 BTU/hr.
UPGRADE CASE #4: ENVELOPE PLUS MECHANICAL
This upgrade case considers the effects of adding a series of off-the-shelf high-performance mechanical systems to the envelope upgrades described in case #3.
DRAIN WATER HEAT RECOVERY — Two four-foot sections.
HEAT PUMP WATER HEATER — Single-unit type, ducted through outer wall.
HEAT RECOVERY VENTILATOR — Dedicated low-volume ductwork. Ave 65% efficient.
IMPROVED AIRTIGHTNESS — Target 3.5 ACH@50Pa. (Hi end of ave new const.)
AIR-SOURCE HEAT PUMP — Mitsubishi Zuba-Central modeled. (See flyer.) This is a high-efficiency heat pump that powers a central air handler. This would readily replace your existing furnace, while retaining forced-air heat distribution. Under this scenario, I would recommend rebuilding your forced air duct network entirely. This is likely cheaper than installing radiant floors, and it allows more options for preserving heritage flooring. (Though you will likely wind up installing new subfloors regardless.)
UPGRADE CASE #4 PROJECTIONS
Using these assumptions, Hot 2000 projects: EnerGuide = 89
Design Heat Loss (at 15.8F) = 24,400 BTU/hr.
Est. Annual Space and DHW energy consumption = 14,829 MJ 4,120 kWh
Sometimes, I look around and wonder if anyone else is doing what we’re doing. When I meet people who are, it’s really heartening. I want to be that for you. Now that you have read this blog, anytime that you find yourself asking, “is anyone really taking aggressive action to reduce their personal carbon footprint?” you can say, “yes! James and Leanne are going at it whole hog!”
To recap, why are we spending so much time, energy and money making our house last forever? It’s not much different from why people buy those nice granite countertops–because we want to.