Posts Tagged ‘Water Efficiency’

Using Less Water in the Garden

February 27th, 2012
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Many of us have childhood memories playing outside during warm weather and getting caught in the stream of water as our parents fed the garden with the hose. It may have been fun to catch a few drops while the tomatoes were being drenched but overall it wasn’t efficient water usage.

 

With spring just around the corner gardeners are already planning out logistics for the new growing season and water efficiency is something that’s high on their agenda.

 

After all, some regions of North America are experiencing drought like conditions and water bills have gone up. Rather than cut back on prospective crops many gardeners want solutions.

That being the case here are a few tips for conserving vital water resources without jeopardizing a successful growing season:

 

Low-water plants

One way to save water is consider the types of plants and vegetation being grown as needs vary. For example, certain varieties of vegetables like some cucumbers need more water; things like squash need less. Certain lawns need to be fed very often; plants like lavender and rosemary can manage on less.

 

This isn’t to say an avid gardener should replace all plants that drink a lot with lower maintenance species. However it’s something to consider when choosing new additions for the garden or when planning to overhaul the landscaping.

 

In many respects it can be a major upgrade and excitingly new botanical adventure.

 

 

Water early

Once you’ve sorted out the kinds of plants it’s important to know the best time for feeding. For instance watering the garden during the middle of the day isn’t ideal because it’s the hottest hour and a large percentage of that water will simply evaporate.

 

The best time to water plants is in the early morning hours when it will give roots strength to take on the midday heat.

 

If that doesn’t work out the late afternoon or early evening will suffice. Just remember that when watering close to dark or at night it’s preferable not to get leaves wet because lingering moisture invites fungi and nocturnal creatures like slugs that eat vegetation.

 

 

Target the roots:

Targeting roots is the key to efficient feeding but doing so requires a good delivery. As already mentioned hoses are probably not the best tool for this because even on the most sensitive setting water will land in other places too.

Instead, the hose should be employed as a means for transferring water from the home to feeders when plots are in the middle of the yard. These feeders, such as watering cans, could then be filled on site in place of having to carry gallons from the house.

It should be noted that even when a hose is not being employed some watering cans may not have the appropriate spout to deliver water directly to the base of plants. If necessary, try using a water bottle or something similar that can control the stream better.

Alternatively, a great way to target roots is through drip irrigation systems which use minute amounts of water. These have been used regularly in agricultural settings but can be found more and more in the average green thumb’s garden.

Jakob Barry is a home improvement journalist for Networx.com. He blogs for pros across the U.S. like  Memphis, TN plumbers.

 

John Bell’s Green Home — Host of World’s Greenest Homes Greens His Own Home

December 16th, 2011

John Bell’s Greenest Home. (photo courtesy of John Bell)

As the host of season 2 of The World’s Greenest Homes, John Bell traveled the world touring the world’s greenest homes, speaking to the owners, builders and designers about the homes and what made them decide to build more sustainable housing. The homeowners had built these homes to lead greener lifestyles and lower their carbon footprint. Clearly his work influenced his next move: after finishing season two of The World’s Greenest Homes, John and his family sold their large three storey home in a beautiful but somewhat isolated Toronto neighbourhood, to a home a little more than a stone’s throw to mid-town Yonge Street with all of its advantages. In the process they cut their home’s footprint in half, and probably their transportation footprint in half too.

The house John and his wife purchased was an old 1970s house on a cul-de-sac with single-paned windows, little insulation and plenty of air leaks. In fact when the energy auditor did the home’s audit pre-renovation, it came it at a leaky 7.7 air changes per hour and an Energuide rating of 33 out of a possible 100. In terms of what those numbers mean, according to the Office of Energy Efficiency, a home’s Energuide rating of 0-5o is an older, unrenovated (uninsulated) home. At the opposite end of the scale, an Energuide rating of 91-100 is an airtight home with proper ventilation that requires no extra heat source. The Air Change measurement measures the number of times the volume of air in the house is being replaced through leaks in the home’s envelope approximately.

 

The Bells added another 800 square feet to the home’s footprint while renovating the house. Even so, when the energy auditor tested the renovated home, the Energuide rating rose to 80, and the air changes per hour dropped to 1.59 ACH.

Given his experience on The World’s Greenest Homes, John noted that every homeowner he interviewed had the goal of decreasing their carbon footprint by building a well-insulated, low carbon footprint home. So like the green homeowners before him, John concentrated his efforts on his building envelope and improving his home’s energy efficiency.

John hired John Godden from Clearsphere to help him achieve his energy efficiency and green building goals. John Godden has been an active member of the green building realm way before it became the place to be in construction. His firm was one of the partners involved in building the EcoLogic Community in Newmarket, ON, the first LEED Platinum community built in Canada.

Power Pipe DWHR system

Building envelope: The ceilings have an R value of 41, the new construction 2×6 walls of the addition have an R value of 26, the older 2×4 walls, an R value of 22. All are insulated with Roxul batt and rigid board insulation. Roxul is a locally produced mineral-wool-based insulation with a high recycled content that is also a good fire retardant and noise damper.  The basement floor and below grade basement walls were insulated with Roxul Drainboard with an R value of 10, and below grade walls have an R value of 32 as they have additional batt insulation inside the house.  Roxul batt and rigid board insulating products were used for most of the insulation work. There were spots in the house, however, where the best insulation was sprayfoam, so he used Icynene, a cellulose-based product.

Ridley Windows and Doors, sliding glass door to backyard

Windows are from Ridley, aluminum-clad wood interior windows, double-glazed with a low-EQ coating that helps block strong sun rays and heat in the summer so the air conditioning unit doesn’t have to work as hard.

Phillips LED lights. 7 Watts each, $12 at Home Depot

HVAC: The system is a 98% efficient boiler-fan coil system combined with duct work provided by Airmax Technologies. The boiler heats water for both domestic hot water, radiant heating. It works in conjunction with a forced air system.  John also had a Power Pipe installed which is a drainwater heat recovery (DWHR) system. DWHR can save you up to $125 per year depending on how much hot water you use (the more hot water used in the morning for showers, the more money it will save you). Radiant heating was installed in the basement to keep the floor warm, in front of the windows on the main floor at the front and back of the house, and in the two second floor bathrooms. A heat recovery ventilator was installed to capture heat from warm stale air, and to ventilate the now very tight house with warmed fresh air coming from outside.

 

Solar Air Panel Operation

Solar Sheat 1500G Air Panel. This is an interesting bit of new technology that John admits was installed more for the concept than for a specific return on investment. The way it works is, the panel sits on a south facing roof top where it can absorb the sun’s rays. Cool air is sucked up from inside the house, next it is warmed by the panel on the roof and blown back into the house via a vent. It has an optional solar PV panel used to operate the fan so that no additional electricity is needed. The single solar air panel provides enough heated air to heat 750 square feet, the approximate size of the second floor of John’s home. John said that with the tight envelope of the home, the heated air will help keep the second floor warmer even after the sun goes down, meaning the boiler. The system costs $16oo plus $2000 to install.

Brac Gray Water Holding tank

Dual flush toilets (tank hidden behind wall)

Water Efficiency: Another area John noted where green home builders were concerned was with water conservation. John became interested in gray water recycling, and in fact is now vice president of Greyter Water Systems a distributor of Brac Gray Water Systems. He installed a Brac gray water tank in his home and says that it provides more than enough water from showers to flush the toilets in his home. He also installed dual-flush toilets.

Green technologies: John figures that during the renovation, he spent an additional $28,000 on green technologies, including $10,000 for solar panels to be part of Ontario’s microFIT program. The energy upgrades John made will save him $4000 per year in energy costs vs. his previous bills, so his payback point comes in at around 7 years and that’s assuming energy prices stay at 2011 levels — which they won’t. The longward trend for energy pricing is definitely upwards.

In the end, John is aiming for Silver certification level of LEED Canada for Homes and will likely achieve it.

 

 

 

 

 

Tankless Hot Water Systems — Benefits and Drawbacks

May 10th, 2011

I’ve always been on the fence about tankless hot water, or “on-demand”, and whether it’s worth my while. The biggest advantage is that it can save a significant amount of money and CO2 output. In fact, Sears Canada has this really neat little calculator that shows just how much money and emissions you can save by switching to a tankless system. In my case, if I switch from my high efficiency hot water heater to a condensing tankless system I can save:

  • 921 kg CO2 emissions per year, 11,056 kg over the estimated 12 year life of the unit,
  • 484 m3 of natural gas or 5,811 m3 over the life of the unit,
  • $229.89 yearly or $2758.62 over the life of the unit.

These numbers are worth paying attention to. But I’d also heard that there were certain drawbacks to a tankless system that worried me. I figured it was time to get to the bottom of when a tankless system is a good idea, and when it isn’t. I contacted Aaron Goldwater of Goldwater Solar Services, a company that installs both solar hotwater and solar photovoltaic units. It turns out that solar hot water and  tankless systems complement each other, with each system optimizing the other.

I sent Aaron a whole list of questions, concerns and observations and he patiently answered with thorough, thoughtful responses. If you were wondering about tankless hot water and whether it’s right for your home, read on; Aaron clears up a lot of misconceptions about it, as well as pointing out the reality of a tankless system.

Cathy: A tankless hot water system cannot service a typical family of 4 or more, especially in the mornings when many showers might be being taken and the kitchen is in full swing. Same for night time if there are young children taking baths and the washing machine and dishwasher are on.

Aaron:
Different tankless water heaters have different flow rates and can supply different rates of hot water.  Some can produce 5 or more gallons per minute which is sufficient to run two showers at the same time.  You have to choose the right size tankless water heater for your household.  The amount of hot water (flow rate) that a tankless water heater can supply depends on the incoming temperature of the water and the set temperature of the tankless water heater.  The higher the temperature rise the lower the flow rate.  So in the winter when the city water comes into the house colder than in the summer, tankless water heaters will produce a lower flow rate.
As the difference in temperature decreases between the set temperature and the incoming temperature of the water, the flow rate increases.  Some tankless water heaters can produce as much as 9 gallons/minute if the difference in temperature is as low as 40 degrees F.  This could happen for example if the tankless is set for 105F and the incoming water temperature is 65F.  A solar hot water system will preheat the water before it reaches the tankless thereby increasing the flow rate of the tankless.
Having said that, water pressure is usually the real limiting factor for how many household facets you can run at the same time with hot water.  Many households don’t have sufficient water pressure to run 2 showers and do the dishes at the same time and this is NOT as a result of the tankless water heater not supplying enough hot water but a result of the size of the water pipes coming into the house.

Cathy: A cold water “sandwich” can occur if water is quickly turned off and on again in one part of the house (like the toilet flushing in older homes while someone is taking a shower).
Aaron:

In my experience and talking to my customers, the cold water sandwich doesn’t seem to be an issue.  I think the cold water sandwich occurs not when someone flushes the toilet but when a small section of the pipe has cold water trapped in it.  For example, lets say you take a show and then someone else in the house takes a shower 20 minutes later. The tankless water heater will take a few seconds to heat up again so although there’s warm water in the pipe after the tankless water heater, some cold water will pass through the tankless water heater before it gets warmed.  This would be eliminated with a solar water preheat system because the water would be warm or hot before entering the tankless.

Cathy: There is significant water wastage while the heating unit is warming up.
Aaron:

The one disadvantage of a TWH (lets use this acronym from now on) is that when the tap is turned on it takes about 10 to 20 seconds for the TWH to trigger and get hot enough so that the water passing through is at the set temperature.  Its this extra 10 to 15 seconds on top of the usual wait time that people notice and it can waste a bit of water.  Having said that, adding a solar water heater before the TWH as a preheat eliminates the added wait time most of the time because the water coming into the TWH is already warm or hot.  So the TWH doesn’t have to work as hard to heat up.

Cathy: An electric system uses too much electricity to off-set any real environmental or cost savings. A gas system (either propane or natural) is better.
Aaron:

An electric tankless water heater needs I believe a 100amp service and uses a lot of electricity to heat the water.  They also typcially have low capacity compared with gas units and can usually only run 1 shower.  Its not something we usually recommend unless there are no other options.

Cathy: Wouldn’t the optimum use of a solar hot water heater, combined with tankless, be during the middle of the day when the sun is shining? Is there any sort of storage unit for solar-heated hot water?
Aaron:

A solar water heater has a storage vessel (tank) usually next to the tankless water heater that heats up during the day and stores the heat for when its ready to be used.  Most solar tanks are insulated well and only lose about 1 degree F/hour once the sun goes down.  So if you shower in the morning, the water in the solar tank will still be hot.

Cathy: Are the “hybrid” systems a better bet for a large family? (ie., a tankless system that includes a small storage tank).
Aaron:

Not really.  A TWH with a small storage tank is usually only used to eliminate the wait time for HW.

Cathy: The pressure is often stronger than is needed for faucets in order for a larger capacity tankless system to work.
Aaron:

TWHs have a minimum flow rate to trigger the burner so if you only have the facet on partially the TWH might not trigger.

Cathy: Tankless systems are best suited for one and two person households.
Aaron:

Not true, because 20 people could live in one house and use a small tankless water heater.  As long as they shower one after the next, they will all have HW.

Cathy: I also wondered if you could pair a tankless system with a drain water heat recovery unit or a circulating pump on a timer.
Aaron:

A drain water heat recovery (DWHR) unit will increase the hot water flow rate of a tankless water heater because it increases the incoming temperature to the tankless and therefore lowers that differential I was talking about earlier.  For example, if the DWHR unit increases the city water temp by 10 degree F and the city water was coming in at 45F, that means that its now reaching the TWH at 55F instead of 45F.  Lets say the tankless is set at 110F.  Then that means instead of having to raise the temp by 65F it only has to raise it by 55F – this increase the hot water flow rate of the unit.

A recirc pump will keep the water running to the taps hot at all times so that when you turn on the tap the water is hot.
However, this is costly to install and will add more electricity consumption and gas consumption.

With a tankless water heater you can’t run out of hot water.  There is no storage of hot water. When you turn on the tap the tankless water heater is triggered and heats the water as it passes through it.  Therefore you can have the tap on 24/7 and never run out of hot water.  With a correctly sized tankless water heater you could run two showers all day a the same time.

Cathy: What’s the biggest obstacle to installing a tankless hot water system?
Aaron:

One of the biggest obstacles to having a tankless water heater installed can be installing the venting or exhaust from the unit. Because they produce a lot of heat in order to heat the water as it passes through the TWH the exhaust from the unit can be a very high temperature. Some tankless water heaters use stainless steel 5 or 6 inch venting pipes as a result of the high temperature. This type of TWH comes with a venting kit, however, any additional venting needed can be very expensive.

However, some units, called condensing tankless water heaters, recover the lost heat that would have travelled out the exhaust. This increases the efficiency of the tankless water heater to as high as 98% efficiency. These are the most efficient water heaters on the market. Also, since the exhaust is at a lower temperature these units use smaller PVC venting. PVC venting is cheaper and can be easier to run longer distances thereby making it easier to find a spot to vent the TWH.

The biggest issue with TWH for installation is that the units aren’t typically exhausted up a chimney. They are direct vent so the exhaust is typically run out the side of the house. Locating an appropriate spot for the venting can be tricky because the building code dictates how close the vent can be to different objects. For example, a vent cannot be within 3 ft of any door or window and it must be 1 ft above grade. It also has to be 2 ft from the property line. So if you have a very narrow passage between houses it may be difficult to find a spot to run the vent. A tankless installer should be able to determine if it can be installed within code.

Thanks for all your help Aaron!

For more information visit their webiste: http://www.goldwatersolar.com/

or, you can reach Aaron at:

Goldwater Solar Services
231 Fort York Blvd, Suite 716
Toronto, ON M5V 1B2
Canada

Phone and fax: +1-416-400-4747

Goldwater Services North
38 Algonquin Cres.,
Aurora, ON, L4G 3M5
647-520-4942

Blu Homes Prefab Home Manufacturer Comes to Canada

May 6th, 2011

Last Saturday I was invited to a seminar hosted by Blu Homes. I first read about Blu Homes on Treehugger when it was announced that the company had bought Michelle Kaufmann Designs. Michelle Kaufmann is a renowned architect who had her own design/build prefab green modular home site. With the stock market crash of 2008, which decimated the housing market in the US, Kaufmann’s firm was one of its many victims.

Blu Cutaway

Blu Homes designs and builds modern, green, modular home manufacturers. There are a few significant differences between Blu Homes and other modular home manufacturers: The frames are made out of steel and an entire module can be folded into a more compact form for easier transport. This ‘folding ability’ has several advantages over the traditional modular home.  For instance, fewer transport trucks are needed to ship modules (two can fit on one flat bed) which also significantly cuts down on the cost of shipping. In fact, one of their models can be shipped to a building site on just one truck.  Using fewer trucks means lower costs and less pollution from transportation. Because the shipments are smaller, they can travel up narrow, windy roads and can be installed in more challenging spaces.

Because of the folding technique, homes are all finished within the factory, meaning they can be reassembled on-site in significantly less time. In fact, Blu Homes sends in their trained assemblers to put the home in place and finish it. Maura told us that usually a house can be delivered, assembled and finished on site in about 10 days.

Another advantage to the folding technique is that modules can be up to 21 feet wide and 18 feet high once unfolded. A traditional modular home tends to have modules that are no wider than 8 or 9 feet with ceiling heights of the same measurement. The steel framed structure also gives the homes durability to withstand severe weather events including high wind areas, flood zones and even earthquake zones.

The Blu Home philosophy is all about providing a green prefabricated home with excellent design features. They have a team of architects (including Michelle Kaufmann) who have designed the current and upcoming model homes in their inventory.

There are many “standard” green features to these houses, in other words, features that are included in the cost of building the home.

 

Element Model

Smart Design: Homes are designed to feel big without being big, with open plans and high ceilings. They are also designed so that they can “grow with you.” In other words, if you only have the budget for a smaller unit, but anticipate the need for more space in the future (ie., a growing family, running your business from home, etc.), homes can be designed so that more pods (units) can be added later. Rooms are often designed with multiple uses in mind. Libraries can also be extra bedrooms, office spaces, play rooms, etc.

Orientation: Like any good green home design, Blu Homes will help you site the house so that passive solar gains are maximized and wind patterns are taken into account. In addition, included in their overall fees are basic deck designs and some landscaping design.

HVAC: Maura told us that they spent significant time perfecting the installation of radiant heat flooring so that it was a standard feature in all models. Standard are 93% efficient Viessman boilers in larger models and Embassey boilers in smaller models. HRVs or ERVs (heat/energy recovery ventilator) are also built in to every model. Note, central air conditioning is not included in homes because they are built for the most part without forced air (ducted) furnaces. However, Blu Homes will design a ducted home for you. In general though, the theory of a green home is that central air conditioning should not be necessary if the building envelope and positioning are done properly, particularly in a northern climate. Homes can come with mini-split (ductless) air conditioning units.

 

Origin Model, Interior

Building Envelope: The tighter the building envelope the smaller the heating and cooling system that’s needed, the less money you will spend heating your home. In this case, the building envelope consists of a combination of rigid foam insulation and eco fiberglass insulation in the walls. Walls are built with an R value of 24.5, Basement with R-19 or r-29 depending on if the basement or crawl space is conditioned. The roof is put together using SIPs for an R value of 38 or 45, depending on the model.

Windows: The windows are Anderson 400 series, which are high quality windows. They are double-glazed, with a low-e coating and filled with insulating argon gas to give a U-value of 0.31 (which is the equivalent of an R value of 3.22).

Material Use: In general, to have as low an impact as possible when building these homes, thought has gone into the selection of all materials. There is extensive recycled content used within the construction of the homes, and because they are built within a factory, there is 50-75% less material waste per home than homes constructed on-site.

Water Use: All toilets, showers and faucets are low flow, and there is the option of including a living roof (or green roof), and rain water catchment systems (additional charges for these systems).

Fresh air: A typical new home can off-gas up to 22 pounds of harmful volatile organic compounds into the air, and the off-gassing can continue for years. All Blu Homes are made with products with no off-gassing potential or mould-generating potential. Indoor paints and stains are zero-VOC, flooring choices consist of wood, tile, and other hard surfaces. Note: Because the foundation is the owner’s responsibility, you should discuss different mould prevention options with your site contractor.

 

Origin Media Room

Energy Efficiency: With energy use in mind, provided lighting is CFL and some LED where appropriate. All included appliances are Energy Star.

Home Models: There are currently 7 different models to choose from. Many of the models are available in a “mix and match” scenario where one kind of design fits with another. The current trend on larger pieces of land is to develop different “pods”, such as a main house with a separate guest house or art studio or retreat all on the same property.

What the client is reponsible for: First, you need to have a plot of land. If you’re not sure whether it’s suitable, Blu Homes will advise you on whether one of their models can be built on it. Secondly, you are responsible for hiring a site contractor to build the foundation, as well as to get all the necessary permits. Blu Homes will send the home plans to the contractor, but the contractor is responsible for the design and construction of the foundation, whether it’s a crawl space or full basement is left up to you. You are also responsible for landscaping and deck construction, but Blu Homes will help guide you. They will do a complete landscape design for you for an additional fee.

For more information, visit the Blu Homes website, or contact them directly using their contact form.

Origin Model after a snowstorm

Ontario GreenSpec’s Home Sweet Home Award Winners!

April 20th, 2011

On April 12th, Ontario GreenSpec hosted the second annual Home Sweet Home awards — a competition dedicated to promoting green home building practices in Ontario.

It’s heartening to see a growing number of builders and homeowners taking significant steps towards reducing greenhouse gas emissions in their buildings. This year Ontario GreenSpec had several different categories in order to distinguish between large tract home builders, smaller builders and renovations. Winners in each category are below.

Affordable Green Home

Affordable Green Home of the Year: Built on behalf of Habitat for Humanity in Peterborough by students from Fleming College, this house not only has all the “green” features you could imagine, it was built for $210,000. Some of the features are:

  • R35 structurally insulated straw bale home
  • water conservation: low flow faucets/shower heads throughout the house
  • Solar hot water panels
  • HRV and condensing furnace
  • many building products sourced from Ontario

Greenbilt House

Custom Home of the Year: The GreenBilt House in Oakville, Ontario was built to blend in with the neighbourhood, and built in the style of the old farmhouses from the area. What’s different about this house, however, is that it is built with “green features” taken into account. The house is:

  • a “pre-fabricated” home — ie., built in a factory which minimizes waste
  • 20% smaller than its neighbours
  • designed for passive solar and thermal mass absorption
  • heated and cooled using a  ground source heat pump (geo-thermal system)
  • on a fully permeable lot (including the grassy driveway) minimizing water run-off to the street
  • located close to public transit

Eaton Production Home

Production Home of the Year: Eaton Production Home. The purpose of this category is to show that one “green” success can be replicated on a larger scale.  The most unique feature of this home was the installation of a “whole house fan” — installed in the ceiling of the upper-most floor, this fan is powerful enough to suck all of the hot air in a home out within 30 minutes, reducing the need for air conditioning. Other features include:

  • Foundation consists of insulated concrete forms reducing the amount of cement used while including insulation in one material,
  • Water-saving features such as a rainwater cistern to feed toilets and landscaping, low flow faucets and showerheads, 3L toilets,
  • Permeable landscaping and drought resistant sod promote lower outdoor water use and less rainwater run-off to street,
  • Close to public transit.

The Rosedale House

Renovated Home of the Year: The Rosedale House — a complete gut and remodel of a 90 year old home within the original footings of the building. The project’s primary focus was on sealing the home and increasing insulation levels, however there were other initiatives taken as well:

  • Significant energy reduction by 85% compared with pre-renovation energy consumption numbers.
  • Repurposing of many of the home’s materials. Kitchen cabinets were reused, windows were not replaced.
  • Significant HVAC upgrades were made including installation of an ERV (energy recovery ventilator), efficient boiler and hotwater tank.
  • New, energy efficient appliances replaced old, energy consuming ones.
  • Low flow water fixtures and toilets
  • Near public transit.
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