Go Green
A Blog by WARM Training Center
A Blog by WARM Training Center
Jun 17th
What would it cost to build a water-catchment system for a home in SE Michigan? Code and other such issues will vary widely, but the actual construction costs are likely to be relatively uniform. I recently discovered that the city of Guelph, Ontario has done some great forward thinking work on encouraging rainwater catchment for their residents. I emailed the folks at Guelph, and they referred me to Ben Polley, a builder with Evolve Builders. Ben provided me with these excellent details about their cost and performance estimates.
Note that these figures include a good number of caveats about current unknowns and several costs that are not included, but they give us a good start on tracking down the overall costs. If you have additional data to round this picture out more, please let us know in the comments below.
Ben writes:
Hi Jacob,
In a former life, I used to perform work on the refrigeration systems in ice rinks in both Ann Arbor and Novi, MI. From that experience, I would expect that the pricing in formation below will be reasonably consistent with what you may find in Michigan too.
I have included below for your interest some excerpts of a design study we performed for a southern-Ontario project and the resulting price proposals. You will note that there are multiple items not considered in the quote that would yet further impact on final cost of construction though are difficult to assess unless aware of the full context of the work (eg. is it being performed at the same time as other excavating work in the example of a new home or is it a retrofit; whether one uses indoor storage tanks or an exterior buried cistern; which is more important, ensuring maximum utility of captured water or ensuring minimum number of “dry days” where water must be made up by other sources, etc).
So while these excerpts may also result in as many questions as it may answer, it should at least provide you with a ballpark starting figure for a couple of different types of system for a few different options of roof captured surface areas.
And then he provides those clips from the study:
Project Calculations:
| OPTION 1:
Active Storage Tank volume = 3200L |
||||||
| Performance parameter | Unit | House + Garage | House only | Half House + Garage | Half House only | Garage only |
| Catchment area | m2 | 254 | 200 | 154 | 100 | 54 |
| % of user demand met | % | 98% | 98% | 97% | 91% | 68% |
| % of rain utilized | % | 28% | 35% | 45% | 67% | 95% |
| Number of dry days | - | 7 | 9 | 14 | 37 | 137 |
| Number of overflow events | - | 74 | 64 | 51 | 28 | 3 |
| Volume of rainwater used | m3 | 52 | 51 | 51 | 48 | 36 |
| Volume of overflow | m3 | 135 | 96 | 63 | 25 | 2 |
| OPTION 2:
Active Storage Tank volume = 6400L |
||||||
| Performance parameter | Unit | House + Garage | House only | Half House + Garage | Half House only | Garage only |
| Catchment area | m2 | 254 | 200 | 154 | 100 | 54 |
| % of user demand met | % | 100% | 100% | 99% | 97% | 70% |
| % of rain utilized | % | 29% | 36% | 47% | 71% | 99% |
| Number of dry days | - | 1 | 1 | 2 | 13 | 126 |
| Number of overflow events | - | 74 | 63 | 49 | 24 | 1 |
| Volume of rainwater used | M3 | 53 | 52 | 52 | 51 | 37 |
| Volume of overflow | M3 | 134 | 95 | 61 | 22 | 0 |
% of user demand met – the percentage of all toilet flushes supplied solely by harvested and stored rainwater annually
% of rain utilized – the amount of water harvested with available tank storage capacity relative to overall amount of harvested water
Number of dry days – the number of days in a year where the cistern may not have sufficient water to handle the assumed usage
Number of overflow events – the number of rainfalls that fill storage tanks to capacity with additional water being sent to overflow
Volume of rainwater used – the annual volume of water harvested and stored in the tanks then used by the proposed fixtures
Volume of overflow – the annual volume of water harvested but sent to overflow after filling storage tanks to capacity
| EVOLVE RAINWATER HARVESTING SYSTEM | ||
| ITEM | INDOOR SYSTEM DESCRIPTION | OUTDOOR BURIED SYSTEM DESCRIPTION |
| Snow Capture | extra by others | extra by others |
| Winter Optimization | extra by others | extra by others |
| Coarse Prefiltration | Leaf Flusher at 6 downspouts, all on either | Leaf Flusher at 6 downspouts, all on either |
| the south side or north side only | the south side or north side only | |
| Transport of Water | yes, including above-grade penetrations | yes, including foundation penetrations |
| Cistern | 2 x 1300 litres | 1 x 6300 litres c/w 24″ riser |
| space required 6′-6″x7′-0″, 32″ door access | tank size 102″x72″x78″H, bury 24″ deep | |
| access path required along one short side | installed within 15′ of building | |
| minimum 24″ separation from septic lines | ||
| Overflow Protection | yes with floor drain by others | yes, via leaching pit or gravity drain |
| Fine Filtration | Yes | none |
| Calming Inlet | Yes | yes |
| Drought Protection | automatic | automatic |
| Water Treatment: micron filter | none required | none required |
| Water Treatment: carbon filter | none required | none required |
| Disinfection: UV disinfector | none required | none required |
| Plumbing to Fixtures | fixture feeds from RWH pump by others | fixture feeds from RWH pump by others |
| pump requires 3′-0″x3′-0″ adjacent to cistern | pump requires 3′-0″x3′-0″ adjacent to | |
| foundation penetrations | ||
| Electrical | extra by others | extra by others |
| Plumbing | fixture feeds & auto make-up extra by others | fixture feeds & auto make-up extra by others |
| Mains shutoff must be functional for retrofits | Mains shutoff must be functional for retrofits | |
| Site Management | n/a | site visit to ensure satisfactory excavation |
| Excavation & Fill | n/a | trenching, excavation & tank base fill extra |
| by others. Groundwater drainage if req’d | ||
| extra by others. | ||
| Price for above: | $8,980 +GST | $10,750 +GST |
| OPTIONAL | INDOOR SYSTEM | OUTDOOR SYSTEM |
| Indoor Tank Shade Cover | If open to sunlight, add $200 per tank | N/A |
| Aditional Tanks | Each 1300 litre tank, add $1350 | N/A |
| Larger Tank | N/A | Increase tank to 12,600 litres, add $2400 |
| Level Gauge | N/A | Add $300 |
[Update: Be sure to check out the comments for this post, as there are additional tech details and resource links.]
Jun 10th
I need a new roof (& am going DIY) & wondering if you have any advise on roofing materials /construction, etc….
- Chris, Waterford
Hey Chris,
I first started composing long lists of eco-roofing concepts, etc. Then I realized I just need to write back! Ha! So here’s my thoughts in a nutshell:
1) This is the time to make sure your insulation is up to snuff in your attic as it’s the easiest time to fix it. Code requires R30 at this point. If you can push it up closer to R50, that’s the recommendation for our climate.
2) Make sure that you’ve got proper venting, and that your venting includes baffles to ensure that air flow doesn’t ruin your insulation. See the picture below for an example. You can buy these cheap – though you can also make your own (speaking of DIY) with carboard. A properly vented roof will keep your home more comfortable in the summer, but it’ll also make the roof last a lot longer since heat kills shingles.
3) Go for lighter colors – they reflect more heat, making the roof last longer, as per above.
4) Shingles are still what most folks use. However, if you want some other options, you might consider a metal roof, which lasts a really long time (so you don’t have the same replacement costs down the road) and it’s better for water catchment and rainwater harvesting if you’re interested in that.
5) If you want to go further out on a limb, we can start talking recycled roofing material, solar shingles or a green roof, but I’m guessing that’s farther that you plan to go….
You can browse some product listings here and here and find a nice article on all of this, with more references: here.

Jun 3rd
Lead paint is a serious health hazard – and it’s notorious for being expensive to re-mediate. I’ve long been a fan of MT2′s EcoBond lead remediation paint. It’s not the encapsulating paint that many people use for lead abatement – where the lead is encased so that it won’t come loose. Rather, the Ecobond paint is high in phosphates which creates a chemical reaction with the lead in the pre-existing paint. This turns the lead into leadphosphate which is not hazardous in the same way.
Basically, you paint this on like a primer. Then you can either paint a new paint over that, knowing that the hazard is neutralized. Or, you paint this on and can then scrape the lead paint off without creating a hazard. I’ve used this material and it’s not pretty – you certainly wouldn’t want to leave it as a final coat. But that’s not what it’s intended for.
This makes better lead remediation cheaper and easier to tackle for home owners and rehab construction crews. With the new lead laws in place, I think it’s time for more people to know about this product. It can also help the burgeoning deconstruction world improve safety and cut costs.
Find more info here. You can also watch the video below. It’s produced by the manufacturer, so it’s a bit of a sales job, but I think it’s a product worth knowing about.
Jun 3rd
We’re looking for information on best practices for insulating a crawlspace on a 100 year old home in Northern Michigan.
- Jane, Boyne City
Many Michigan homes have crawlspaces. These offer some great opportunities for energy savings, but also real challenges for proper insulation installation and moisture management. In general, we have to make sure to create a continuous thermal barrier for the whole house, prevent moisture flow up from the ground and close off the venting. Despite the fact that many codes require vented crawlspaces, we now know that the venting leads to additional moisture and energy problems.
For best practices, I don’t think there’s a better guide than this one from the Building America program. For some additional research, I would also look at this article from Home Energy magazine – just keep in mind that this test was done in North Carolina, which has different climate concerns than Michigan. Also for additional research and information on how it intersects with codes, I’d recommend this article.
May 11th
We’re expanding our ministry and doing more green work including things like community gardens, kitchen renovations, etc. Can we pursue some kind of green certification for this?
- Dave, Madison Heights
Congrats on the new efforts – they sound great! While entire homes or neighborhoods can achieve a green certification, neither of these approaches seem relevant to the scale of work that you’re doing. From what you’ve described, I think the best route would be to tackle professional green certifications and training for the people who’ll be working on these projects. Here are a few options:
Those are the main green building certifications available. You also might want to consider just pursuing educational work for folks (without any particular certification) for the community garden work you’re doing. I would primarily recommend two resources for this:
And of course if you want a general introduction to Green Building course, WARM is always happy to provide that.
Apr 26th
Here’s a handy solar calculator to help determine if you can use/afford solar electricity (PV) on your home or business. It’s just a rough calculator, but puts out some nice details, including incentives, etc.