Utility efficiency suggestions (Austin: sale, new home, water heater)

[balor123]

Originally Posted by CptnRn

Don't fool yourself. In winter my water usage has been as low as 5100 gallons per month. In summer when watering the yard it is in the range of 15,000 to 20,000 gallons per month, for a .20 acre site with 45% impervious cover. And that is with a concerted effort to water as little as possible but keep my lawn and plants healthy.

Ok point taken What should I ask the builder to think about? Drip irrigation was mentioned before. Is that something I can take care of later or does the builder need to do it? Other things that I've read: placing the sprinklers far from non-lawn and installing a rain sensor. It's supposed to be a control4 home so I'm hoping that I can find a simple wireless sensor to go along with it or, if internet connected, set it up to skip watering when the weather says it's going to rain.

[balor123]

Originally Posted by OpenD

Why not ask an expert? Personally I think the most exotic thing about it is the 30% tax credit and the $2,000 rebate if you're in Austin Energy area.

I'm not really building the home - they're building it and selling it to me. They're already building the home and it's taking them a while just to decide if tankless is even an option so I don't think something that's not a drop in replacement is going to fly with them. Keep in mind that part of the reason they're hesitant to do anything exotic is that if the deal goes sour then they need to be able to sell it to someone else and recoup the cost.

[scottsheehan026]

What is your future HOA's stance on Xeriscaping?

Xeriscaping - Wikipedia, the free encyclopedia

The other option is a full blown rain water collection system.

[balor123]

The HOA documents aren't finished yet so I haven't seen them. They are already landscaping with drought resistant native plants and grass however. My concern about rain water collection system is what the ROI is. In a previous post it didn't look all that good but maybe my calculations are wrong?

Also, what are some thoughts about hardwood in kitchen? Builder seems to be putting them in there. Should I ask for tile? It sort of flows with the family room so I'm not sure what the transition is going to look like.

[10scoachrick]

Originally Posted by balor123

Ok point taken What should I ask the builder to think about? Drip irrigation was mentioned before. Is that something I can take care of later or does the builder need to do it? Other things that I've read: placing the sprinklers far from non-lawn and installing a rain sensor. It's supposed to be a control4 home so I'm hoping that I can find a simple wireless sensor to go along with it or, if internet connected, set it up to skip watering when the weather says it's going to rain.

Not that we will ALWAYS be under watering restrictions(or maybe we WILL), but the only automatic watering option you have in much of the metro area is the ONE morning a week. And given the spotty nature of much of the rain events, the only way to be SURE it's raining outside is to send the dog out...If he comes back wet...it's raining! No way would I shut off my ONE morning of watering based on a FORECAST .

[OpenD]

Originally Posted by balor123

Well, I would get the rain water either way so it doesn't count How many days a year does it rain in Austin? Suppose it's a few times a month then that's about 30 times a year. Each time I might collect 55 gallons of water. At .3 cents/gallon that's a savings of only $6.50 a year. Maybe I can do better with a larger collection but you don't want the water sitting there for weeks unless you like mosquitos. Seems like it neither pays for itself nor the maintenance. It's not even clear that it helps the environment, as that water would have seeped into the ground otherwise and either been used by plants around my home or pumped by the city later.

Sorry, but you're way off. This is why it's important to actually do the math required.

Let's start with average rainfall, the last couple of years have been below average, but long term records show that Austin average 33" of rain per year, which is actually about average for the rest of the country. Part of the reason it doesn't seem that way is that Central Texas tends to get rainfaill in short intense bunches, separated by long dry spells.

Then we need to look at the collection area. This is not the surface area of the roof, but rather the footprint. It corresponds to the area on the ground covered by the roof. For ease of calculation let's use 1,000 square feet... small for a house by contemporary standards.

Then the efficiency of the collection system. You'll never achieve 100% because some always splashes out, but let's assume 90% gets to the tank or barrel.

Using the industry accepted formula for rain collection, 1" of rain on 1,000 sq ft = 623 gallons x 90% efficiency = 560 gals.

33" of rain = 18, 480 gals/yr. At .03/gal that's $554, or about 100 times what you calculated. And for only 1,000 sq ft of roof.

As for storing the collected water, the step up from rain barrels are recycled 330 gal poly tanks in a 4 x 4 x 4' steel cage, known as totes, which are available on Craig's list for $100-125 each.

It's actually quite easy to do, and the payback is quick. Plus being able to capture those quick rains we get to parse out as needed for thirsty trees and landscaping and gardens, rather than just have it all disappear down the storm drains, is a very good feeling.

Here's the link to the free handbook on Texas rainwater catchment: http://www.twdb.state.tx.us/publicat...3rdedition.pdf

[chuck_steak]

Originally Posted by OpenD

Sorry, but you're way off. This is why it's important to actually do the math required.

Let's start with average rainfall, the last couple of years have been below average, but long term records show that Austin average 33" of rain per year, which is actually about average for the rest of the country. Part of the reason it doesn't seem that way is that Central Texas tends to get rainfaill in short intense bunches, separated by long dry spells.

Then we need to look at the collection area. This is not the surface area of the roof, but rather the footprint. It corresponds to the area on the ground covered by the roof. For ease of calculation let's use 1,000 square feet... small for a house by contemporary standards.

Then the efficiency of the collection system. You'll never achieve 100% because some always splashes out, but let's assume 90% gets to the tank or barrel.

Using the industry accepted formula for rain collection, 1" of rain on 1,000 sq ft = 623 gallons x 90% efficiency = 560 gals.

33" of rain = 18, 480 gals/yr. At .03/gal that's $554, or about 100 times what you calculated. And for only 1,000 sq ft of roof.

As for storing the collected water, the step up from rain barrels are recycled 330 gal poly tanks in a 4 x 4 x 4' steel cage, known as totes, which are available on Craig's list for $100-125 each.

It's actually quite easy to do, and the payback is quick. Plus being able to capture those quick rains we get to parse out as needed for thirsty trees and landscaping and gardens, rather than just have it all disappear down the storm drains, is a very good feeling.

Here's the link to the free handbook on Texas rainwater catchment: http://www.twdb.state.tx.us/publicat...3rdedition.pdf

In Hawaii they have big metal tanks that everyone puts in their backyards for rain water collection instead of these poly tank barrels you are talking about. Anyway, the big metal tanks provide the yard and whole house with gray water. The only water residents buy is drinking water or they filter the gray water. It's pretty efficient, but the big metal tanks look ugly in the yards.

[scottsheehan026]

Well for starters when I said rain water collection I was not talking little 55 gal. poly tanks. I have just never seen the point in them. My yard sucks up over 2,000 gallons of water a week during the summer. 55 gallons just doesn't seam to be worth it. I was talking about a full blown rain water collection system some people use them these days when they don't want to drill a well. It costs about the same amount of money as a well and will supply the whole house with water even drinking water.

Just to give you an idea. IWS | Education | Rainwater harvesting, benefits, how much rain you can collect

[balor123]

Ok I can see the payoff for a larger tank - thanks for the analysis. I'm not sure that I want a large metal tank right now though in such a small yard. Should I ask the builder to just make it easy to build such a thing in the future if the cost of water becomes high enough? What would that involve? Perhaps a central drain for the gutters? Can this be integrated into the sprinkler system so that it preferentially uses the collected water?

[OpenD]

Originally Posted by chuck_steak

In Hawaii they have big metal tanks that everyone puts in their backyards for rain water collection instead of these poly tank barrels you are talking about. Anyway, the big metal tanks provide the yard and whole house with gray water. The only water residents buy is drinking water or they filter the gray water. It's pretty efficient, but the big metal tanks look ugly in the yards.

Not exactly. In Hawai'i people typically have tanks for rainwater, not grey water.

Funny thing is, I see more of those big metal tanks in Texas than I do in Hawai'i, because the metal tanks are fairly expensive and have an "agricultural" feel to them. Matter of fact, there's a "green" house on French Place (east of UT) that has won architectural awards and it has two 500-gallon corrugated metal tanks behind the house that would seem right at home out on the ranch. They use the rainwater they catch for landscape needs. If you want to be historically accurate, and have big bucks, you could build a limestone cistern like they used in this area in the early days. There's one at the Ladybird Wildlife Center and it's quite lovely.

On the Big Island, where 70% of the residents don't have access to county water supplies and wells are often impractical, the majority of houses have rainwater catchment and water storage of some kind. One of the most common (and cheapest) are "doughboy" type swimming pools with a cover. 10,000 gallons = $500 or so. If used for a potable water supply, however, they need a special "food grade" liner without the fungicide that standard liners contain.

Blow molded poly tanks are very common today in Hawai'i, typically colored dark green to inhibit algae growth, and buried at least part way into the ground to eliminate tipping in the event of an earthquake.

My point about the totes is simply that they are the obvious next step up from barrels, they're relatively inexpensive, and installation is within the range of a good DIYer.