On this page are products and practices which we recommend as the most advanced in the industry. We do not provide most of these products and services, but hope this is useful to you as a resource, and welcome suggestions as well.
Deconstruction is an alternative to conventional demolition, which involves the disassembly of the structure into component parts for reuse and resale, rather than smashing of it for disposal. Often up to 85% of the structure's materials can be recovered for reuse.
Several companies do deconstruction in the Puget Sound area, and thousands of tons of usable building materials have been diverted from landfills over the past several years. These materials go to markets both in the U.S. and abroad. In the U.S., materials are shipped to deconstructors' warehouses or those of a partnering organization for sales and distribution to the public. Some materials are used as raw material by furniture, cabinet and flooring manufacturers. Larger dimensional lumber is shipped to mills that resurface and cut the lumber for reuse in homes and commercial buildings. The older the source building, the more likely that it will be made of very fine old-growth lumber, with tight grain and high strength.
Contractors and building owners who hire deconstructors are usually pleased with the process, and with the safety programs and training. Jobs are usually started and completed on time and on budget. Often jobs must be scheduled three months in advance, however. The City of Seattle is now considering the issuance of demolition permits earlier than other permits, in order to allow for the deconstruction process. (Feb 08)
Tax deductions are available for every private building owner who uses deconstruction, which are not available for traditional demolition. These deductions can be substantial -- sometimes large enough to actually pay for the costs of deconstruction. The chart on the top-right shows actual deconstruction jobs and the tax donation value received by the homeowners. These amounts are dependent upon many variables and should not be used for your specific application.
The example on the bottom-right is a composite based on actual jobs and is offered here to make an economic comparison between deconstruction and demolition. This composite is a single story, 2200 square foot house plus garage, with 3 bedrooms, 2 baths, raised foundation, composite shingles, single-paned windows, carpeting, hardwood floors, and a 12 x 40 wood deck. The costs do not include removal of concrete slabs, sidewalks, foundations or asphalt, but do include the site being left in a rake-clean condition (no debris).
In the machine demolition scenario, the owner pays $10,100, but in the deconstruction scenario, the building owner not only offsets the cost of demolition, but receives $4,702 in after-tax benefit. In other words, the owner would be financially better off to the tune of $14,802 ($4,702 received in tax benefits vs. paying $10,100 in demolition costs). Of course, figures vary depending on location, age and condition of the home and materials, topography, type of siding and interior walls, distance from the warehouse, landfill rates, etc. Still, the economics almost always favor deconstruction over demolition. Contact your favorite deconstructor for specifics.
Deconstructors that we know of are Earthwise, ReStore, Second Use, and The Reuse People. Also, concrete can be recycled for a small fee. For details, please see Concrete 201, under "How Green...". To find where to recycle just about anything, check out King County's reference.
Heat and Cool
Hydronic piping in floors is experiencing broad adoption these days because it matches the way people need heat. Some are even finding that when hydronic piping is installed in lower floors, it is not strictly needed in upper floors due to the extremely effective insulation of ICF. However experience shows that on the coldest days if there is no hydronic upstairs, the corners of rooms can be cold, so we recommend a hydronic line around the perimeter upstairs to compensate. This is all that's needed with ICF walls and good roof insulation. Also to let you know, there are hydronic underlayment products which incorporate an aluminum layer to spread the heat over a larger area. While an appealing idea, a university study has found that it makes no difference in efficiency.
ICF structures are so airtight that if the best construction practices are followed, air-changes per hour can be below .01; a typical stick-built home can test over .5 air-changes per hour. Uncontrolled air leakage is the number one enemy of energy efficiency in a home, responsible for up to 40 percent of energy loss, nationally. But the only thing preventing a blower-door test from pulling a vacuum in a well-built ICF home is the windows and doors! The corollary to this is that air-tightness also means that over time there will be a buildup of indoor air pollutants like carbon dioxide, VOCs, and odors, so:The Energy Recovery Ventilator
Hydronic is an excellent means of warmth, but it doesn't do the whole job. The Energy Recovery Ventilator is a ventilation system which provides fresh air and improved climate control, while also saving energy by reducing the heating (or cooling) requirements. It does this by employing a counter-flow heat exchanger between the inbound and outbound air flow. A Heat Recovery Ventilator (HRV), as the name implies, recovers the heat energy in the exhaust air, and transfers it to fresh air as it enters the building. An Energy Recovery Ventilator (ERV) is closely related, however an ERV also allows you to control the humidity level of the intake air, which is helpful in keeping out humidity on rainy days, and keep it in during Winter. Indoor humidity can be controlled with an ERV, and this comes at additional cost, but we suggest it is well worth it.
An ERV in the home would normally be set to come on for five minutes every hour, and best practice would be for it to come on whenever the kitchen light is on (humidity, cooking odors), whenever a bathroom light is on, and whenever carbon dioxide rises above a set level (having a party). This will ensure outdoor fresh air indoors all the time, without the loss of the energy it took to warm or cool the house, complimenting the hydronic system. Intakes need only be in the kitchen and bathrooms, and outlets should be in most other rooms. Often an ERV comes with the option of a water coil, for supplemental heat or cool of the living space; we recommend that you either get this, or get an addon water coil with drip pan (for chilled water) from First Company or the like. Some very good brands of ERV/HRV are UltimateAir, Venmar, and RenewAire.Heat and Cool Source
Hydronics has been used in large-scale commercial buildings such as high-rise and campus facilities for decades, because it is an efficient method of heat distribution, and compliments the heat-gradient of us humans. There are as many ways to heat and cool the water as there are mechanical engineers, but for heat we highly recommend solar, supplemented with a tankless hot water heater. A condensing boiler is probably overkill in an ICF home; many condensing boilers heat domestic water too, but do you want it running during the Summer? No, a properly sized and designed evac-tube solar system with a stainless-steel storage tank in a drain-back configuration and supplemented with tankless heater, should cover most if not all your domestic water and space-heating needs in western Washington.
For cooling, either an absorption water chiller driven by solar hot water to chill your ERV's water coil or a ground-source heat pump system, if the cost is not out of range. The ground-source heat pump system is usually eliminated due to the cost of drilling a deep well, but there is a method of burying the lines in trenches as helical loops, if there is enough surface area on the property. Anyway, solar is more appealing. Some very good brands of solar collectors are AMK, Apricus, and Thermomax. Beware, off-brand Chinese evac-tube collectors have a reputation for leaking. Honeywell and ZCP make good controls, and Grundfos makes excellent pumps.
So, the best of all worlds would be hydronic to heat in Winter, and chilled-water through the ERV to cool in Summer, although in an ICF home cooling will almost never be needed in western Washington. Some good brands of hydronic equipment are Rehau, Uponor (form. Wirsbo), and Watts. In a tankless or condensing boiler, be sure to look for one that is 'modulating', so it doesn't just come on full blast. Some good tankless brands are Bosch, Takagi, and Seisco (electric), and a good condensing boiler is Viessmann.
For a long time we have recommended isocyanene closed-cell spray-foam insulation in the attic rafters as the best way to insulate and seal an ICF residential or commercial structure, air-tight. However there is a revolutionary new form of insulation called Mineral Foam, which is essentially a concrete mousse, filled with millions of microscopic air bubbles that puff it up to a shaving-cream like consistency. Mineral foam offers all the benefits of spray-foam insulation plus it is fireproof, and it is inert with no off-gassing
It hardens and has an R-value of 3.9 per inch, although its true benefit is much higher as it offers not just insulative resistance and airtight sealing as with expanding foam, but also it has thermal mass unparalleled by any insulation on the market today. Very ICF-like. The value of thermal mass is described on our Insulation 201 page.
We suggest that mineral foam insulation be applied into roof rafters, which fills all gaps and glues all structural members together for added strength which is needed during seismic events. It adheres on contact, forming an airtight seal eliminating infiltration currents --the number one source of heat loss-- helping maintain a comfortable, constant temperature. When applied in the rafters down to the ICF walls, it encloses and seals the building airtight and renders the attic a 'conditioned space', conserving the energy normally lost by attic ducting and leaks through ceilings, and allowing you to put ducting, ERV, air handlers, etc up there. Your ICF home or office will be so tight that it will qualify in this respect for the highest independently-verified certification standards, such as LEED Platinum, EnergyStar, and BuiltGreen five star. Did you know that there's a $2,000 federal tax credit for builders if you get an EnergyStar rating for your building?
Our old recommendation was soy-based isocyanene closed-cell foam, which resistance to heat transfer (R-Value) is far superior to blown-in cellulose or fiberglass batts having the same rating, because closed-cell foam does not allow air convection currents through the insulation. High R-Value combined with an airtight seal, result in dramatic energy savings. While fibrous batts provide minimal resistance to air infiltration and exfiltration, isocyanene foam insulation completely fills cracks, crevices and penetrations in the building envelope when properly applied, creating an airtight seal. Limitations of closed-cell foam though are that it can be applied only to a maximum of 3" thick because of fire and smoke generation; plus it possesses zero thermal mass. Mineral foam has no such limitation on the thickness that can be applied, as it is fire-proof! It will not smoke at all upon direct contact with flame, and in fact Air-Krete is rated as a four-hour firewall in the State of Connecticut. (as opposed to the 15 minute firewall of a stick-built home)
This high performance insulation and climate isolator also enables you to build stronger structures. Because of its ability to fully fill the structure and add rigidity, forming a solid bun between rafters, the roof becomes more stiff. Along with the natural sealing characteristics and thermal inertia of mineral foam comes the added benefit of noise reduction: it helps to block exterior sounds such as automobiles, wind, airplanes and any other outside disturbances, and does not echo like other foams, giving you a remarkably quiet building. Mineral foam has been used in many sound studios and home theaters for acoustic isolation.
Mineral foam costs about the same as isocyanene foam, which is more than batt insulation (~3x), but then it pays for itself within a few years because it does more than one job:
Most of these attributes are not available with any other insulation method. It pays for itself and then pays a dividend year after year thereafter, as there is no degradation in its performance as with fiberglass, cellulose, rock-wool or natural fiber insulations... it is concrete, after all. And unlike other methods, mineral foam does not emit dust, fibers, or chemical vapors/VOCs into the air.
We do not sell or install mineral foam, but are very enthusiastic about it. The licensed Air-Krete applicator for the Puget Sound area is BioIntegra.
Q: What do Seattlites call two straight days of rain?
A: A weekend!
Rainwater catchment is an idea that people have been trying to do on their own, but in order for it to work well a designed system is generally required. Rain is collected as runoff from a roof which is of impervious material like metal, plastic, or cement-fiber shingle. It should not be an asphalt-based roof or one which can harbor algae and other organisms. This runoff is directed into an underground holding tank for storage, which can be anywhere from 200 to 1,000 gallons, depending on how much it rains and how adverse you are to using City water. Much more storage though, and you risk the water going skunky.
Municipal ordinances prohibit using runoff water for human consumption, which includes use for showers and laundry, but it can be used for landscape irrigation and commode flush -- amongst the highest volume uses of water in a household. So a turbine (well) pump is immersed in the storage tank, and dedicated piping is run to each commode, hose bib, and sprinkler supply; the pump senses a drop in water pressure (demand) and automatically turns on, providing pressure. An expansion tank in the circuit provides buffering. Experience with rainwater catchment in the Australian Outback and Texas shows that the tank water can sit indefinitely without water treatment, as long as the incoming water is clean, it gets no Sun, and annual checks are made.Heating
It has been hard for some of us to get used to the idea, but the objective truth is that tankless water heaters are much more efficient, and tank-type water heaters are less. I remember tankless water heaters when I lived in Europe in the '70's (Carl), and they have been used much longer than that.
Today tankless heaters are instant-on and up to 95% efficient, converting up to 95% of input energy into usable hot water. Amazing. If gas is available, a gas-type heater is preferable to an electric one for reasons of energy cost, although gas-type heaters are best when installed as a house-wide unit rather than having one under each sink.
Some people now are installing hot water circulating systems, which give nearly instant hot water at every tap and eliminate the need to run the water for it to get hot. All that's involved is running a pipe from the far end of the hot water system back to the heater, and adding a circulating pump. Needless to say, all hot water pipes should be insulated; they usually aren't. The circulating pump can be activated with a motion sensor (someone enters the bathroom), or simply when the bathroom or kitchen light comes on.
Solar hot water has come a long way. There are many choices and much confusion, but we recommend a 'drain-back' system with evacuated-tube collectors. Evacuated-tube collectors are the most advanced, and are a borosilicate ('pyrex') glass tube ~3" in diameter and ~6' long, with a vacuum pulled for insulation, and a media tube running through the center. These collect Sun as it arcs almost all the way across the sky, even on indirect Sun days like we have in western Washington, and on bright days can get water above boiling. An insulated stainless water storage tank is in the basement or garage, and serves as the heat reservoir. When the collector temperature is higher than the tank temperature, a pump comes on circulating water through the collectors; when the pump is off, the water drains from the collectors back into the tank by gravity, eliminating possibility of freezing and the need to add toxic antifreeze. Inside the tank are a few copper loops of the domestic water line, so the hot tank water preheats the domestic hot water, reducing the need for the heater to come on. Simple and reliable, and another step toward the Zero Energy Home.
Needless to say, such a Solar hot water system could be integrated with your hydronic space-heating system as well, with some measures like a larger water reservoir and more collectors. Optionally you could add a heat stockpile, to store heat collected in Summer, for use in Winter. This would be a large underground box, well-insulated (made of ICF), with hydronic piping coiled through layers and layers of dirt or gravel. Save that boiling Summer water heat for a time when it can be put to better use.
Also you should know about a device which recaptures the heat from water going down the drain. It is a replacement for 2' to 6' of the bathtub drain, which has a pressurized water-line wrapped around it in loops. So as the shower is used and hot water goes down the drain though the device, the heat is picked up by the coiled water lines right before they reach the shower tap. Thus cold water to the shower is warmed by the drainwater, reducing the need for hot water. BuiltGreen can advise. These devices tend to be spendy, although prices are now coming down.
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