11.10.2006

How to Make a Green Building

These are the notes I took at the talk tonight by Marc Rosembaum, P.E. - Energysmiths – Meriden, NH. I think this makes the most sense as a sort of checklist to be asking administrators and architects as the college plans new building or renovation projects.

Why do we bother making environmentally friendly buildings?
1) Climate Change and 2) Future energy supply
We can begin by asking what the effects of our actions are on other people and the world. Its easy to forget how much we depend on the reliable natural cycles for our lives. We are really good at displacing the effects of our actions and industry is particularly good at it. For more on this theme check out www.minorheresies.com

We begin by mentioning Mathew Simmons. A lifelong republican and not a treehugger, he is an investment banker who began reading the Society of Oil Engineers publications to figure out what was going on. He found that five Saudi fields produce 90% of their supply, these are running out and require lots of new technology to continue to draw on their depleting fields. Furthermore, they have a strong incentive to say there is more oil than there actually is. Based on this, he predicts oil will be $200 a barrel by 2010 and he's so sure that he made a $5000 bet on it

Buildings are a third of our CO2 emissions in the US and residential homes almost half of that, and that figure is higher than most countries, even higher if we take transportation of people and goods to residential buildings

Reducing Commerical Energy Use – What can we do when we build buildings to make them very efficient and easy to maintain?
Envelope – super-insulate and make it airtight (and test it)- foam not thick enough and usually put in by masons who don't have as high standards. Commercial/institutional buildings leak more than residential buildings because the design is different for every one.
Daylighting – design buildings that don't need lights in the daytime
Lighting – make it efficient – don't put it where we don't need it
Cooling – load avoidance – shade glass, reduce internal gains like heat emitting appliances such as fridges.
Ventilation – enthalpy recovery ventilation – recover heat and moisture from waste air (summer and winter). Building code for ventilation in renovations has changed up and down since '70s energy crisis and it is a political issue, not a scientific one. We shouldn't look at the code to determine how much to ventilate (at least not any more than we have to, but instead look at long-term costs)
demand control – sense how many people are there to determine ventilation.
occupancy controlled – make a switch like the lights to turn on the ventilation.
ventilation wheeling – make the ventilation vary over the course of the day based on expected occupancy.
Mechanical distribution – hydronic (circulate water to control temperature instead of circulating and heating air) get the air into the building with the least impact. Reduction in building mechanical system pays for envelope (insulation) upgrades
Economizer buildings – operable windows, night flushing (open building at night to cool it down)
Identify key loads not common in normal buildings – exhaust hoods, dishwashers, refrigeration, etc and recover heat from unusual appliances light dishwashers.

Dartmouth case study – What have we learned from the projects Marc has taken on there?
The question is how much equipment we need in the building: we want about 20 cubic feet of air per person per minute and we find installed capacity at 80-100. This is overkill, but how do we avoid it?
We can recover heat from shower water. Students there use 50 gallons of water per day per student so lets re-use that heat from waste water.
Valence Convectors separate ventilation from heating/cooling. We shouldn't ask the ventilated air to do the work of the heating. These convectors should be separate because if we turn the thermostat up it increases ventilation, but we don't want more ventilation, just more heat/cool, so separate the two
Use radiant heating which has a low gain so it can't fluctuate much and be prone to human over-adjustment and it works very well the low yield profiles of geothermal heat pumps.
Membrane seal the roof – wrap the membrane around eaves and into walls. Then overlap the three layers of insulation and then test the airtightness. You can use a fog machine to test the seal so that its very obvious what you did or didn't do. This holds the builders obviously accountable to following the plans.

Renovations – Fixing what we already own
New, large, complex buildings are a very small percentage of national building stock so we need to figure out how to fix the stuff that we have. Easy things to change include insulation that can be added; replacing windows with more efficient ones; install GSHP (ground source heat pumps) which are not so complicated that they can't be added to a completed building. Inside mechanical renovations include ceiling mounted valence convectors which are pipes along edge of ceiling which can circulate hot or cold water. This creates a convection current for both hot or cold air. The system was tested in Dartmouth in dorms and the students haven't had any complaints

Lessons Learned
Show up - if you want things to go as you specify you need to show up and look. There has been a serious decrease in the skill of the workers because the trades are more complicated and the education culture among workers is weaker than it used to be. They have a harder job than they used to and less support for doing it.
Commission everything. A separate authority can make sure that the things that the builders say they have done were actually done. Some things are very easy to check
Match system complexity to owners ability to manage. Not every group of management can handle the complexity that top-notch buildings need. Smaller institutions don't have the staff time or staff expertise
The education happens at the client level. When you teach an institution what it wants in a building, they will learn to value that and stand up for themselves in the future. That is the most important aspect. From that point, you need to establish a system of engineers and firms who can share the risk of new designs and systems.

Cooperation between architects and engineers!
Look at building in a whole! Don't compartmentalize these individual issues!


Good projects don't happen by accident – it takes really good people to make it happen! The richest institutions in the world will talk about this and talk about this and talk about it, but where is the action? Why do these institutions reject offers to make hugely effective, money-saving changes? The decision making process is coming from the top down in determining what the priorities are! One person can make a huge change, but they make a change by finding the right people to do the job right. There's nothing in our way except the will of people do do things!

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