Next step for windows: vacuum insulated

In the foreground: Two models of vacuum insulation glass on the fair glastec06 in Düsseldorf, Germany

© ZAE Bayern, Würzburg

Vacuum instead of inert gases - with this technological development, glazing could take another great developmental stride. However, at 10 tonnes per square metre, the atmospheric pressure on evacuated flat glazing is immense. And for evacuated glazing, the same applies as for vacuum panels: only a lasting vacuum guarantees good thermal insulation. Now, this research project is to provide evidence that evacuated glazings with special functional layers are technically feasible for architecture.
It is estimated that the price of evacuated glazing will be comparable to that of triple glazing today, i.e. approximately 80 euros per m². 

For more info:
http://www.enob.info/en/new-technologies/projects/details/next-step-vacuum-insulation-glass/

Review: Maine built PH doors?

This is a review of entry swing doors made by Linwood Windows and Doors out of their shop in Rockwell, Maine. Linwood is a classic small shop with an interesting story and a good vision for high quality and performance. According the owner Richard Cohen, they bought a german tooling system for their windows and doors that are apparently certifiable in Germany for Passive House projects. The company is new and you can follow their progress on their blog.http://linwoodwindows.blogspot.com/

We ordered two entry doors for a 1840's farmhouse deep energy retrofit. It was important to have well insulated doors with high performance windows. Cohen said he could deliver doors with R5+ thermal performance but has not done any testing of the doors to provide any data for heat transfer or air leakage for their doors as a unit.

The design of the door is a rebated, double gasket European style door with classic raised panel and 1/2 glass. The raised panels have 1" of EPS foam with 3/4" of Doug Fir on either side.

The triple paned windows are quoted to have SHGC of .56 and Uvalue of .155 or R6.4. Richard thought that the whole door Uvalue would be better than the raised panel section but failed to explain how a 80"x36" door with 46% of the door only 2.5 inches of Doug Fir at ~ R3. I am assuming the glass has warm edge spacers.
 I would put the overall thermal performance of the door at around R4. This doesn't take into account the door frame or losses from air leakage.

We did install 1" polyiso foam around the frame to lessen the heat loss around the frame. The door frames and door construction are designed and built well.

A few complaints: we ordered the door without a finish and had to sand off a bit of glue stain and we had to take off the hardware to clean out the mortises of sawdust that was clogging the mechanism.  Everything fit well including the Zenit ball bearing adjustable hinges. Their were 4 hinges to secure the very heavy 3" door. We installed the door very easily and were happy with the squareness and ease of fitting.

 The biggest problem was the hardware.  Apparently the hardware company and Linnwood were not on the same page as the lock cylinders did not fit.  We got a replacement set that didn't fit and another that was stainless steel to match the oil rubber bronze handles.  So we sent those back and found the right fit and finish on our own.  The GU multipoint system was also a little futsy.  As I have used Hoppe systems as well, I would probably trade them out.

After it was all in, we inspected the air-tighness of the doors during a blower door test and found small leaks in both bottom corners of the door where the double gasket transitioned to the sweep sealed door bottom.  Minor, but considering I was able to completely seal all around conventional doors with off the shelf weatherization components, I would expect more from a $2300 door.

George of the Jungle

For anyone that wants an account of my recent vacation here is an accurate video documentation.

A look at the VbC Village Gathering 2012

SBF #26 Retesting Envelope Air Leakage

Our 2nd blower door test was conducted by Jacob Racusin, who is recently BPI certified and who did it as a part of the Yestermorrow Sustainable Design Certificate course with a group of students.
We got 770 cfm @ 50Pascal which gave us a new number for ACH50 of 1.8, improved from 2.1.  The difference was sealing off the chimney cleanout door, which was roughly 8"x12".
We noted a good leak at the mud room door from a warped door that used old barn boards that should have been kild dried, and  one on the bulkhead door.  These we knew about and could use attention.  There was also small leakage around the stove pipe connection to the chimney.

Fixing these might improve the leakage rate to 1.5ACH50. 

SBF#25 - The beauty of local stone

When Rock Solid Granite called about the slate we ordered, they were concerned about the fact that this stone was not "normal", and wanted to make sure it was ok to use.
Turns out to be the most beautiful slate countertop I have ever seen.

SolarFest 2012

 

http://www.solarfest.org/

Come join us for our annual Solarfest workshops~
This years workshops include:

Overview of Timberframing with Round Timbers
Saturday at 2pm
Sunday at 10:30

Permaculture - Zone 1 - Shelter
Sunday at 1pm

Sunny Brook Open House!

VbC - Village Gathering 2012

A little snippet of this years VbC -  Village Gathering skill share weekend at Twin Pond Retreat in Brookfield, VT.   See more at www.vbc-vt.org.  It was a great success with over 50 workshops and over 200 people.  See you next year!

Masonry/clay oven plastered at the VG

Welcome booth and Pavilion

Sierra presenting on Natural Plant Dyeing

SBF # 24 Energy Star window ratings and NFRC

Did you know that most windows come with an NFRC(national fenestration rating council) sticker that gives you a list of performance values that are not for that actual window?

I found this out because Energy Star requires all windows to have a U(1/R) value of .32 or better(lower).
I have 4 Pella windows with a U value of .33.  I thought that I could improve this with a low E film applied to the inside and began a discussion with my energy mentor Andy Shapiro.  We found out that the number on the sticker is given for a standard window size with the given glass and frame.  The standard size is 2'x4' and the actual window is 29"x50".  So we found the manufacturer of the glass and the specific type and matched that to a frame material in LRBL's Window6 simulation program to give us the .33 that is shown (using the standard size).  Then I changed the window size to what we actually have(29"x50"), which is a bigger ratio of window to frame, meaning the U value will be greater because the glass is more insulative than the frame.  As we expected we ended up with a slightly better U value of .32, which gives us the grade to pass Energy Star. No film needed.
If we also added the film, we would have lowered our SHGC(solar heat gain coefficient), but more drastically improved the U value to below .3.

Just made $2500 fixing up my house!

Back in January I took the Passive House Training at Yestermorrow Design/Build School.  I carpooled to Warren with Malcolm Grey of Montpelier Construction.  I was telling him about how I was planning to redo my roof and insulate it while I was at it and he suggested I enroll in Efficiency Vermont's  Home Performance with Energy Star program with the possibility of getting some money to help pay for it.
So I couldn't refuse that.
I paid Malcom $400 to audit my home and find issues including an air leakage rate of 4500 CFM50 for a 1300 sqft home.  Thats 26 air changes at a pressurization of 50 pascal. About what you can produce by holding your lips and inflating your cheeks.  Try it.

I then stripped my roof, fixed the rotten areas and filled the holes where the fiberglass was missing from animals and poor installation.  Then I applied 4" of insulation with an airtight membrane (Proclima) that I taped together.  I applied polyiso foam on one side and mineral wood on the other to compare.  I found that I could get the mineral wood tighter because it was squishier but could tape the foam creating redundant layers of air tightness.  It was easier to cut the mineral wool as well.  The mineral wool was slightly more expensive depending on your source.  Other than that installation was very comparable.  In this process I cut off my overhangs and wrapped the edge of the roof about 12".  Strapping went on top with roofing on that.

I also put 2" of mineral wool on the ext. of one gable end that needed residing and blew 4" of cellulose to the interior of the other gable end that was framed to the inside.  I added dense pack cellulose to 36sqft of area that was exposed from an old chimney and filled the top of the first floor wall cavities at the rim joist, filling a couple half way where electrical wiring was installed and the cellulose was either removed or not added.
On top of insulating I air sealed some glaring spots including the cupola hatch,the garage bay doors, the exhaust vent for the on demand heater and two windows.  There was a lot more I can still do.
Upon retesting I got my air leakage down from 4500 CFM50 to 2600!  That is an improvement of 42%.
35% was my goal for the incentive on top of 75¢/sqft of insulation with a cap of $2500.

TOTAL Estimated %
Heating Energy Savings:75.31 %
Estimated annual savings: $704.96
Estimated annual heating MMBTU savings: 73 Estimated annual CO2 savings in lbs: -912

I usually use 2-3 chords of wood for heat and hot water and 100 gallons of kero for backup heat and hot water.
I am excited to see what next year's usage is!

Thanks Efficiency Vt and Malcom.
Saving money is an incentive to making my home for efficient.  Even for an energy geek builder like me.

SBF #23 Rope Knot Reskilling

Sometimes its just cooler to use less embodied energy.
This is an eye splice.  It is holding a dumbwaiter that is in the root cellar and gives access to stored veggies right in the kitchen for easy access.
Typically we would find wire rope and a metal fastener for this job.  Why not consider an age old solution that is handsome, biodegradeable and so much lower in embodied energy than metal.
While most people might think that in the age of ADD no one could focus enough to actually do this splice, YouTube has some great instructional videos that your 5 yr old could probably find for you.  I'll make it easy.  http://youtu.be/3cZOn-vT0xA
We are trained to look for the gadget to buy and solve all our problems.  In this instance, reskilling around rope knots is all we need to add to our toolbox.
Oh yeah, the cost of this solution - nada.

The Natural Building Companion released

Friends and natural building colleagues of Ben, Ace McArleton and Jacob Racusin of New Frameworks Natural Building have just published their book "The Natural Building Companion" through Chelsea Green Publishing.

http://www.chelseagreen.com/bookstor/item/the_natural_building_companion:paperback%20+%20dvd

Ben contributed to the effort with illustrations.  The book is 448 pages and cost about $60 for tons of info and pictures of projects around the Northeast and beyond.  Anyone interested in Natural Building should be checking out this volume.

Research Report of Strawbale Houses in VT and NY

A study of 7 strawbale homes' heat loss and airtightness in the Northeast

Primary author Jacob Racusin
with McArleton,Graham
December 12, 2011

NDB worked with New Frameworks Natural Builders, the authors of a study of the energy performance of several strawbale houses built in the past 5 years. The energy audits were performed by Building Performance Services of Waitsfield, Vt.
This study was primarily undertaken to assess the strategies for air sealing strawbales using plasters. It was also useful for understanding the overall performance of strawbale enclosures and its relation to conventional construction.  This report is important work in the development of strawbale construction for cold climates. Initial results show that strawbales can be installed to perform as well as or better than any other type of construction in terms of air tightness and creating a consistent thermal barrier.

There was also data taken on moisture content that confirmed much of what we already knew about strawbale's performance with regard to moisture.

Please contact Ben if you are interested in this report.

Solar Greenhouse Update

 

The Murphy-Daley Greenhouses are through their first winter with great results.  They are reported to have not frozen during the winter holding onto 40 degree temperatures.

Tomatoes are big on the first of May and the beds are planted.  The only issue over the winter was aphids that were apparently brought in on some plants last fall that required a cleaning out of the greenhouse to get rid of them.

Hot water tubes are installed in the growing beds awaiting a hook up to the boiler or solar hot water panels.  The water tubes for solar heat storage seem to be doing their job adding to the thermal mass to keep the greenhouse temps from dipping to low.  They do not help when the temperature rises though.  Two fans were installed in the windows to the house to keep the temperature down during sunny days.

Villagebuilding Convergence 2012

Save the Dates:
June 20th: James Howard Kunsler at the Unitarian Church in Montpelier
June 21st: Summer Celebration at All Together Now
June 22nd-24th: Village Gathering - weekend skillshare and statewide Transition Town and Occupy Initiative gatherings.

See the website for details! www.vbc-vt.org

Transition Pecha Kucha #4

May 3rd, 7-9pm at the Big Picture Theater in Waitsfield, Vt
Join Transition Town Montpelier and Yestermorrow for a rousing evening of PechaKucha. Drawing its name from the Japanese term for the sound of "chit chat", PechaKucha is a presentation format based on a simple idea: 20 images x 20 seconds each. It's a format that makes presentations concise, and keeps things moving at a rapid pace.

Ben Graham featured on Vermont Green Jobs newsreel

SBF #23 Heat Distribution - Equality for all

Here is the simple distribution system for Sunnybrook Farm.  Minuteman f11 aluminum fans in the wall.  55cfm.  I believe this is a 25Watt fan, which is more than it should be.  We are undercutting doors 3/4", and they will be open most of the time.
I have heard a someone testing directional air flow distribution using smoke, who found that blowing the air from the cool space to the warm space at ground level, works the best.  We are sucking air at the ceiling because of the ability to work the airflow with closed doors and because we don't have transoms to allow air to flow through at the ceiling.  The cold air will be pushed back out under the doorways

south den with fan above door

fan wiring

in north bed, fan above door

SBF #22 Make as few penetrations as you can- electrical on the exterior wall

Exterior wall free of wires or holes

 Making a renovation airtight is a challenge.  Using the Airtight Drywall Approach is also challenging because people are used to making lots of holes in this layer.  So re-designing the electrical distribution in the exterior wall becomes an issue.
It's great in that you can eliminate all penetration sealing by not having electrical outlets and switches in the wall.  But figuring out another system can be just a tough.
I really like the idea of floor boxes, but apparently they cost around $40/box vs. the typical $1.50 electrical box.
I decided to try putting the outlets in the baseboard and switches attached to the wall in wood boxes.  We have also designed any wiring runs and ceiling lights to run in grooves routed out in trim and faux beams.
The baseboard needed to be 2" thick and 6" tall to accomodate the thinnest two gang boxes with a little room for wires to pass around the box.  The boxes have 1/4" mud rings for a two gang setup even if we have only one receptacle because we need to cover the two gang box.  We used 1" barn board for the baseboard and had to build up the edges to get the 2" thickness.
Fastening the boxes to the 1" baseboard was challenging to get a secure attachment to allow for the pressure of installing the boxes. Using 2" stock and routing a groove for wire and cutting out for boxes would be a better design.

Cap to baseboard is not shown

3 wires into each box

After installing some of the boxes into the baseboard and then wiring, we thought it might be easier to wire the boxes where they will go without the baseboard and fitting the baseboard to the boxes.  The box holes are just big enough to allow the box with mudring through.

Another way to achieve this goal of not penetrating the exterior wall with electrical boxes is to build a utility chase on the inside of the exterior wall either making the wall 2 1/2" thicker or using that much less insulation.  One way to do this is to use chipboard as interior air barrier and frame another wall to the interior, which becomes utility chase and then finish sheetrock on the interior face of that.  I find that method to take a lot of time and resources and rather like to see the outlets in the baseboard instead of the wall.  It also makes accessing the electrical easier.

Learning how to live without money - Freedom to Farm

#21 SBF search and seal

Part 1- Resolving the melting spots
In the last post I described how I was able to see the melted spots on the roof and identify escaped heat.  How exactly the heat was escaping and why was somewhat unknown.
I assumed air was allowing the heat to get through the envelope above the top of a wall on the second floor.  We found that the wall plate penetrated the envelope creating a thermal break and the air sealing was  not great.  This was confirmed with a blower door test.  We were able to see and feel warm air coming from underneath the ceiling sheetrock.  It was warm air we were able to see because it was not very warm in the house and it was a sunny day, so the heat from the metal roof was coming in through the cracks.  This was later in the day and all the morning frost was melted from the roof.
I also felt into the cavity around the cellulose where the melted spots were seen.  So the insulation contractor offered to come back to densify the area I was concerned with.  I retaped the seems around where the new cellulose was injected, caulked the ceiling sheetrock/plastic air seal and called it good.  apparently the sheetrock did not make a good seal with the gasket that seal it to the plastic air barrier that was taped to the top plate of the existing wall.
The tape was not ideally used here either as the top plate was rough cut wood which it not really appropriate for taping to.  Unfortunately, caulk is the best method for sealing to this.

On the next frosty morning we had a light snow.  It was accumulating everywhere lightly and the house was warm.  The spots of concern were not melting!  This was a good sign.  It was also noticed that the last areas that were not air sealed around the entry doors, because they were just installed, were melting, showing the warm air's path of least resistance.

Part 2 - The first blower door test.
This test was conducted before all air sealing was done and the plumbing lines were all open so we were not able to get any numbers.  But we did find our leaks after most visual air sealing was complete. What we found:
1. a gasket on the upstair door to the cold attic has a gasket on backwards and was letting air in under the door.

2. The seal to the top plate of the 2nd story bearing walls had leaks.  Some from the Siga tape to the rough sawn top plate and some from the ceiling sheetrock to the plastic air barrier connector.  This work was not done under supervision and the siga tape was being asked to do a little too much to stick to the rough sawn wood.
3. The vaporblock seal taped connection of the 10 mill plastic air seal connector to the handhewn wood sill that sits on the granite foundation.  Poor tape for the job.  Probably needed to be adheared with some kind of caulk.
4. The site built bulkhead door was not gasketed.  Easy fix, add gasket.
5. The second floor joists penetrated the sheetrock air barrier and were taped with Siga tape.  Taping to rough sawn wood is not working.

6.  The rebated, double gasketed Linnwood doors were tight except at the bottom corners were the adjustable sill sweep met the side gaskets.  They did not overlap or join together and air was allowed to leak.
7.  There was also some expected leaking at the taped joints of the plastic air barrier in the basement.  The 3M red tape was inferior to the Siga tapes.  I tried the economical approach with just using the red tape, but will have to reseal spots with better tape.  I will be trying a more local importer of quality tapes - Pro-Clima tapes from FourSevenFive in NJ.

SBF# 20 Escaped heat

How can you tell if your insulation and air sealing is effective?

On this cold morning there was a frost on the roof. And where heat was getting through, you could see the frost melted. I caught this shot this morning after it was noticed a week earlier.

So what is going on here?

The melt spots are where the hallway wall meets the top of the sloped ceiling and the flat ceiling on the 2nd floor. On further inspection, I found that the top plate of this wall actually penetrates the plane of the slope, where on the other side there is no wall and no melted areas.
I also found some air leakage where a piece of tape failed to stick to the top plate.
So the next question is does a little bit of air leakage and a 4" thermal break on an 18" cellulose cavity result in this kind of heat escape or is there perhaps some gap in the cellulose? The installer did check this area with an IR camera, but it was done when we had a much smaller stove and not a large of a temp difference as we currently are running.

What do you think?
I will follow up as we get to the bottom of this one.

SBF# 19 Local, Natural and Reused Materials

Today we made a lot of decisions around using local, natural materials for finishes. Most of it revolved around the kitchen design, which is being coordinated with Eyrich Stauffer of Worcester, Vt.
In order to make design decisions about the materials used for the kitchen cabinets and counter tops, we wanted to coordinate with the other finishes that would be impacted by these decisions and make sure everything worked together.
This included the wood floor, wood trim on the cieling, panelling on the back side of the bar- along the coat shelf and both the closet and book shelf at either end of the kitchen.
Eyrich initially suggested butternut from Vermont Wildwoods that sells Vermont forest salvaged butternut, for the cabinets. Jan liked the look of this wood along with soapstone counters. While Vermont Soapstone used to supply the stone from Vermont quarries and plans to in the near future, currently their stone comes from Brazil. Wayne likes the idea of using a more local slate. We'll see how that turns out soon, but we did come to agreement on using local pine for the floors, and planing the barn boards from the site for the paneling and window trim. We are having a tough time identifying this 100+ year old wood and are thinking in the range of fir or hemlock.
We also decided to resaw some of the old timbers from the barn into countertop material and trim for the ceiling. The tight grain of the spruce and pine is exquisite.

We found that these woods will create a consistent aesthetic throughout the house and have a similar yellow brown hue that will have a warm and relaxed feel.

Stay tuned for the post on clay plasters in the Dining/Living Room.

SBF# 18 PHPP

I have recently completed a 9 day intensive Passive House Training with Katrin Klingenberg mostly in order to learn the Passive House Planning Package (PHPP)
I am currently using this rehab as an excercise and will post the results. Passive House Institute does have a separate track for retrofits called EnerPHit. If you are interested in this check here http://passipedia.passiv.de/passipedia_en/certification/enerphit.

SBF# 17 Closing In

Most of the air sealing is complete.
The 1st floor is being mudded and taped, the 2nd floor is done. We need to seal the basement and root cellar doors. We are anxiously waiting for our 2 Linnwood, rebated, double gasketed doors. And the 2nd floor joist penetrations need to be sealed. Then we are ready for the blower door.

We did notice some spot melting on the roof where a wall met the sloped ceiling. I found a couple of old wiring holes through the top plate and an unsealed seam. But the melting seemed unlikely with such small air leakage given the 18" of cellulose. Upon closer inspection I noticed the top plate actually broke the line of the sloped ceiling, meaning we have a little thermal break here. I'd say the top plate pushes into the ceiling about 4". I am thinking that a few leftover foam pieces could easily fit between the studs to make up for the penetration.

One sign that the envelope is getting tight is that the plastic in the basement is billowing inward as the wood stove is sucking out the air. We will not notice this once the basement insulation is installed, but we are holding off for now until we do the blower door test.