Image Credit: Lunos Lueftungstechnik
More Musings of an Energy Nerd
A new distributor of building products from Europe has set up shop in Brooklyn, New York. The company, called Four Seven Five, was recently founded by a trio of Passivhaus consultants: Floris Keverling Buisman, Sam McAfee, and Ken Levenson. Four Seven Five plans to import air-sealing products and ventilation fans from Germany, as well as HVAC equipment from Denmark.
One way to describe Four Seven Five: it’s the Small Planet Workshop of the East coast. Like Albert Rooks of Olympia, Washington, the Brooklyn triumvirate behind Four Seven Five imports European air-sealing tapes. Rooks sells Siga tapes, while Four Seven Five sells tapes manufactured by a competitor, Pro Clima of Schwetzingen, Germany.
All kinds of tapes
Pro Clima makes window tapes, sheathing tapes, housewrap tapes, and vapor-retarder membrane tapes. Like tapes made by Siga, Pro Clima tapes have an aggressive adhesive that is free of VOCs.
Like other high-quality tapes, Pro Clima tapes come with a slick paper peel-away backing. We’re all familiar with the frustrations of such tapes: for one thing, few carpenters have fingernails that are sharp enough to get the corner of the peel-away paper started. And when the paper backing is finally off, the tape tends to curl into itself, causing the dreaded “sticky side to sticky side” disaster. Okay — that length of 80¢-a-foot tape is ruined. I guess it’s time to cut another length of tape and try again to peel away the corner of the paper backing. I wish I had a teenager with sharp fingernails to help get this corner started …
Of course, once you have successfully navigated the peel-and-stick-and-stick dance, the tape works great.
Most Pro Clima tapes come in a single width (3 3/8 inch). Each roll of tape is between 65 feet and 98 feet long and sells…
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45 Comments
Outcomes?
I can hear all the concerns about applied performance and longevity that have been voiced on GBA and in your blogs, so I need to ask:
any thoughts,Martin, on the effectiveness or longterm performance of the tapes and wraps? I imagine they haven't been in use for decades -- do we expect them to be more reliable than (cheaper) tapes, sealants, wraps more commonly used?
Lunos fan recovery effectiveness
Martin,
How effective is the heat recovery of the Lunos fan?
One thing to consider with those fans when comparing them to a ducted HRV would be the space required for all the ductwork.
A house with mini splits and the lunos fans would free up a designer from having to keep in mind where the duct work will go. The question is how does the recovery compare with a centralized HRV?
Andrew
Response to JoeW: Outcomes
JoeW,
The longevity question is one that we all struggle with. You were asking Martin, but I did want to a least share what we know.
Both companies (Pro Clima & Siga) are key suppliers in the Central European markets. Air-sealing by tape and membrane is about 25 years old in CE. So really, all that we can look at is 25 years of history. When you ask the "how long" question to the manufacturer, all they can says is that: "We've been making them for this long, have been on hand during remodels and seen old work, and the tape has stayed stuck". In addition to that they run rapid aging tests that quickly alternate hot and cold with other effects like mass UV in the best possible effort to replicate what happens over decades. I think that they do their best, but in the end, we don't have a way of knowing the future. All we really have is limited anecdotal evidence over the last 20+ years.
Here is one: German born Project Supervisor at Green Hammer in portland OR http://www.greenhammer.com, sent me a picture of one of the Siga tapes that he used to repair the cowling on his pod air compressor. He stuck it on in Germany about 10 years ago. The Tape was Siga Sicrall. I just saw the same compressor on one of his job sites about a month ago still intact and in perfect shape. I think any other tape would have just been a dirty spot on the cowling by now: Just a little dried up adhesive blacked by dirt where the tape used to be. While I'm not conversant on Pro Clima, I'd certainly put their materials in the same class.
I know that as "Dealers" we are tainted with the brush of commercial self interest. However, i do want to note that both myself & the rest of the gang of The Small Planet Workshop, as well and the "475 Tiumverate" (Ken, Sam & Floris) have all come up from the ranks of the Passive House Movement (yes, we actually call it a "movement" these days...).
Myself and the SPW gang all met through our work in support of Passive House Northwest http://www.phnw.org, and the 475 gang from Passive House NewYork http://www.nypassivehouse.org. Regardless of weather you think that adopting The Passive House Standard is extreme or not, this is a great case in point that "raising the bar" brings significant change.
What got our two companies into importing these things was the tremendous steps that had to be taken to reach Passive House levels of design and construction. It quickly becomes apparent that there is a world of other methods and idea's that could help anyone build any envelope -to a higher performance level. Wether it's a Passive House project or not!
Not to be too self referential, but what is driving us in this direction is not the commercial self interest, but the "gee wiz cool" of finding things and methods that we think are efficient and valuable to the US. No one get's into these high performance products in the middle of such bad economic times, and intending to supply such an inexistent market without having a complete commitment to really stepping up the building envelope quality. I think that I can speak for both groups that the sincere goal is to help move US envelope quality up.
Lunos e2 Fans
Martin,
Could the Lunos fans be used to exhaust moist environments such as bathrooms? In frigid locations such as the Northern US and Canada, would the alternating airflow eliminate the possibility of the moisture condensing and freezing?
today's blog
great blog!
Martin, Here is a trick for you...
Stated problem: "Like other high-quality tapes, Pro Clima tapes come with a slick paper peel-away backing. We're all familiar with the frustrations of such tapes: for one thing, few carpenters have fingernails that are sharp enough to get the corner of the peel-away paper started."
Ok... so there is a solution to this that does not require a teenager...
Don't try to peel the backing paper away from you. Instead, hold the tape in your hand with the finished side to you and the backing paper away from you. On really good tapes like Pro Clima there is A LOT of adhesive. Enough so that if you run your thumb over the top of the tape (perpendicular to it) you'll catch some stray adhesive and it will peel the tape back following your motion away from the backing paper. The idea is to not try to peel the backing paper away, but peel the tape away backwards from the backing paper. It's one motion and can be done with one hand by just using the top your thumb.
It works on good tapes that have really thick adhesive layers. If you have any samples of Pro Clima, 3M 8067, or any of the Siga Tapes around try it and let us know if "you have the talent"!
Response to Joe W
Joe,
Q. "Any thoughts, Martin, on the effectiveness or longterm performance of the tapes and wraps?"
A. Good question. Ultimately, we don't know. Siga and Pro Clima have performed durability testing; this requires cycling the tapes through successive episodes of heat and cold to see how they hold up. However, if you want a tape to last 50 years, the only way to know for sure how well it performs is to wait 50 years.
Response to Andrew Henry
Andrew,
Q. "How effective is the heat recovery of the Lunos fan?"
A. According to the specifications provided by Lunos, the heat recovery efficiency of these units ranges from 85% to 90%.
Response to Jim Merrithew
Jim,
Q. "Could the Lunos fans be used to exhaust moist environments such as bathrooms?"
A. Yes, but you only get 17.6 cfm for $1,200. If you wanted 50 cfm (the airflow of a typical bath exhaust fan), you'd have to spend $3,600.
My advice: buy a Panasonic.
exciting products - some clarifications
We are very happy to have this forum discussing these products. To hopefully help clarify some items, I offer a few brief comments.
Longevity: Pro Clima has time tested the tapes out beyond 60 years.
Lunos/no freezing: With the ceramic core placed/pushed toward the outside grille any issues of moisture freezing is avoided. No freezing.
Lunos/cost effective: Regarding general home ventilation; if we look at the total installed cost of the system, without ducts, grilles and other associated headaches, we think the Lunos e2 will be a less expensive option. Regarding bathrooms, probably not, as Martin notes. The Panasonic (on a timer) is similar to how the Germans have been utilizing the system. You can see a typical unit layout in the e2 brochure here: http://www.foursevenfive.com/images-ezpages/475%20Lunos%20brochure%20e2.pdf
Tape technique: To follow on Albert's wise words - I'll just add that that it is true that it takes a bit of training (a very little bit) to get the hang of it. We've worked on site with a number of construction crews in the NYC area - diverse crews at that - and have found no issues with installation capabilities, nor waste. (Note to self: get tape technique instruction video up on website asap.)
Tape cost: While these are "state of the art" premium products the prices are not. The typical "workhorse" tapes range from 36 to 43 cents per LF - comparable to 3M 8067, if not less expensive. At other applications, interior OSB or membranes, tape of only 28 or even 16 cents per LF is possible. For a tape matrix overview see here: http://www.foursevenfive.com/index.php?main_page=index&cPath=70
Compact P, Magic Box: It can't be emphasized enough - that these units are for Passive House level performance homes of modest size. Given that, we'd like to note that the basic unit can also provide space cooling too.
Like Albert out west, we at 475 enjoy working closely with the building community, and are excited to offer new options for improving building performance.
tape technique
You're only supposed to peel away a small portion just to get the tape started, line it up, and then peel the back away as your are running the tape down the seam. dedicate the tape to the seam in small increments. You should have no problem with the tape sticking to itself.
@ Albert, Martin, and Ken
Thank you each for addressing the issue of tape longevity. I appreciate the conciseness and clarity! And I'm assuming no one has an example of tape failure -- either due to product or poor installation. Impressive stuff. Personally I don't mind paying more when value has been added.
More tape technique
If the tape has a split backing, it can be folded in half lengthwise over the finish side.
Once the tape is folded, the backing can be easily peeled back from the centre seam.
I find it easier to only peel back one half of the backing at a time, applying the tape in short sections as you go. Once the first half of the tape is adhered, peel back the other half of the backing and proceed as before.
Lunos e2 freezing...
Ken,
You said:
Do you know if this unit has been tested for freeze-up? If so under what conditions?
The passages through the core appear to be quite small...
I wonder if at very low outdoor temperatures, whether the ceramic core could be cooled enough during the supply cycle that interior humidity would freeze against it when the fan switches to the exhaust cycle.
Also, does the e2 have a "big brother"?
Intello and Pro Clima
I used the Intello membrane and the Pro Clima tapes all the time before I moved across the pond to Canada in 2007. I found them to be excellent products, and the split tapes were particularly good to seal the Intello to the window and door frames.
Failures? What Failures??
JoeW,
Speaking in general terms of tape as an air sealing method and not being brand specific... The only issues that we've had, and that I've heard of for good quality tape in general, is on American OSB. We supplied a project in Minnesota that was sided with the rough side of OSB and there were real issues on getting it to stay stuck. The rough side of US OSB is really fibrous. It's like trying to stick tape to sawdust. Sure it will stick, but it won't stay on the pile.
In the end, adding a primer created enough adhesion, that in the owners words:
"The tape now sticks so tight that about five minutes after installation, it’s literally unremovable."
You can read the whole thread including a comparison to 3M 8067 under the same circumstances at: http://www.minnephithouse.com/?p=905
High quality tape is great for air sealing. Much better than foam or caulking because it will handle building movements.
Cheap tape for air sealing? Well...
response to Lucas regarding possible freezeup
Lucas,
Lunos has definitely tested the units in freezing conditions - and the unit remains in balance. (They also have hundreds, if not thousands of these units already installed across northern Germany, as we understand it, without incidence of such problems.) I will try to get some technical reports about this in the coming days and repost - with a fuller explanation. But in the meantime attached here is a diagram of the e2's efficiency curve showing that even at -15 C or 5 F exterior temp, the unit is maintaining an 85% heat recovery efficiency - so the system is robust. I'll follow-up.
Tricks for removing peel-and-stick backing paper
Albert,
You wrote, "Don't try to peel the backing paper away from you. Instead, hold the tape in your hand with the finished side to you and the backing paper away from you. On really good tapes like Pro Clima there is A LOT of adhesive. Enough so that if you run your thumb over the top of the tape (perpendicular to it) you'll catch some stray adhesive and it will peel the tape back following your motion away from the backing paper."
OK, Albert. I may have fat fingers, dulled by years of job-site abuse, including hitting my digits with a framing hammer and cold-weather injuries, and several visits to the ER for stitches on my fingers. Nevertheless I still have all ten fingers and I can tie my shoes.
I've got a length of Pro Clima Tescon No. 1 tape in my hand. The backing paper isn't split, unfortunately, so there is no easy way to get it started. Your trick doesn't work for me. The paper backing doesn't separate. Your trick doesn't work for my girlfriend Karyn either. I wish it did. Rubbing the tape back and forth in hopes of making a wrinkle at the end doesn't work either. So I'm back to the method of trying to get the corner started. It doesn't want to start.
Prosthetic fingernails
Martin,
Try using a utility knife to start the corner.
Utility knife blade
Lucas,
Of all of the suggested methods (so far), your suggestion works best.
Knife
That's how I do it too - it's been many years since my fingernails extended past my fingers. Clipping a little of the corner off can help too.
The Lunos seems like a great idea. Is there any filtration?
I start backed materials
I start backed materials accidentally easily when I rip at a piece instead of cutting. By ripping usually one layer ends up a different length exposing the other layer which makes grabbing both possible to start the separation.
Martin: Your fat fingers got nothing to do with it!
You know I just can't leave well enough alone. So here is THE INSTRUCTIONAL VIDEO on how to get your tape started. In all seriousness a fairly important thing if you standing on top of a ladder. On a good day, I can do it entirely with one hand. I'd rather not be messing around with a blade.
https://youtu.be/Is28a8vJclg
Have Karyn watch the video. She can master it quickly and then provide further instruction for you...
Btw... In all fairness, this thread started with 475 and Pro Clima. I just grabbed my sample of Pro Clima Uni Tape and was able to do it the same way and with one hand. It took a couple of try's because i'm not used to handling Uni Tape yet, but that's just a short learning curve.
Hmmm... I must examine my life choices sometime... All the "smart people" in the room are working on big interesting things and I'm making videos on how to peel backing paper away... Hmmm...
Albert's video
Albert,
Thanks to the Instructions for Fat-Fingered Carpenters. It still didn't work for me until I took the tape indoors to the kitchen, put it on a wooden cutting board, and cut the edge off clean and square with a new utility knife blade. Then it worked.
I'm skeptical as to whether the method will work with job-site cuts outdoors with dull blades or snips. Possibly it will, if I practice. But there is an alternative theory from AJ Builder -- that rough cuts make for an easier peel than careful clean cuts. I'm headed back to the lab to gather more data.
AJ got it right.
Martin,
Since the trick is to catch some "stray adhesive" rather than a layer of tape, AJ's "Accidental Theory" is right one the mark. The worse the cut, the better the more exposed adhesive.
For the video, I used the Siga dispenser. It makes a not so clean cut since it has a serrated blade. Once you get "nimble" it's pretty easy.
For the Pro Clima Uni Tape, I had no problem with a clean cut by a reasonably new blade.
It only works because the "good tapes" are pretty flexible and have such a thick adhesive layer, that adhesive is literally a layer as thick as the tape backing paper and will just get stuck on your thumb. If you pull back and curl it right, the tape will just follow you.
A cheap tape doesn't have enough adhesive for this to work. I've never tried it on flashings and am now curious...
Good luck in the lab!
About the Lunos
Ken
Just wondering if it would make sense for the Lunos to vary its cycle times based on indoor/outdoor delta T...I am thinking that a shorter cycle should work better as the delta T increases?? This would require some sort of controller though...
Response to Garth Sproule
Garth,
When I was talking to Ken Levenson about the Lunos fan, I had the same idea you did. But Ken said that the developers of the fan did not include that feature. The fan apparently does not monitor outdoor temperature or vary its cycle time.
Lunos cycles
Garth,
Yes, Martin relates this correctly. I will add that we discussed this specifically as well with Lunos and their reasoning is that the balance of simplicity, cost and effectiveness are best served without the added controls. At 85% efficiency at 5 degrees F exterior temperature and only getting more efficient at warmer temperatures - there is not a compelling reason to complicate it further. It should be noted that a great deal of sophistication is embedded in the fan technology - not only reversible and extremely quiet - the fan automatically adjusts to pressure variations to maintain even cfm.
don't cut completely
cut 90% of the way across tape with a knife then hand tear the last bit. will leave a nice little handle of exposed adhesive to easily peel with.
Cut at an angle
I installed a dozen rolls of exterior SIGA tape this fall, mostly from the top of a ladder balanced precariously over an excavated foundation, and found that sticking the tape to your hand is the best way to get it off of the backing. If you're wielding a knife, try to bevel the cuts in towards the backing. As Albert noted, there's a *lot* of adhesive, and a beveled cut will reveal enough of it to get a hold of your thumb. Note that these tapes have an adhesive that sticks better to human skin than anything else (go figure), so be prepared to have to disentangle yourself at times.
It seems that tapes are like cats...
- There is more than one way to "peel" them.
I own a Lunos
I am in a "test" phase for the Lunos E2 and have been very pleased so far. I have done some temperature monitoring to see what the incoming air temps are on the supply side and have been very pleased. I tested it with an outgoing air temp of 64, an outdoor temp of 20f and at the end of the 70 second cycle (when the temp would be the lowest) the incoming air temp was 54. This may seem low, but it was only for a very short period of time. I will also note that my prototype installation only took me an hour. There is a transformer and switch that are installed in one location and low voltage wiring from there to each of the fans. The fans are extremely quiet when they are moving air, however there is a slight sound when they change directions.
I have monitored the potential for frost on the exterior side and have not seen any evidence yet. The lowest temperature we have experienced so far this fall is 10 f. My opinion is that this product is a very promising option for the future of heat recovery ventilation. The simplicity of the system is a major plus for our customers and for homeowners in the future.
Russ Hellem
Energetechs
Proclima Tapes
Folks,
I love the tape peeling discussions.
If people are really concerned about having to peel off the backer paper, Pro Clima has a Rapid Cell with has no backer paper.
We are using different tapes from both Small Plant Workshop and 475 for different purposes. Will upload some pictures later. Both companies have excellent products and run by even more awesome people.
Questions for Russ Hellem
The brochure states that there is a "G3" or "pollen filter" located at the inside opening, with only an insect screen at the outside opening. Do you see a possibility of dust, pollen or other airborn materials clogging up the ceramic core over time? Is it easy to access and remove for cleaning if needed?
Reply to Nathan about Lunos Filters
Nathan,
The foam washable filter is pretty skimpy and yes there is the possibility that the ceramic core could clog up over time, however my judgement is that it is unlikely to clog because the airflow direction is reversing every 70 seconds from pulling in to pushing out. In the event that is does clog up, the whole fan assembly and core can be slid out of the sleeve pretty easily and could be cleaned.
Through-the-wall HRVs
I just got an e-mail from Robert Bean, reminding me that through-the-wall ventilation fans with heat recovery are not new. Bean included a copy of an old brochure for the Fan-X-Changer HRV. The Fan-X-Changer was based on Germany patents. It was distributed in North America in the 1980s by P.M. Wright Ltd. of Montreal, Quebec.
Bean wrote, "It hit the North American shores back in the early 80’s. It was part of a product line patented by Kirchmeier of Germany. Likely the 1978 patent filing puts it as one of the earliest residential/retail HRV/ERV to be marketed in North America. The product line wasn’t perfect since the foam heat exchanger had less than ideal cross contamination - but from a freeze up perspective was great since it never went into defrost…picture a frosted rotating donut … The fan was the best thing - it was made by Kanaflakt which back then were bulletproof."
Unlike the Lunos fan, the Fan-X-Changer was not reversible; rather, it behaved like a Panasonic Whisper Comfort ERV. In other words, it delivered fresh air and exhausted stale air at the same location, using a single unit.
Below are two illustrations. The top illustration is from the Fan-X-Changer brochure; the bottom illustration is from the Johannes Kirchmeier's patent application.
Thanks, Robert, for your reminder about the history of HRV technology. It's another reminder that many of the energy-efficiency measures that experts are trying to get implemented today were first deployed in the 1980s.
Magic Box
Ken- Are the Nilan Compact P units UL listed now? I so want a magic box!
homebrew
unless the piece of ceramic inside the lunos is ultra expensive, it seems an inexpensive hack of a panasonic fan would provide similar results for 1/4 the price.
a ceramic core carved to fit the vent pipe, and a simple timer that reversed polarity
sure the lunos provides more wizardry, but i'd debate whether its nearly $1000 more worth of wizardry
Ceramic Heat Recovery
If the only "problem" with Lunos type HRV is the price, then the solution could be simple. Search the net for "ceramic heat recovery". They are used for the same reason in industry (in much higher temperatures). They are very cheap.
http://www.alibaba.com/trade/search?fsb=y&IndexArea=product_en&CatId=&SearchText=honeycomb+ceramic+heat+
I think any skilled builder can integrate a "smart fan", some of this ceramics and very simple controls to achieve the Lunos levels of ventilation and heat recovery.
Worst case scenario is to use non-reversible fan pairs. Only one of them are exhausting; the other is off. After tens of seconds they switch.
Response to Horatiu Vornica
Horatiu,
I think that optimizing this device presents an engineering challenge. To work well, the ceramic core must be properly sized -- not too big and not too small. The airflow rate of the fan must be optimized. The controls must include an interlock system so that when one fan is energized, the other fan in the pair is reversed. The prototype would have to be tested to be sure it didn't ice up in cold weather conditions.
All of those factors require a lot of tinkering. Perfecting the device would require building and testing at least 6 or 8 prototypes -- and testing the prototypes would require a fairly sophisticated lab.
Response to Horatiu Vornica
Horatiu,
If you think that you can meet the challenge of building your own Lunos-like ventilation system, that's great. Once the system is installed and perfected, let us know. We'd be happy to publish a blog about how you managed the feat.
Built in Lunos
I did not think to an "almost identical" Lunos HRV. I was rather thinking to a built in solution. The heat recovery ceramics could be integrated in the walls or placed in the attic. There should be no problem if the ceramic is too big. This could lead to a slower rate of switching between the pair ventilators. The ventilators could be an already proof product (e.g. like Panasonic).
May be is hard to achieve Lunos recovery performance without a lot of lab testing, as you say, but it will be closer to Lunos than to only exhaust ventilator.
Another advantage of this solution could be the summer cooling. In the summer nights when the outside temperature is lower than inside temperature this system could work without reversing the ventilators.
Lunos unit and alternatives
The Lunos unit raises a lot of questions.
If using paired units has an efficiency of over 85%, would using one lunos unit (or similar) give you 42.5% heat recovery? If so and the units were cheap there would seem to be no reason to ever use a single fan to ventilate a small house without heat recovery. If you had one unit then when it was in blow mode, some of the air would go out through materials (e.g. non-airtight insulation). Would you recover some heat from them when it went into extract mode? I'm sure you would to some extent, but would it be a useful amount?
Why use ceramics? They are used in industry for high temperatures, but for building heat recovery the temperatures are low.
The cfm is lower than for a similar sized extractor fan. Is the flow rate limited by the capacity of the heat exchanger to absorb and give out heat, or is it limited by of the obstruction of the air flow it causes?
What is the point heat loss coefficient (chi-value in W/K) through the hole/tube in the wall?
Lunos in a cold climate
I live in northern Canada and currently working for a builder trying out the Lunos. Apparently there has been success with them further north from me, I'm about as far north as Fairbanks. I'll keep you posted on its performance. I am currently working on my own house as well and looking forward to the results.
Martin, you mentioned a Panasonic for bathroom ventilation, which unit were you referring to?
Response to Greg Dumka
Greg,
Panasonic makes several models of bathroom exhaust fans. Some include lights or other features, and some are simpler, but they are all sturdy, quiet, efficient fans. Here is a link to the web page that describes the different models: Panasonic ventilation fans.
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