Question on Insulating PM houses

[orbit1]

Has anyone enhanced their PM house with insulation? I have a Coates Wateredge and a modified Trio Grampa, and I'm wondering if insulating the attics of these houses would be beneficial. If so, what type of insulation was used. Has anyone conducted any temperature study related to with and without insulation.

Thanks in advance.

Dave

[Guest]

Dave,

Indeed, there have been studies regarding the insulation of martin houses. There was an article about this in a recent issue of the PMCA magazine. In short: the author coated an aluminum house with a kind of polymer paint (Plasti-Dip I think the stuff was called) that was originally intended to coat tool handles; and the author also installed a nozzle that would spray a fine mist of water onto the roof of the martin house.

A "coated" house reduced the cavity temperatures slightly, by perhaps a few degrees over a standard house.

A "coated" house that was equipped with a spray mister reduced the cavity temperature by a great deal. I believe it was around a 20-degree F difference.

Very impressive results.

In regards to insulating your martin houses, I'd say that it would be a good idea, in theory.

[orbit1]

Thanks for your response. Yes, I saw the article that you speak of but it only addressed coatings and heat dissapation with water spray. This deals with emissivity, which is suface characterisitics of the radiating body. I'm wondering about actually adding insulation to the houses attics. One thing I've read is that the Alamo Lonestar house is insulated. Does anyone know what is insulated on it, and what they are using?

Thanks,

Dave

[John Miller]

Hello

I've become a proponent of insulation -- more for cool springs than hot summer.

The PMCA recommends putting a sheet of styrofoam in attics of aluminum houses. This may make it cooler below -- can't hurt and may especially help the top level. When I put 3/4 inch thick styrofoam in attics of several Trio houses, I quickly learned you have to taper the sides back to get the roof top to fit back on.

I also insulated walls of several aluminum houses by gluing on 1/8inch thick styrofoam, from a roll of six-inch wide pink styrofoam -- it's made for foundations. You just cut a piece to fit, apply a very thin layer of construction glue and press it on. I think this helps in spring cool periods, and surely makes the interior wall itself cooler when the sun is shining on it. My martins seem to like the house -- five pairs in a new site house of 9 compartments -- but its risky to say why martins choose a particular location.

There is an article in the archives ("martin house temperature tests") which found that aluminum houses are no hotter than painted gourds, but they didn't test insulated aluminum.

John Miller,
St. Louis, Mo

[orbit1]

Thanks John. I'm curious, is there a reason that fiberglass insulation hasn't been used? If it is encapsulated in plastic, wouldn't that be better?

Dave

[Guest]

If it [the insulation] is encapsulated in plastic, and you have easy access to it, and the plastic won't deteriorate or be accessible to the birds, then go for it. One reason styrofoam sheet is recommended may be because it is so common. Packing materials for appliances and such.

Help me understand: In a previous post you said "This deals with emissivity..." Which would mean the surface characteristics of the martin house roofing and walls. If memory serves, insulation is more in line with conductive heat transfer, yes? Combining radiative heat transfer with conduction, you'd want to go for highly reflective outer surfaces, with good insulation around the nesting compartments.

[Sparky]

I'm planning on coating my aluminum housing with a paint containing a powdered ceramic insulation for next season. These powders are available to mix with any type of paint. The paint can then be brushed or sprayed. Spraying is recommended for even dispersal of the particles. Should be interesting to see what temps come about.

[orbit1]

Help me understand: In a previous post you said "This deals with emissivity..." Which would mean the surface characteristics of the martin house roofing and walls. If memory serves, insulation is more in line with conductive heat transfer, yes? Combining radiative heat transfer with conduction, you'd want to go for highly reflective outer surfaces, with good insulation around the nesting compartments.

I meant that the article you mentioned delt primarly with coatings which affects emissivity. Also, you'll notice that the data didn't reflect a big difference in temperature. I believe that if the roof would have been white, the temperature would have been a little cooler, considering white reflects all colors of the spectrum. Your right that you want a highly reflective surface in order to reduce the amount of heat transfer.

BTW: Am I conversing with another engineer?

Thanks for your input,

Dave

[Guest]

Mechanical Engineering graduate student. Been working with martins (and birds, in general) since high school, so the hobby has stayed with me.

[orbit1]

Mechanical Engineering graduate student. Been working with martins (and birds, in general) since high school, so the hobby has stayed with me.

Well, then your the man with more of a grip on thermodynamics than I. I'm just an electrical engineer. Not as much emphasis on thermodynamics as you gear heads! Anyway, thanks for the feedback.

Dave

[Guest]

Hello fellow engrs. I am but a lowly civil engineer but do have an opinion on the attic insulation. I have a foil-faced cellular insulation (a single layer) in the attics of my aluminum houses. It's a bit like bubble wrap-except its much more substantial and foil faced. I attached it with what I call 'tin tape'-a heavy duty aluminum duct tape around the edges. You can find this insulation at home centers in 18" and 24" rolls, as well as the tape.

I agree with some of the other posts that it does some good in the cool spring, but its value is probably limited in the dog days of summer. However, I put this insulation on the inside of my west facing aluminum garage doors (just with a bit of construction adhesive F-26, liquid nails, etc. and actually it looks pretty good) and it made quite a big difference in the garage temperature during summer. So I think it's worth the hassle for your colony.

I'm afraid my knowledge of bending moments and modulii of elasticity are no help in this argument.

[orbit1]

[quote="J Gragg"]Hello fellow engrs. I am but a lowly civil engineer but do have an opinion on the attic insulation. I have a foil-faced cellular insulation (a single layer) in the attics of my aluminum houses. It's a bit like bubble wrap-except its much more substantial and foil faced. I attached it with what I call 'tin tape'-a heavy duty aluminum duct tape around the edges. You can find this insulation at home centers in 18" and 24" rolls, as well as the tape.

Thanks for the input. I'll look into this a little more in-depth.

Thanks again,

Dave

[John Miller]

Well guys. Today it's 97 in St. Louis, and with this discussion, I thought what better day to test the inside temp of my aluminum martin house. (All my martins have fledged)

This is a modified Trio (deep compartments), with 3/4 inch styrofoam in the attic, and 1/8 inch styrofoam glued to inside of exterior walls.

I put a basic outdoor thermometer (not digital) in a closed back compartment, top floor, with the side exterior wall facing south. It was 97 degrees outside, 2:30 p.m., mostly sunny.

After 20 minutes, I opened the back panel, took out the thermometer and to my surprise it still read 97 degrees.

This test won't meet any NASA standards, but is promising. It's supposed to reach 100 here tomorrow, if you engineers want to fly in for more tests, I'll lower the house for you.

John Miller,
St. Louis, Mo

[Guest]

Just send me some plane tickets John. I'll waive any fees as long as you take me over for a brewery tour.

[John Atteberry]

I was just wondering how you put the roof cap on the grandpa house when it is bolted on top of the trio pole? To put it on the multi-purpose pole that is with the roof cap! Did you rivot it on the house? Was just wondering, because I was going to get that pole, but was wondering how to put the roof cap on! Is the pole good and is it what you expected? How many martins did you get on that pole (multi-purpose pole)? I'm still thinking of getting it, but want to wait to see how many landlords have it and are happy with it! And to see how many martins the pole set-up can attract! Let me know! Thanks John!

[Donnie Hurdt MN]

John, I have the multi-purpose pole and I love it. I have a Pioneer and a Coats/Watersedge on it and four gourds underneath and two gourds on the sids of the houses. A strong well built pole that is easy to raise and lower. All I need now is some martins to nest on it!

[orbit1]

I was just wondering how you put the roof cap on the grandpa house when it is bolted on top of the trio pole? To put it on the multi-purpose pole that is with the roof cap! Did you rivot it on the house? Was just wondering, because I was going to get that pole, but was wondering how to put the roof cap on! Is the pole good and is it what you expected? How many martins did you get on that pole (multi-purpose pole)? I'm still thinking of getting it, but want to wait to see how many landlords have it and are happy with it! And to see how many martins the pole set-up can attract! Let me know! Thanks John!

John,

Yes, I pop riveted the top onto the house. As far as the pole goes, it is of high quality and I'm happy with it. Unfortunately, I'm still trying to get PM's in my area so I can't help you with that information.

[Guest]

And of course, another mechanical engineer feels obligated to chime in!

A quick question, are you placing the insulation just above the ceiling of the compartments on the top layer (below the attic......similar to the way insulation is placed in your family home) or are you placing the insulation above the attic, against the roof line......ie., the sloped part of the roof that sheds water?

I wonder if placing the insulation against the roof would help prevent heat transfer into the attic portion of the house and might allow some heat transfer between the top level compartments and the attic (if the attic has a lower temperature than the top level compartments). Might be a wash.....but a lower attic temp is a good thing. If nothing else, the house would probably heat more slowly in the morning and might cool faster in the evening so the average temp might be lower. Might also result in a reduced peak temp.

Then again, the added insulation may make the evening cool down take longer.

Thoughts?

[Guest]

My thinking is that if you put the insulation against the roof and the exterior top of the nest boxes, and then modify the house to allow more ventilation through the attic space, lower daytime nest chamber temperatures would result.

(Perhaps a similar setup along the side walls of the house would also help?)

And you're right about the insulation working the other way around during the cool evenings. Insulation is all about impeding conductive heat transfer (hot drinks stay hot, and cold drinks stay cold). An insulated housing complex, after reaching a somewhat steady-state daytime temperature, would probably take longer to cool off when the sun goes down than a non-insulated housing complex.