Page 1 of 1

Moisture issues with TBH

Posted: Sat May 21, 2016 4:49 am
by Dustymunky
I bought a TBH that was used one year and looked to be in fairly new condition. One big issue I have noticed is the shallow slope roof is almost useless. The roof is painted cedar and keeps out the water. Unfortunately the water wicks up from the edges of the roof. Water is a big issue where I live in Portland, Oregon. After a decent period of rain, most of the under side of the roof is drenched. Spots of mold spring up. I have resorted to throwing a piece of rubber roofing over the top of the hive when rain is expected. This keeps it dry but is kinda goofy imo. Does anyone else have moisture issues with the TBH roof? P.S. My TBH looks exactly like the one that Bee Thinking sells.

Re: Moisture issues with TBH

Posted: Sat May 21, 2016 7:13 pm
by Mycroft Jones
I had perfectly good roofs, but moisture was still a huge issue. I live a little north of you, same climate and humidity. The answer appears to be having a "moisture quilt" so the vapor emitted by the bees can escape. Ordinarily, bees don't need these, but we are in extreme territory, humidity-wise.

http://mudsongs.org/moisture-quilts-vs-hard-insulation/

Re: Moisture issues with TBH

Posted: Mon May 23, 2016 7:20 am
by trekmate
I live in one of the wetter parts of UK and have never had moisture problems in the roof of my TBHs. My roofs are deeper (minimum of four inch sides) than yours (by the photos on bee-thing) and allow a good airflow over the top-bars. For the roof covering I use aluminium sheet (litho-plates) recycled from the printing industry. These ensure the roof is water-tight.
I also keep an old pillow-case, stuffed with wood shavings, above the top-bars which insulates and will also act as a quilt.

Re: Moisture issues with TBH

Posted: Fri May 27, 2016 3:28 am
by Chuck Jachens
What about painting the under side and sealing the wood? Use paint that resists mold.

Re: Moisture issues with TBH

Posted: Thu Jun 02, 2016 11:47 am
by Dustymunky
Thx for the replies. I think a steeper slope to roof, painting underside edge of wood roof and a moisture quilt will all definitely help keep the moisture down.

Re: Moisture issues with TBH

Posted: Thu Jun 02, 2016 10:27 pm
by Imker Ingo
I have looked at fotos of the TBHs on Beethinking, some have cedar and others a different roof, but all pretty shallow and almost no overhang past the hive sides. You may need to make a whole new roof with a greater pitch, or modify the existing with a much wider roof. Let's us know how you get on.

Re: Moisture issues with TBH

Posted: Sun Oct 30, 2016 7:30 pm
by Dustymunky
I have kept rains out of hive by covering it with a piece of scrap rubber roofing material. There was a lot of moisture still condensing to the combs, ceiling and walls in the hive. Bees seal all the top bars together with propolis so I don't think a quilt on top of bars would be effective. Bees also propolised all the upper screened vents the hives came with. I ended up making a false top bar out of a 1/2" piece of cedar. Drilled a bunch of holes in it and put a piece of #8 hardware cloth over the screen. I put the vent bar at the end of the bees available area next to last comb of honey and mounded cedar shavings on top of the vent holes. Seems to be working pretty good so far.

Re: Moisture issues with TBH

Posted: Sun Oct 30, 2016 8:49 pm
by Nordak
Dustymunky wrote: I ended up making a false top bar out of a 1/2" piece of cedar. Drilled a bunch of holes in it and put a piece of #8 hardware cloth over the screen.

I made up some of these as well and have been pleased with them. The bees tend to propolize over the holes if I use them any other time than winter. I think it helps.

Re: Moisture issues with TBH

Posted: Tue Feb 21, 2017 3:42 pm
by GregV
One issue with a "traditional TB" hive is that it was never envisioned for a moist temperate climate.
It is more for hot/dry conditions - African and Mediterranean places and the like.

Think about it - do any of you living in the temperate zones have houses WITHOUT attics?
I bet not.

Well, the temperate/cold zone hive must have attic as well - this is not what the traditional TB hives assume and designed for.

The hive "attics" should be configured and work just as in any of the human houses - well insulated and well ventilated at once.
Exact implementations will differ, but the idea is the same; just think how your own attic works.
As simple as that.

Re: Moisture issues with TBH

Posted: Tue Feb 21, 2017 8:01 pm
by Nordak
That's why you'll see many folks put deep gabled roofs on their TBHs. It functions similarly. I have one on a hive myself. One thing you have to understand is the bars themselves are often not air tight and will let the hive breathe. A top entrance which is what I've started using almost exclusively also helps alleviate moisture. I live in a damp, humid environment myself certain times of the year and have yet to have any moisture issues with TBHs. The vent bar was most likely overkill on my part.

Heat. Now that is a bigger problem with the TBH from my experience, especially a more shallow design. To offset this, I am looking to add some polystyrene insulation in the future to combat stress from heat.

Think about it - do any of you living in the temperate zones have houses WITHOUT attics?
I bet not.


I used to live in a trailer. They're everywhere here. :D

Re: Moisture issues with TBH

Posted: Tue Feb 21, 2017 8:42 pm
by GregV
Nordak wrote:..I used to live in a trailer. They're everywhere here. :D


Yes, I get it that the top bars are not hermetically locked.
Bees can only propolise so much.

Well, the trailers are reasonably well insulated.
This is compatible to having polystyrene insulation on the top - a reasonable alternative to an attic.
The commercial buildings are done this way - no attic, but heavily insulated tops prevents condensation.

Re: Moisture issues with TBH

Posted: Wed Feb 22, 2017 5:31 am
by SiWolKe
Very interesting exchange.
reminds me of a problem Germany`s low energy homes now have.
There are homes, which are hermetically isolated to lower energy use to such a degree your solar panels or wood chip heat units are sufficient for you to be independent.
But now you have problems with condensation because of the isolation.
Since, to prevent those, you have to open your windows and change air every 10 minutes, which is not possible, you need a unit to change air constantly, which once again uses energy, even in summer.

They are now back to isolate only the attics and roofs.

Re: Moisture issues with TBH

Posted: Wed Feb 22, 2017 3:20 pm
by GregV
SiWolKe wrote:...They are now back to isolate only the attics and roofs.

Haha! Exactly!
The walls/windows/floors still need to be energy efficient, but NOT to the point of craziness where the home is similar to a space station.
And very importantly - there must be ways for moisture to escape (implementation is location-dependent).

And now - the beekeepers should be learning from the house-builders.
This is a missing link I am tired of finding.
Somehow the beekeepers fail to learn from the ways their own homes are built.
And yet all the answers are right in front of them. Crawl up and see what is going on in your own attic.

Several years ago I finished building my own house.
Along the way, I read through tons of literature about energy efficient building (while still being cheap).
The short answer - insulate the attic using loose material and keep it ventilated too (typically above the insulation) .
This directly applies to the beehives.

Re: Moisture issues with TBH

Posted: Wed Feb 22, 2017 5:57 pm
by SiWolKe
Beekeepers ( those who treat) tell me you need the open floors in my area ( mesh varroa floors) throughout the year.

Next, they tell me chalk brood is a problem.

I know, susceptibility to chalk brood is hereditary but can be keep more at bay if brood nests are not chilled.

No, they think bees need the ventilation to keep at bay the chalk brood and to make a brood brake. Bees, in my eyes are sensitive to outside temperature, open floor or not. But open floors make them use more energy.

Bees do their own ventilation. Trees have no open floors. They have open side gaps sometimes or openings you might compare with a top entrance or more entrances than one.

Re: Moisture issues with TBH

Posted: Wed Feb 22, 2017 6:39 pm
by GregV
SiWolKe wrote:.. Trees have no open floors..

Exactly.
Solomon P. does no mesh floors.
Michael B. does no mesh floors.
The bees must be able to control the hive environment - those mesh floors just get in a way.

Bees survived for many millions years just fine with no human intervention.
The parasites and disease came and went.
The bees stayed on buzzing.
No mesh floors.

Re: Moisture issues with TBH

Posted: Wed Feb 22, 2017 6:46 pm
by SiWolKe
GregV wrote:Bees survived for many millions years just fine with no human intervention.


Since varroa came the humans changed this. Hopefully some of us are able to rescue tf bees so the honeybee is not extinct in europe or will only survive with treatments.

Re: Moisture issues with TBH

Posted: Wed Feb 22, 2017 7:39 pm
by GregV
SiWolKe wrote:
GregV wrote:Bees survived for many millions years just fine with no human intervention.


Since varroa came the humans changed this. Hopefully some of us are able to rescue tf bees so the honeybee is not extinct in europe or will only survive with treatments.


The varroa is just another blip in the bee evolution.
The bees will continue on just fine IF they are allowed to do so.

Re: Moisture issues with TBH

Posted: Mon Mar 06, 2017 11:06 pm
by trishbkworm
There is a small book/long paper that talks about the issue of moisture and ventilation in a hive. The author's point was that the bees are better left to control it themselves. IT is written in a pretty opaque style, but I took home a few key messages about ventilation. The title "constructive" meant that the beekeeper was providing housing in a way that helped the bees achieve their goals needed for survival, such as stay warm in the cluster with minimal honey expenditure, or reduce the moisture in nectar. The author looks at bee behavior like trying to propolize a screen intended for ventilation as an indicator that the ventilation is forcing the bees to work harder than if it was not present. One of the most intriguing points made was that when the bees would be working nectar into honey at night, this would favor a lot of condensation buildup (under some conditions) on the walls. That would be great for the bees - it would trickle down the walls and be easily removed from the nectar. The bees also prefer to direct ventilation - in on one side of the hive entrance, out the other.

http://småbruk.se/publication/view/cons ... eekeeping/

if you want to read it!

Also the bees strongly prefer a smaller entrance - 2 x 2 in max - which argues that they can better ventilate by their own hand.

For the record, I have horizontal top bar hives with 3 cork-sized holes for an entrance. I do not see moisture buildup at all on the roof....

Re: Moisture issues with TBH

Posted: Tue Mar 07, 2017 12:06 am
by moebees
I have not read the article you site but agree with every one of your take away points.

Re: Moisture issues with TBH

Posted: Tue Mar 07, 2017 6:32 am
by SiWolKe
Thanks for the link, Trish.
It´s good to go back to basics now and again to improve one`s managements.

Maybe this is of interest to you:
http://www.elgon.es/diary/

It´s the story of a commercial tf beekeeper.
Observe his hive setups and his methods, which allows commercial bees to survive even being exposed to stress conditions.

Re: Moisture issues with TBH

Posted: Sat Jun 17, 2017 2:10 am
by cooperksmyr
I talked to a 3rd generation beekeeper and he said that I shouldn't even try to use screened bottom boards because they'll just fill them with propolis

Sent from my MotoG3 using Tapatalk

Re: Moisture issues with TBH

Posted: Sat Jun 17, 2017 2:40 am
by Dustymunky
My bees propolised all the upper screen holes on the top bar but they didnt propolise the bottom screen. I dont think they like all the extra ventilation tho. I would stick with solid bottom board personally.


Sent from my iPhone using Tapatalk

Re: Moisture issues with TBH

Posted: Sat Jun 17, 2017 3:05 am
by moebees
Yes, stay away from screened bottom boards.

Re: Moisture issues with TBH

Posted: Sun Jun 18, 2017 8:55 pm
by GregV
moebees wrote:Yes, stay away from screened bottom boards.


Well, one of most successful member of our local community here does exact that - screen bottom boards year around.
So.........

The more I think/research about it, the more I think top or bottom ventilation is less of an issue.
The more important negative issue to prevent is drafts.
The drafts must be blocked.
Once the hive is drafty, the bees will have to put in very significant effort to condition the micro-environment of a hive.

If the hive has bottom-based ventilation (screened slots/entire floor made of screen) but totally drafts-proof and insulated top - this is a satisfactory model and it works. I know of multiple of live examples of this model.

If the hive has top-based ventilation (top entrance(s)), this is also fine, but then must have solid drafts-proof bottoms; insulated top still should benefit. I know of multiple examples of such models as well.

I personally build my equipment with bottom-based ventilation and tight/insulated tops.