Building a Woods Coop for DLM in the Shenandoah Valley

[aart]

I also discovered I will need to put blocking in to support the polycarbonate roofing panels. They are too flimsy to support a snow load without it.

Usually purlins/battens are installed across rafters to support corrugated roofing, plastic or metal.

 

[Alaskan]

Is it too late to make that roof steeper? So the snow sheds?

 

[DoozyWombat]

Usually purlins/battens are installed across rafters to support corrugated roofing, plastic or metal.
View attachment 1940478

Wow, that is useful information. THANK you! I've put two rows of 2x4 blocking in already, at 24" OC, but the roofing material is flimsy enough that I'm going to put another 3 rows in, making it 12" OC. Purlins would be easier, but the two rows of blocking are already there.

 

[DoozyWombat]

Is it too late to make that roof steeper? So the snow sheds?

It is a little bit steeper than the picture shows, as the upper window was not square. I'd missed a measurement, and one side was an inch lower than the other. I pulled the nails and blocked it up, so it's square and level. Thought I was measuring everything twice.

I could make it steeper by reducing the size of the front window, or by reducing the size of the upper window. If I lived in a heavy snow area, I would cut down the front wall and reduce the front window, but I think I'm going to stay with where it is now. The blocking is going to be at 12" spacing, so that should support a 3' snow load--and we haven't had a 3' snowfall here since 1772. Cutting down on all the front wall framing would cause enough of a delay that I'd be worried about exposure to weather. I can only work on this for an hour a day or so.

The upper roof is much steeper, and should shed snow better. After seeing aart's comment, I'm going to put purlins on the upper roof--2x2s across, at 12" spacing.

Thanks for the comments. I'm obviously new to this, and they really help.

 

[aart]

Wow, that is useful information. THANK you! I've put two rows of 2x4 blocking in already, at 24" OC, but the roofing material is flimsy enough that I'm going to put another 3 rows in, making it 12" OC. Purlins would be easier, but the two rows of blocking are already there.

The blocking will help stiffen the rafter plane, but the purlins are best for nailing the corrugated roofing on.

 

[Ted Brown]

@DoozyWombat If you do purloins on the upper section I suggest that you also put in short 2" by 2"s along the top of the walls between each purloin WHILE you are at it and before the roof panels go on. This will close up those sections that will otherwise be open and a pain to close after.

Do not be tempted to screen those sections as it will interfere with the "air cushion" envelope that is a basis of the Woods design.

 

[DoozyWombat]

The blocking will help stiffen the rafter plane, but the purlins are best for nailing the corrugated roofing on.

Okay, you've sold me. Thanks.

 

[DoozyWombat]

@DoozyWombat If you do purloins on the upper section I suggest that you also put in short 2" by 2"s along the top of the walls between each purloin WHILE you are at in and before the roof panels go on. This will close up those sections that will otherwise be open and a pain to close after.

Do not be tempted to screen those sections as it will interfere with the "air cushion" envelope that is a basis of the Woods design.

Yet another thing I had not thought of. I'm generally following the sketchup drawing posted on here (somewhere,) and I hope to post a modified sketchup, showing these things that I'm learning about as I go.

And yes, I'll do the same thing with the purlins I'm now going to be putting in on the lower roof, as well.

Thanks again!

 

[Ted Brown]

One more thing to consider:

I believe your poly carbonate panels will be corrugated? How deep are the corrugations and how do you plan to close them up on top and bottom?

Remember that there are a number of predators that can get through a 1" space and most of those that can are good climbers.

 

[DoozyWombat]

One more thing to consider:

I believe your poly carbonate panels will be corrugated? How deep are the corrugations and how do you plan to close them up on top and bottom?

Remember that there are a number of predators that can get through a 1" space and most of those that can are good climbers.

They are corrugated. I don't have them in front of me, but I'd say the corrugations are about 1/2" deep, and 1" wide. A small snake could probably get in there, or a mouse, but I don't think even a young rat could make it, let alone an opossum or anything larger. I suspect that anything making it through that gap would end up being a meal for the chickens.

The ends of the purlins, however, will create 1 1/2" gaps, so the suggestion to put blocking on the side rafters makes perfect sense.

OTOH, the polycarbonate, while supposedly very good at resisting UV, feels pretty flimsy. I may have trouble with something the size of a large raccoon just ripping it off. Best I can do right now is tack it down as best I can (with multiple 1" staples,) and see how it goes.

I am hoping the electric fence I am surrounding the area with will keep out all but truly aerial predators. Multi-wire, with the bottom wire at 5" from the ground. Raccoons are both smart and aggressive, but I am hoping they will be kept away from the coop altogether by the fence.