View Full Version : Status check - 28 July 01

Ed Harrow
07-28-2001, 08:35 PM

I found out that I still have one more friend, LOL, so got the mast moved a wee bit and got the knee wall started where ya'll can see it...

07-29-2001, 05:36 AM

I've forgotten my bow roofed shed engineering dynamics. I don't remember a knee-wall in Stimson's plans. What is gonna act as collar tie?


07-29-2001, 11:11 AM
I see you have a guard on duty.Does he/she sail with you?

Ed Harrow
07-29-2001, 06:24 PM
Jack, yes, I do seem to be a bit into uncharted territory. I actually called him to ask him about kneewalls, but he never returned my call... I did additional research in our sponsor's magazine, and found reference to setting them up on knee walls, tho no real plans were shown. The peak will be high enough above the boat that I can tie them together with a tie below the ridge. Additionally I may resort the that Medival invention, the flying butress. (Maybe not Medival, but certainly close to those days when knights were bold.)

Dasboat, that's Finbar, named after a charecter in a book, who was both Irish and a sailor. Finbar (the dog) usually stays in a boat, tho as a pup he twice fell out of a canoe. In any case that's better than his predecessor, who'd rather be IN the water than ON it. Beau caused several near catastrophies when he bailed out of smaller boats (Beau weighed about 130)

07-29-2001, 07:35 PM
Ed, If you can put up with an acrophobic barn builder then give me a shout when your ready to raise that boat shelter. I have most of the projects on the "honey-do" list complete and need a day away from NH.

All I require is a few Dunkin Donuts and iced coffee.


07-31-2001, 11:50 AM

The horizontal stability of the knee walls seems where the issue is headed. Unless you can put a collar tie at least 1/3 way from the top of the arch I don't think it's gonna do it. The design really depends on the anchoring of the bottom end of the 'thingies'. Hmm. Flying buttresses (he he). Whatcha got in mind?

G. Schollmeier
07-31-2001, 12:35 PM
Mini flying buttresses would be an elegant touch. 3 or 4 support angles per side on the knee wall side should do the trick. Once the snow builds up they get rock solid.

Ed Harrow
07-31-2001, 12:39 PM
Best I can do, easy, is this


Like I said, a little into the unknown here, but I'm hoping that the ties across the arches and across the walls and/or braces to ground will do the trick... (Also, I've driven ree-bar down thru the "sill") It can't be perceived as a "permanent structure" or the Building Inspector will not like it.

Abe, I'll be working on this (probably) Fri, Sat, and Sunday. If you're serious let me know, I'll find a DD someplace local for your needs, LOL.

07-31-2001, 01:12 PM

As I said (sorta), keeping the spread at bay at the joint between the knee wall and the base of the arch is the issue. I really think, without seeing it in person, that collar ties placed too high up are going to be pretty much useless. And, while anchoring the base of the knee wall is a good idea it isn't gonna address this issue.

How 'bout, as a simple cheap solution: Bury some two by four posts (maybe three or four per per side) at an angle. If the soil is sandy, put a large cinder block at the base. Don't need a deep hole, just enough to place the posts at a good angle. Angle the post fairly steeply and so it intersects the wall just below the joint with the arch.

Maybe I'm over-engineering here, and I may not understand the inherent resistance of that arch design to outward flexing, but even though the shed is for only a few years it seems that a heavy wet snow is going to be a problem unless you prevent those knee walls from spreading. Especially toward their centers where the end walls aren't going to hold it.

In other words, I could be all wrong, but have a close look at it.



Ed Harrow
07-31-2001, 01:29 PM
Ergo, "flying butress"! Great minds do think alike, don't we. Now let's just keep our fingers crossed xxxxxx.

07-31-2001, 02:17 PM
Sorry. A little slow sometimes. It should work fine Ed.

07-31-2001, 03:26 PM
Ed, just got back from WB school. Checked out their shelter. The scantlings were the same as yours. They had the knee wall also. I didn't pay close attention to how it was attached to the arches though. I seem to recall the outside of the arches continuing down, but I'm uncertain. The back was a 2x4 and plywood wall with a door. The front was open.

07-31-2001, 03:43 PM
The shelter that covers the Belford Gray at WB is indeed similar. But the arches do drop down to ground level. The plywood on the sides does not function as a knee wall, but does protect the lower part of structure from snow/ice damage. The arches are braced with a couple of horizontal and diagonal straps on each side.

[This message has been edited by abe (edited 07-31-2001).]

J. Dillon
07-31-2001, 04:56 PM
Has any body figured for a load of wet snow ?


G. Schollmeier
07-31-2001, 07:12 PM
I have one of these shelters. My back yard is not a friendly place in winter. It had snow 5ft high on both sides. It still looks great.