Roof Assemblies... length of roof nails

International Building Code, Chapter 15

Fasteners for asphalt shingles shall be galvanized steel, stainless steel,
aluminum or copper roofing nails, minimum 12 gage [0.105 inch (2.67 mm)]
shank with a minimum 3/8 inch (9.5 mm.) diameter head, ASTM F 1667, of a
length to penetrate through the roofing materials and a minimum of 3/4 inch (19.1
mm) into the roof sheathing. Where the roof sheathing is less than 3/4 inch (19.1
mm) thick, the fasteners shall penetrate through the sheathing. Fasteners must
comply with ASTM F 1667. Staples are not permitted for shingle application
unless specifically noted in the manufacturer's installation instructions on the
shingle package. Use 4 nails for standard installations, 6 for steep slope or high
wind areas.



Minimizing wood waste during construction

To minimize wood waste, we build using dimensions 3" under 8', 12' and 16'. At the shop, we end up with a garbage can full of 2" x 4" ends. The client will burn these in his wood stove. Otherwise, we would donate them to the Jackson County Fuel Committee. We will send our clean sawdust to the compost pile.

On site, we create a bit more wood waste. Most of it is solid wood, and burnable.

For air quality, it's best not to burn plywood. I had some challenges with the siding this time, as you can see from my waste pile.

Metal waste due to broken, stripped, and bent screws amounts to a few ounces as well. We sort waste metal for eventual recycling.


Next Blog >> Gamification

I took the time to hit the Next Blog>> link on my askdanshaw.blogspot.com, and up came this (presumably random) blog on gamification, which I care about: http://jz-idte.blogspot.com/. Joe Zellner recommends Getting Gamification Right: 22 Best Practices by Susan Jacobs...

"Substantial completion"

90% complete, closed in, and dry.


Roof closed in

It's dry (and dark) inside.


Gambrel roof nearly complete

...and it's a good thing, too, because look at those clouds.


Wood Handbook: Wood as an Engineering Material, free ebook from USDA

Wood Handbook, Wood as an Engineering Material
U.S. Department of Agriculture, Forest Service, Forest Products Laboratory: 508 p. 2010


Geometric roof truss design!

This geometric roof system seems perfect for our purposes. The roof is pre-assembled with many hinges, and can be transported to the building site folded up.

At the site, the roof system is unfolded and struts are added. Installation is quick, and the entire system is very strong.


Pressure treated skids

This is the label on our 3, 4" x 6" x 16' pressure treated skids. Washougal, Washington, still Pacific Northwest...

Metal roofs and condensation

Rows of water dripping from a metal roof above a carport. A metal roof will last a lifetime, and unlike a shingled roof, installation is quick. A shingled roof has hundreds of perforations from the nails. Unfortunately, under certain weather conditions, metal roofs create condensation, and water can drip down.

Water droplets on the ceiling of a carport.

Siding of actual plywood

19/32" siding at Home Depot is made of actual plywood. So we use that. The thinner siding is made of pressboard, which is full of glue, so I don't like to use that. Roseburg is in Oregon.

Gambrel roof end truss(es)

Two end trusses will have a bottom chord and studs to attach siding.

Double top plate

Even the top plate gets a coat -- or two -- of primer (or paint). We've treated every practical horizontal surface. Water tends to collect where two flat surfaces touch.


Gambrel roof truss prototype

Gambrel derives from the Latin word for leg. Also known as a hip roof, or in Britain a mansard roof.


Wall modules fit precisely!

We constructed this modular 12' x 16' shed off-site at our workshop in 8 modules, then transported it to the job site. Because the modules fit precisely, erecting the walls took less than half a day. Before the siding and trusses can be installed, some work still needs to be done. In the right foreground of this photo, you can see the first piece of the top plate has been installed.


Floor system complete

The next step, we will secure the sill boards.

Floor: 3/4" tongue and groove plywood, and glue

We used PL400 and similar glue designed for the purpose. The tongue and groove is designed to have a 1/8" gap to allow for expansion.

Elevation above soil

The sub-floor is elevated above the soil. Heavy duty ground cloth is followed by 3" of gravel. On the "low" side, two courses of 1" blocks. Then 4" x 6" pressure treated. Followed by 2" x 6" with two coats of Zinnser primer (or bones paint). For a total of 16" to 17" of separation between the soil and the floor. The underside of the floor is also treated.

Sub-floor: Joists

This floor is approximately 12' x 16'. The center is supported by a 4" x 6" x 16' pieces of pressure treated skids. The floor will eventually be tied to the skids with lag bolts design for pressure treated lumber.

Site selection for your shed

If you have a choice of sites for your shed, choose a site that is in a high spot and well-drained. This location is clayey.


Floor joists assembled

That's me, at the end of a day's work. The sun came out, but temps were chilly. My client did a great job of leveling the blocks for the pressure treated 4 x 6's. Pressure treated tends to warp a bit. I make sure the bow (if any) faces up. The plywood will be glued to the joists. Other surfaces will be primed before the plywood floor is installed.

Transporting the pre-fab modules to site

The pre-fab 8' x 8' modules stack nicely onto our rental truck. Having John's help was vital. Getting those modules onto the truck by myself would have been a struggle.