Small Building Construction, Part Nine

Dear Preppers and Survivalists,

Normally the roof of a house will be added before any doors or windows are installed.

Why?

The roof protects the inside of the building from rain and other wet/damp weather. This protection prevents the floor from getting wet and other damage. Now, a roof can be made of different material. Most houses have asphalt shingles. Other homes have metal roofs, and some homes use other material such as cedar shakes, slate tile, clay tile, thatch, and ...

We decided to install a metal roof because I have no/little experience putting up shingles. My brother Jumper says it's easy. Well, he wasn't around, so ...

There are three ways of installing a metal roof

Barn with Replacement Purlins, Rafters, and Posts Installed

First, purlins mounted to the rafters. This is the easiest and least expensive. Once the pulins are on the rafters, the metal roof can be installed on the purlins.

The picture to the left shows the repairs to our barn that burnt, a couple of months ago. The purlins are the horizontal pieces of wood on the barn's roof.

The replacement metal roofing will be added in a few hours then the metal siding.

Chicken Coop showing Rafters
and
some of the Purlins Installed

Now, as I mentioned before, I notched the rafters to accept the purlins, on the chicken coop. Since the chicken coop is so small, I only needed two purlins, at two feet and four feet.

You will also notice another difference between the two buildings. The purlins overhang on the chicken coop because I wanted a one foot overhand on all sides of the small building, and the purlins on the barn are flush with the sides of the barn.

Once the purlins are installed the metal roofing goes on. The roofing is screwed or nailed to the purlins.

The next method of installing a metal roof requires decking to be mounted to the rafters. Roof decking is commonly OSB or plywood. In the old days, 2 X 12s were used.

When installing decking, make sure to follow the manufactures directions. The OSB we used requires an 1/8 inch gap between each piece of OSB.

Needless to say, once the decking (no purlins are needed) is installed the metal roofing is put up. Normally, the roofing is screwed on.

The last method of installing a metal roof requires roofing felt to be laid over the roof decking. Now, the roofing felt is installed in a specific manner.

First, the bottom piece is rolled on. There are two ways of doing this. For a small roof, like the chicken coop. I cut the roofing felt on the ground just a little bit longer then needed, rolled the cut piece of felt, went over to the roof and applied the roofing felt.

For larger roofs, I would take the whole roll and roll in out onto the roof. Using whole rolls until the roof was completely covered with roofing felt.

Second, another piece of roofing felt is added. The second piece overlaps the first piece.

Why?

If any water gets under the actual roof, the water will continues running down the roofing felt without getting the inside of the building wet.

Of course, you can see that I went with the most complicated and expensive method of installing a metal roof. It was unintentional.

Either way you go, it's time to add the metal roofing.

Metal roofing is easy to install, once you get the first piece level and plumb.

Needless to say, it didn't happen that way for me.

More about that later.