the anatomy of a roof

The Anatomy of a Roof

For most of us, the roof is nothing but “that thing that keeps the rain, snow, and sun out of our homes.” For others, roofs are an expression of architectural style or epoch, a statement to a time that’s past or will only become something to talk about. But, the roof over your head is so much more than you can imagine.

On that note, let’s take a closer look into the anatomy of this marvel of engineering that keeps the birds and bats, bugs and dirt, rain, wind, hail, and dust right where they need to be – outdoors.


The deck is the structural base everything is built on and usually made of wood or plywood.


Underlayment is the next layer; it is the protection between your roofing material and the deck. It is designed to provide a certain amount of insulation and be watertight.

Roofing Material

Concerning roofing material, roofs can be very different from one another. Residential homes can feature almost anything from tile, metal, shake, shingle, or stone. Commercial buildings usually feature those same materials, although there could be some additional categories like built-up roofing, foam, single-ply, modified bitumen and more.


The purpose of fasteners is to attach the roofing to the underlayment and deck; different types of material require different attachments. For instance:

  • Asphalt shingles need roofing nails
  • Tiles need a metal fastener
  • Certain types of roofing require sticky paper, sticky tar, or even glue to bond the roof together


Coating (i.e., a coating layer) is the final boost that helps the weather resistance. The coating can be applied at the very end or may be built into your roofing material already – either way; it’s good to have this kind of security for your roof as it’s providing extra insulation, protection against heat and UV rays and therefore a longer lifespan for your roof.

While coating does seem like the last element of completing your roof setup, all kinds of extras are added during the entire process.

The following are just some of them:


Flashing is installed at the joints of different planes of the roof (valleys, eaves, dormers, gables, hips, etc.,) and it helps reinforce those areas against the weather. Flashing should be of waterproof material.

Drip Edge/Gutters:

Although “additional” parts of your roof installation, gutters make for an essential element of proper roofing; they channel water off your roof and away from the foundation of your home.


Vents are yet another crucial element of “additional” roof anatomy. Vents help roofs breathe, and therefore eliminate the possibility of mold, rot and more.

With everything that you know about roof anatomy, you need to know something else, too – no matter what quality materials you use; if the installation of your roof is done poorly, you are looking at a disaster for your roof and your wallet. Make sure the roofers you hire are professionals, with an excellent experience. If you need consultation, click here for a FREE estimate from 1-800-HANSONS.