Exploring Basic Roof System Components

Roof System

Let’s go over the parts that will make up your new roof system. First we will cover the visible components of your new roof system so you will be able to carry on a conversation and be familiar with what part of the roof you are discussing.

roof system, hip roof, hip ridge, roof ridge, rake edge, roof eave edge, roof valley, gable end, roof gable
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Hip Roof System

A hip roof surface is a sloping roof surface often described by its slope in a ratio of inches of rise for every 12 inches of run. So a 6 on 12 roof hip will have a vertical climb of 6 in. for every 12 in. of horizontal run.  A hip roof system might also contain a hip valley combination as noted by the valley in our model. A valley is the point where two hip surfaces merge.

Your hip roof system will most likely include more than one hip corner set. A hip corner set is the plane where two hip surfaces merge to create a hip ridge.  Your hipped area of your roof system will only have roof eave edges and cannot contain a raked roof edge.

Gable Roof System

A gabled roof system is based on a gable end wall plane. A gable plane is a vertical section of wall which joins a sloping roof edge that once again follows the roof slope. The gable roof is called out by the rake of the roof edge. We will cover the actual framing techniques for a gable end and its overhang in another area.

Roof System Ventilation

It is most common create a ventilation system that make best use of natural ventilation. Since heat naturally rises it is preferred to create a combination intake and exhaust system for your roofs ventilation system. The best overall roof ventilation system will naturally bring incoming cooler are at all eave locations and naturally exhaust the warm climbing air at the highest point or the roof ridge. It is important to note here that you do not want any ventilation on the gable rake areas of your soffit. The reason for this is that they are located to close to your roof ridge. The rake vents would become the closest path for natural air flow and you would get no air flow from the lowest eave locations.

Roof System Eave Protection

Codes everywhere now require you to install a protective self-adhering moisture barrier along all eave edges for at least the first 3 ft. up the hip beyond the exterior wall. This barrier is in place to keep driven rain, snow, or ice from working up under the shingles and rotting the wood roof structure below. Depending on your location you may also be required to install this same product in all valley areas as well as up rake edges. There are different products available and we encourage you to invest in the rubber membrane products rather than the reinforced felt products. Rubber membrane is proven to be self-sealing around the roofing nails used to install your roofing.

You will find that we are going to cover many other sub topics that relate to the roof system in other areas of this program. This information should have given you a good overview of the basic components in your new roof system.