Quick – when you think of an onion, what’s the first thing that pops into your mind?

Its multi-layered quality, right?

When you try to peel an onion, you always seem to discover a different skin below – no matter how long you spend peeling it. The “concentric circle” makeup of the onion is why ancient Egyptians saw it as a symbol of eternal life – and why they often buried onions with corpses inside tombs. In modern times, the numerous layers of an onion have been analogously used when describing the “layers” of personalities that people have.

In this way, your home’s roof is like an onion. From the outside, it may look like a single surface of shingles or similar roofing material; but in reality, there are many more layers underneath which help protect your home from moisture, outside air, and the elements.

Here’s a synopsis of the layers other than shingles that make up the roof of your home:

1. Flashing. These pieces of metal are placed over shingle and roof seams in valleys, along eaves, around chimneys, and near skylights or pipe vents. It provides an extra layer of protection against invading moisture.
2. Ridge vent. Though it’s made out of shingle material, the ridge vent is placed along the peak of your roof. But there’s also a gap between the ride vent and your roof to allow moist, warm air to pass from your attic to the home’s exterior.
3. Starter strips. These are placed immediately below the shingles on the lower roofline along the eaves. These specially-shaped shingles are positioned in the opposite direction as the rest of the shingles in order to help prevent shingle uplift during windy conditions.
4. Underlayment. This thin material makes up the layer right under the shingles. A sheet of underlayment can be made of felt, rubberized asphalt, fiberglass paper, or other materials, and it’s designed to keep liquid seeping through the gaps in the shingles from getting into your home.

5. Water shield. It’s mostly found neat the eaves, but it can be placed anywhere on the roof. This peel-and-stick product sits just below the underlayment and acts as a waterproof barrier to keep ice or water from building up.
6. Roof deck. This is the “floor” of the roof upon which all of the aforementioned materials are laid. It’s most commonly made up of plywood sheets that span the entire surface area of your roof.
7. Roof vents. Without these, warm air and moisture won’t escape from your attic, but may instead cause wood rot, mold, or mildew. Common spots for ventilation include a “pipe” vent near the top of the home, or a vent in the attic which lets air go out but prevents water from coming in.
8. Framing. This represents the joists, trusses, and beams which support the roof deck. Considered the “bones” of the roof, the framing must be strong enough to support all of the roofing materials it holds up.
9. Insulation. Fiberglass or spray-foam insulation is installed under the roof deck between the joists and beams. Inadequate insulation results in significant heat loss out of your home’s interior, which can lead to ice dams and higher energy costs.

If your roof is old and/or severely damaged, it may be time for a roof replacement. Harry Helmet has been replacing roofs for decades, and has the experience to not only properly install high-quality shingles, but will also identify and repair problems that may exist in the other layers of your roof. For a free, onsite cost estimate, give Harry Helmet a call at 1-888-5-HELMET, or fill out this form to schedule an appointment.

Written by Del Thebaud