This is a long list that could go on indefinitely, so we’ll try to keep it moderately short.
Underlayment is a water-resistant or waterproof barrier installed directly onto your roof’s decking. Think of it as added protection from mother nature; wind, snow, and ice. Asphalt-saturated felt was pretty popular back in the day. Commonly referred to as felt paper or tar paper, it’s composed of bitumen or asphalt, polyester, and cellulose. Most roofers now will typically suggest Non-bitumen synthetic underlayment. The basemat (flexible base layer) is saturated in asphalt and adds fiberglass which gives it superior tear resistance and stability. If you’re looking for waterproof underlayment, Rubberized asphalt is your go-to. It contains higher percentages of asphalt and rubber polymers which makes it waterproof.
Price
Asphalt-Saturated Felt: $.05 – $.10 per sq ft. $105 – $210 for our example home.
Synthetic Underlayment:
Pipe boots/vents
These are installed to waterproof your plumbing vent pipes to prevent leakage. You’ll find them around any area of the home with appliances that need to breathe. Boots range from $275+ for 4 boots usually depending on the slope of your roof.
Ventilation
Most people currently have box vents or turbine vents. Instead, they should have ridge venting. Don’t be cheap.
Flashing
On brick homes, counter flashing is required (v expensive due to labor-intensive work), and step flashing is required around all roof-to-wall transitions & behind all types of non-brick siding.