How Many Roofing Nails per Square for Shingles and Underlayment

If you are currently planning to install roofing shingles or its underlayment, then there are some factors that you need to consider, such as the roofing material weight, building’s foundation, and framing, etc.

To assess the installment process accurately, then you need to know how many roofing nails per square are required inexact. Please find out how to calculate them correctly here.

How Many Roofing Nails per Square

How Many Cap Nails per Square Of Underlayment

The roof is indeed one of the most crucial elements of the building’s structure. To install the roofing successfully, then one needs to invest a significant amount of money and time. A minor mistake might cost you pricey fixing work, so it’s always recommended to hire or at least discuss your roofing project with a professional roofer or contractor.

That being said, there are some simple matters that you can do yourself, such as doing simple math over how many roofing nails per square of underlayment that you need. Though of course, you need to know your roof size first to do the estimation.

Read also: Underlayment for Metal Roof

The key to performing a successful roofing project is knowing how much height the roof must bear – which is crucial information if you work with aged framing and foundation. One of the factors that add up the roof weight estimation is the nails’ weights that will hold the roof underlayment and shingles in their place.

The majority of roofing manufacturers advise that you use four nails for each shingle for the roofing main area and use five nails for each roofing underlayment square. This means that you’ll need 320 nails per square foot. For you who live in windy areas, you may want to use 480 nails per square.

The most commonly used nail type is the 1.5” roofing nail, which has 7/16” flathead and 11-gauge smooth shank. The nails are resistant to extreme weather such as rain or sun because they’re hot galvanized.

This type of nail weighs 1 lbs for 140 nails. In general, you’ll need about 2 ¼ lbs. of nails for each underlayment square and 3 ½ lbs. if the area is particularly windy.

Nails are usually sold in pounds, so you’d be able to ask the supplier for the accurate amount and length of nails according to your roof size.

How Many Cap Nails per Square Of Synthetic Underlayment

Synthetic underlayment has existed since the early 2000s with various types available. You can find spun or woven synthetics that are created from polypropylene or polyethylene. Each type has different characteristics, such as thickness, manufacturing procedure, walkability, and exposure time, but generally, the ingredients are quite similar.

How Many Cap Nails per Square Of Synthetic Underlayment

Synthetic underlayment is usually differentiated to their weight and their feeling. The unit used to estimate the synthetics are grams-per-square-meter (GSM).

How many roofing nails per square of synthetic underlayment required is the same as the common underlayment calculation above. However, most roofing contractors choose to use staples instead of nails for this material. The staples are places once every 4” or 8”, then they are secured with a second underlayment layer with staples once every 2” to 3”.

How Many Nails per Square Of Cedar Shingles

Cedar is a solid choice of material for roof shingles. It usually comes with natural preservatives to fight UV rays, damage, moisture, and infestation. It has wind-resistant quality naturally, so cedar shingle might be an ideal selection if you use it in windy areas.

So, how many nails per shingle that cedar roofing material need? In general, four to five nails per shingle would be sufficient. The standard required amount of nails for cedar shingles is 320 pieces per square.

For areas with a lot of wind, six nails for each shingle might be needed, which means you need 480 nails for each square. This latter calculation is also applied if you use mansard roofing.

You should always refer to the shingles or underlayment application instructions before and during the installation process, including seeing the correct nailing pattern.

Don’t hesitate to ask someone who knows more about the roofing installation project about how many roofing nails per square you should use. The last, you should also check the local building regulation in your area regarding roofing.