Synthetic Underlayment Fasteners
Products
16 products
Stinger
Stinger CH38A Auto Hammer Cap Stapler, 3/8" | Contractor Pack
Stinger
Stinger CS150B Cap Stapler, 5/8" to 1-1/2" | Contractor Pack
Senco
Senco BC58 Button Cap Stapler w/Case, 5/8" | Contractor Pack
Paslode
Paslode CS150 Pneumatic Cap Stapler, 1" to 1-1/2" | Contractor Pack
Everwin
Everwin CAPTITE FSM40RBC Roll Cap Stapler, 1/2" to 1-9/16" | Contractor Pack
Everwin
Everwin CAPTITE SCN25RBC Roll Cap Nailer, 1" | Contractor Pack
Senco
Senco CS61H1 18GA Cap Stapler, 5/8” – 1-1/2” | Contractor Pack
Stinger
Stinger 1" Stinger Plastic Cap 304 Stainless NailPac w/ Plastic Caps | Contractor Pack
Everwin
Everwin FS9240BC 92 Series Cap Stapler, 5/8" to 1-9/16" | Contractor Pack
Metabo HPT
Metabo HPT N3808APM Cap Stapler, 7/8" to 1-1/2" | Contractor Pack
Roofing Gun
Stinger CH38-2 Hammer Cap Stapler, 3/8" | Contractor Pack
Stinger
Stinger 1" Stinger Plastic Cap Electro-Galv NailPac w/Plastic Caps | Contractor Pack
Stanley Bostitch
Stanley Bostitch N66BC-1 Cap Nailer, 1-1/4" to 2-1/2" | Contractor Pack
Stanley Bostitch
Stanley Bostitch SL1838BC Cap Stapler Kit, 3/4" to 1-1/2" | Contractor Pack
PneuTools
PneuTools PneuTools RCS150 Roll Cap Stapler, 5/8" to 1-1/2" | Contractor Pack
Paslode
Paslode 3/8" x 1" Leg 18 Gauge Staple w/Plastic Cap | Contractor Pack
What synthetic underlayment fasteners need that ordinary nails cannot deliver
Why synthetic changed the fastener rules
Synthetic underlayment changed roofing. It is lighter, stronger, holds up to weeks of exposure, and will not tear under foot. The trade off is that it cannot be fastened with bare staples or nails.
Without a plastic cap spreading the load, the underlayment will pull through at the head and end up in the next county. Everything on this page is rated and sized for synthetic underlayment work, and most of it works equally well for 30 pound felt and house wrap.
Three fastener types you will see
Collated cap nails feed a strip of plastic caps alongside a coil of nails into a dedicated cap nailer (Everwin CAPTITE, Paslode CS150, Metabo HPT NV50AP3). The gun joins the cap and nail at the moment of drive.
Collated cap staples use the same concept but the fastener is a wide crown staple instead of a nail. The two leg geometry holds synthetic underlayment a bit better in high wind. Loose 1 inch plastic caps are plain plastic caps with a center hole, used for hand driven installations or as backup when the cap tool runs out.
Picking the right tool for synthetic underlayment fasteners
Cap tools are a separate category from coil roofing nailers. Browse our cap nailers and cap staplers if you do not already own one. The Everwin CAPTITE is the workhorse choice for most pros. The Paslode CS150 trades a bit of capacity for lighter weight.
Standard fastening is 16 caps per 4x8 sheet, one every 12 inches along seams and one every 24 inches in the field. High exposure or hurricane zones bump that to 32 caps per sheet, every 6 inches along seams and every 12 inches in the field. Your underlayment manufacturer install guide will spell out the exact pattern, follow it for warranty coverage.
Frequently asked questions
- Why do synthetic underlayments need a plastic cap?
- Synthetic underlayments are stronger than felt but slipperier. A bare nail head will pull through under wind load before the shingles go down. The 1" plastic cap spreads the holding force across enough material that the underlayment stays put even with weeks of exposure.
- Cap nail vs cap staple — which holds better?
- Cap staples have two legs of grip and tend to hold synthetic underlayment slightly better against wind. Cap nails drive faster and work better on harder OSB. Most synthetic manufacturers list both as approved; check your specific product's installation instructions.
- Can I use a regular roofing coil nailer with plastic caps?
- No. Coil roofing nailers and cap tools are different machines. A coil nailer drives bare nails into the deck. A cap tool feeds a strip of plastic caps and a strip of nails or staples simultaneously, joining them at the moment of drive.
- How many cap fasteners per square of underlayment?
- Most synthetic manufacturers spec 16 to 32 caps per 4'x8' panel depending on wind zone. That works out to 50 to 100 caps per roofing square. A typical 1,000-cap collation will cover roughly 10 to 20 squares of underlayment.