Synthetic Underlayment Fasteners
Every fastener you need to install synthetic underlayment to warranty spec — coil-fed plastic cap nails, cap staples, separate plastic caps, and the seam tape that goes with them. Sized for Everwin, Paslode, Bostitch N66BC-CT, Stinger CS150, and ProBilt PCN45 / PCS150.
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16 products
Stinger
Stinger CH38A Auto Hammer Cap Stapler, 3/8" | Contractor Pack
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Stinger
Stinger CS150B Cap Stapler, 5/8" to 1-1/2" | Contractor Pack
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Senco
Senco BC58 Button Cap Stapler w/Case, 5/8" | Contractor Pack
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Paslode
Paslode CS150 Pneumatic Cap Stapler, 1" to 1-1/2" | Contractor Pack
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Everwin
Everwin CAPTITE FSM40RBC Roll Cap Stapler, 1/2" to 1-9/16" | Contractor Pack
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Everwin
Everwin CAPTITE SCN25RBC Roll Cap Nailer, 1" | Contractor Pack
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Senco
Senco CS61H1 18GA Cap Stapler, 5/8” – 1-1/2” | Contractor Pack
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Stinger
Stinger 1" Stinger Plastic Cap 304 Stainless NailPac w/ Plastic Caps | Contractor Pack
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Everwin
Everwin FS9240BC 92 Series Cap Stapler, 5/8" to 1-9/16" | Contractor Pack
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Metabo HPT
Metabo HPT N3808APM Cap Stapler, 7/8" to 1-1/2" | Contractor Pack
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Roofing Gun
Stinger CH38-2 Hammer Cap Stapler, 3/8" | Contractor Pack
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Stinger
Stinger 1" Stinger Plastic Cap Electro-Galv NailPac w/Plastic Caps | Contractor Pack
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Stanley Bostitch
Stanley Bostitch N66BC-1 Cap Nailer, 1-1/4" to 2-1/2" | Contractor Pack
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Stanley Bostitch
Stanley Bostitch SL1838BC Cap Stapler Kit, 3/4" to 1-1/2" | Contractor Pack
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PneuTools
PneuTools PneuTools RCS150 Roll Cap Stapler, 5/8" to 1-1/2" | Contractor Pack
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Paslode
Paslode 3/8" x 1" Leg 18 Gauge Staple w/Plastic Cap | Contractor Pack
View productSynthetic underlayment fastener systems
| Model | System | Fastener | Compatible Guns | Best For |
|---|---|---|---|---|
| Coil cap nails | Coil cap nails | 1" cap + 1"–2" nail | Bostitch N66BC-CT, ProBilt PCN45, Stinger CN100 | Most common — synthetic + felt |
| Cap staples | Cap staples | 1" cap + 1" staple | Stinger CS150, ProBilt PCS150 | Faster cycle, lighter gun |
| Hand-cap method | Loose plastic caps + roofing nail | 1" cap + 1-1/4" coil nail | Standard coil roofing nailer | Backup or repair work |
All three systems are warranty-approved by major underlayment brands. Pick the one that matches the gun you own — most production crews run a dedicated cap nailer like the ProBilt PCN45.
Best pick for your job
Match the gun to the work — these are the picks pros reach for in each scenario.
Most production crews
Single-gun underlayment install.
Standard system — covered by every underlayment warranty.
Speed-focused crews
High-volume underlayment install.
Cap staplers cycle slightly faster than cap nailers.
Repair / backup work
Don't have a cap gun on the truck.
Use loose plastic caps with your standard 1-1/4" coil nailer for spot repair.
Foam board over sheathing
Continuous insulation systems.
Length to penetrate insulation + sheathing.
Tape + fastener bundle
Full underlayment system.
Tape the seams; cap-nail the field — full warranty system.
Cap nailer parts
O-rings, drivers, depth dial.
Keep your N66BC-CT or PCN45 in service.
Synthetic underlayment fastener systems explained
Three systems, all warranty-approved
Underlayment manufacturers (Owens Corning ProArmor, GAF Tiger Paw, Atlas Summit, Polyglass) approve three fastening systems for warranty: coil cap nails, cap staples, and the hand-cap method. Pick whichever matches your gun.
The most common is the coil cap nailer — Bostitch N66BC-CT, ProBilt PCN45, Stinger CN100, or Hitachi NV50AP3 — firing 1" cap + 1" nail combinations from a standard coil.
Cap nailer vs cap stapler
Cap nailers fire a coil-fed nail with the plastic cap pre-attached. Cap staplers fire a staple through a separate cap that's collated on a strip. Both deliver the same warranty-approved fastener pattern; the difference is gun ergonomics and cycle speed.
Cap staplers (Stinger CS150, ProBilt PCS150) tend to be slightly lighter and cycle faster. Cap nailers tend to be more durable and easier to rebuild long-term.
Spacing and pattern
Standard underlayment fastener spacing: 12" along laps, 24" in the field. High-wind zones tighten that to 6" along laps and 12" in the field. Always check the underlayment manufacturer's spec — Owens Corning ProArmor, GAF Tiger Paw, and Atlas Summit each have slightly different pattern requirements for warranty.
Frequently asked questions
Related guides & reviews
Synthetic vs felt underlayment
Why synthetic is now the standard.
Read guide →Cap nails vs cap staples
Which system to pick for your crew.
Read guide →Best cap nailers 2026
Tool picks for synthetic underlayment.
Read guide →Underlayment fastener spacing chart
Standard and high-wind patterns.
Read guide →Owens Corning ProArmor install guide
Manufacturer-spec fastener pattern.
Read guide →House wrap fastener guide
Cap nails for Tyvek and ZIP system.
Read guide →