Question 1

1. What are the best screws to use outdoors?

Accepted Answer

For long-term corrosion resistance, stainless steel exterior screws (especially A2 or marine-grade A4/316) offer outstanding durability, even in coastal or high-moisture conditions. However, depending on what you need, coated carbon steel screws, such as hot-dip galvanised or zinc-plated, deliver moderate resistance at a lower cost. Hot-dip galvanising performs better outdoors than electro-plated types, which may stain timber or degrade faster.

Question 2

2. Which outdoor screws won’t rust?

Accepted Answer

Most outdoor screws are rust-resistant, although not rustproof, designed to delay corrosion when used outdoors. Stainless steel screws are the most resistant to rust. Coated screws, such as galvanised or weatherproof screws, also offer good protection when used correctly.

Question 3

3. Are brass screws good for outdoors?

Accepted Answer

Brass screws resist corrosion but are relatively soft compared to stainless steel or carbon steel. This means they’re better suited for light outdoor fittings rather than heavy-duty structural use.

Question 4

4. Can I use indoor screws outside?

Accepted Answer

Indoor screws don’t have the same protective coatings as outdoor ones and will usually corrode quite quickly once they’re exposed to the elements. It’s best to always choose screws that are designed for external use.

Outdoor screws

Timco C2 Deck-Fix Exterior Premium Decking Screws Green TX20 4.5 x 65mm (1000 Pack) 65C2D1000

Carpenters Mate Exterior Wood Screws 63mm 500pk

Timco C2 Decking Screw 4.5 x 65mm 250no Tub

Reisser Cutter Screws 4 x 40mm (Box 200)

Wet Area Screws ST 42mm

Spax Frame Anchor Screw - Full Thread - Wirox Coated 7.5 X 80mm

Carpenters Mate Exterior Wood Screws 75mm 400pk

SPAX-D Decking Screws - C4 Wirox Tub Of 250 4.5 X 60mm

TIMCO Hexagonal Head In-Dex Timber Screws 150 x 6.7mm Olive Green

Spax T-Star Plus Flat CSK Wirox Coated T20 4.0 x 40mm

SPAX Wirox T-STAR Washer Head Screw 6.0 x 80mm

SPAX Wirox T-STAR Washer Head Screw 6.0 x 140mm

Spax Countersunk Wirox Construction Screws 6 x 120mm Pack of 100

Spax Wirox Construction Screws 6 x 160mm Pack of 100

Roofing Self Drilling Exterior Screws - 5.5 x 32mm - Pack of 100

Timco 4.5 x 75mm In-Dex Decking Screw PZ2 Tub of 250

Reisser Cutter Screws 3.5 x 16mm (Box 200)

Reisser Cutter Screws 4 x 60mm (Box 200)

Samac Performance Plus Woodscrews 90mm x 5.0mm - Box of 100

Samac Performance Plus Woodscrews 180mm x 6.0mm - Box of 100

Samac Performance Plus Woodscrews 130mm x 6.0mm - Box of 100

Samac Performance Plus Woodscrews 120mm x 5.0mm - Box of 100

Samac Performance Plus Woodscrews 60mm x 5.0mm - Box of 100

Optimaxx Extreme Performance Decking Screw 4.5x65mm Tub of 500

TIMCO C2 Decking Screw 4.5 Gauge 65mm L Organic Green Passivated