How many hidden clips do I need for a deck?

Roughly 1 clip per linear foot of decking board. For a 320 sqft deck with 16ft × 5.5″ wide boards = 44 boards × 16 ft = 704 lf = 704 clips. Buy 8 buckets at 90/each (Trex Hideaway) = 720 clips capacity. AZEK Cortex uses 0.85 clips/LF = 600 clips for same deck.

What's the difference between hidden clip brands?

Trex Hideaway, TimberTech CONCEALoc, Fiberon EDGEXpress, AZEK Cortex, Deckorators stainless — all proprietary, NOT interchangeable. Each works only with that brand's boards. Bucket sizes vary (90 to 175 clips). Pricing $65-115/bucket. AZEK Cortex is plug-and-screw (face-screw covered with color-matched plug) — discreet but not truly hidden. The other 4 are true hidden-clip systems.

Can I mix hidden clip systems with face screws?

Yes — board ends + butt joints ALWAYS use face screws (color-matched to board, separate from clip cost). The hidden clip holds the mid-span board edges between joists. Most systems include matching face screws in the bucket; AZEK Cortex sells them separately. Calculator surfaces both counts.

Are hidden clips worth the extra cost?

For composite + PVC: yes if you want premium aesthetic (no visible screw heads). Cost: $0.27-0.32 per clip vs $0.14 per face-screw. For 700 clips, hidden = $200 vs face screws = $100. The $100 premium for 'no screw heads visible' is worth it on premium boards (Trex Transcend, AZEK Vintage). For PT pine or entry composite, face screws are fine.

Do hidden clips work with all composite boards?

No — each system is brand-specific. Trex Hideaway only with Trex Enhance/Transcend. TimberTech CONCEALoc only with TimberTech/AZEK. Fiberon EDGEXpress only with Fiberon. The calculator's compatibility check flags incompatible board × system pairings before you order.

How do hidden clips attach to the joists?

Each clip has a stainless screw that goes through the clip body into the joist. The clip's wings extend up-and-out to grip the groove on the underside of the board. As boards are placed side-by-side, the wing edges fit into adjacent board grooves — one clip holds two boards. Spacing between boards is automatically set by the clip dimensions (typically 1/8-3/16″ — handles thermal expansion).

Can hidden clips be reused if I replace boards?

Yes — that's a major advantage. Pull up the clip's screw, lift the board, replace, reinstall. The clip itself is reusable indefinitely. Face screws CAN'T be reused — drill heads strip after one removal. For decks that might see board replacements (high-traffic, kid-prone), hidden clips pay off long-term.

What screws hold the hidden clips down?

Stainless steel #8 × 1-1/4″ pan-head screws (included in the bucket for Trex/TimberTech/Fiberon/Deckorators). Drives the clip body firmly to the joist top. AZEK Cortex uses a different system (the actual face-screw goes through the board into the joist; clip plugs cover the screw head). Always use the manufacturer-included screws — generic screws void the deck warranty.

How long does hidden-clip install take vs face screws?

Face screws: ~2 hours per 100 sqft of deck. Hidden clips: ~3-4 hours per 100 sqft (each clip needs to seat properly + screw aligned). For a 320 sqft deck: face screws = 6 hours; hidden clips = 10-12 hours. Pro crews shave 30% off both. DIY: budget 2× longer than these numbers.

Material · composite hidden fasteners

Hidden Clip Calculator

Composite + PVC hidden-fastener count across 5 brand-specific systems: Trex Hideaway, TimberTech CONCEALoc, Fiberon EDGEXpress, AZEK Cortex (plug-and-screw), Deckorators stainless. Auto-flags incompatible board × system combos. Bucket count + 2026-Q1 retail cost. Perimeter face-screws computed separately (board ends always use face screws — hidden clips only hold mid-span board edges).

By SemiSoftwares · DeckMath editorialReviewed against IRC 2021Updated July 2026

Start calculating

Get 2–3 free quotes

5 systemsCompatibility checkIRC R507.5

5·Brand systems

1/LF·Typical clip rate

Auto·Compat. check

$/bucket·Cost included

Inputs

Deck areasqft

sqft

Board lengthft

Joist spacingin OC

Hidden clip system

Board line2 compatible

Hidden clips · Trex Hideaway

7048 buckets · $520

44 boards704 lf

Clips needed

1.00/LF

Buckets

$520

Perimeter screws

included

All-in cost

clips + screws

System advisories

704 clips · 8 buckets · $520

Manufacturer spec

44 boards × 1.00 clips/LF × 16ft = 704 clips. Bucket of 90 at $65.

Color-matched perimeter screws included in bucket

Bucket contents

Trex Hideaway includes color-matched face screws for perimeter + butt joints. No separate screw purchase needed.

Hidden clip systems are brand-specific. Trex Hideaway × TimberTech boards = warranty void. Always match system to board brand. 2026-Q1 retail.

Get matched

Want 2–3 free quotes for this exact deck?

We'll send your plan to vetted local builders. Free, no obligation.

How to use

How to use the hidden clip calculator in 4 steps.

Enter deck area + board length + joist OC

Standard 16″ joist OC for face screws; 12″ OC required if hidden-clip + composite + spans > 16 ft.

Pick hidden clip system

Trex Hideaway (Trex boards only, $65/90-bucket). TimberTech CONCEALoc (TimberTech + AZEK, $72). Fiberon EDGEXpress (Fiberon only, $115/175-bucket). AZEK Cortex (plug-and-screw, $89 + no screws). Deckorators stainless (Voyage/Vault, $78).

Pick board line

Calculator validates compatibility. Trex Hideaway × TimberTech boards = INCOMPATIBLE flag. The brand-specific systems are not interchangeable.

Read clip count + bucket count + screws

Total clips needed + buckets to buy (90-175 per bucket). Perimeter face-screws computed separately (board ends always need face screws — hidden clips only hold mid-span board edges).

How we calculate

How DeckMath calculates this — IRC 2021 sources.

The Hidden Clip Calculator counts hidden fasteners for composite + PVC deck boards across 5 brand-specific systems (Trex Hideaway, TimberTech CONCEALoc, Fiberon EDGEXpress, AZEK Cortex, Deckorators stainless). Each system has different clip-per-LF rate, bucket size, price, and compatibility matrix. Auto-flags incompatible board × system pairings. Computes color-match perimeter screws separately (board ends always need face screws even with hidden systems). 2026-Q1 retail.

IRC references

IRC R507.5 — Decking attachment with corrosion-resistant fasteners
Manufacturer specs: Trex/TimberTech/Fiberon/AZEK/Deckorators hidden-clip systems

Verify against the published source: 2021 International Residential Code (ICC).

Manufacturer specs: Trex/TimberTech/Fiberon/AZEK/Deckorators hidden-clip systems. Bucket pricing 2026-Q1 big-box retail.

Board count

boards = ceil(deck_area / (board_length × 0.458))

5.5″ wide board face = 0.458 ft. A 320 sqft deck with 16ft boards = 320 / 7.33 = 44 boards.

Clips needed

clips = ceil(total_lf × clips_per_lf)

Most systems use 1 clip per LF (1 clip per joist intersection on 16″ joists). AZEK Cortex uses 0.85 (different geometry). 44 boards × 16 ft = 704 lf × 1 clip/lf = 704 clips.

Buckets

buckets = ceil(clips / bucket_size)

Trex 90-bucket: 704 / 90 = 7.8 → 8 buckets. Fiberon 175-bucket: 704 / 175 = 4.02 → 5 buckets (denser pack = fewer trips to checkout).

Perimeter screws

screws = ceil(perimeter_lf × 2)

Board ends face screws-only (hidden clips don't extend to perimeter). 2 screws per LF of perimeter + butt joints. Most systems include color-matched perimeter screws; AZEK Cortex separates them.

Save your plan

Don’t lose this estimate.

Your inputs are preserved in the URL — email it to yourself or copy the link so you can compare with contractor bids later. No account needed.

Hidden clip questions, answered.

Roughly 1 clip per linear foot of decking board. For a 320 sqft deck with 16ft × 5.5″ wide boards = 44 boards × 16 ft = 704 lf = 704 clips. Buy 8 buckets at 90/each (Trex Hideaway) = 720 clips capacity. AZEK Cortex uses 0.85 clips/LF = 600 clips for same deck.
Trex Hideaway, TimberTech CONCEALoc, Fiberon EDGEXpress, AZEK Cortex, Deckorators stainless — all proprietary, NOT interchangeable. Each works only with that brand's boards. Bucket sizes vary (90 to 175 clips). Pricing $65-115/bucket. AZEK Cortex is plug-and-screw (face-screw covered with color-matched plug) — discreet but not truly hidden. The other 4 are true hidden-clip systems.
Yes — board ends + butt joints ALWAYS use face screws (color-matched to board, separate from clip cost). The hidden clip holds the mid-span board edges between joists. Most systems include matching face screws in the bucket; AZEK Cortex sells them separately. Calculator surfaces both counts.
For composite + PVC: yes if you want premium aesthetic (no visible screw heads). Cost: $0.27-0.32 per clip vs $0.14 per face-screw. For 700 clips, hidden = $200 vs face screws = $100. The $100 premium for 'no screw heads visible' is worth it on premium boards (Trex Transcend, AZEK Vintage). For PT pine or entry composite, face screws are fine.
No — each system is brand-specific. Trex Hideaway only with Trex Enhance/Transcend. TimberTech CONCEALoc only with TimberTech/AZEK. Fiberon EDGEXpress only with Fiberon. The calculator's compatibility check flags incompatible board × system pairings before you order.
Each clip has a stainless screw that goes through the clip body into the joist. The clip's wings extend up-and-out to grip the groove on the underside of the board. As boards are placed side-by-side, the wing edges fit into adjacent board grooves — one clip holds two boards. Spacing between boards is automatically set by the clip dimensions (typically 1/8-3/16″ — handles thermal expansion).
Yes — that's a major advantage. Pull up the clip's screw, lift the board, replace, reinstall. The clip itself is reusable indefinitely. Face screws CAN'T be reused — drill heads strip after one removal. For decks that might see board replacements (high-traffic, kid-prone), hidden clips pay off long-term.
Stainless steel #8 × 1-1/4″ pan-head screws (included in the bucket for Trex/TimberTech/Fiberon/Deckorators). Drives the clip body firmly to the joist top. AZEK Cortex uses a different system (the actual face-screw goes through the board into the joist; clip plugs cover the screw head). Always use the manufacturer-included screws — generic screws void the deck warranty.
Face screws: ~2 hours per 100 sqft of deck. Hidden clips: ~3-4 hours per 100 sqft (each clip needs to seat properly + screw aligned). For a 320 sqft deck: face screws = 6 hours; hidden clips = 10-12 hours. Pro crews shave 30% off both. DIY: budget 2× longer than these numbers.

Embed this calculator

One line. Any site. Free.

Drop the snippet into your contractor site, blog, or marketing page. Theme matches the parent site automatically.

<!-- Hidden Clip Calculator — free embed by DeckMath -->
<a href="https://deckmath.com/calculators/hidden-clip-calculator"
   data-deckmath-calc="hidden-clip-calculator"
   data-theme="auto">Hidden Clip Calculator by DeckMath</a>
<script src="https://embed.deckmath.com/v1.js" async></script>

The credit link is a normal attribution — please keep it in. It's how DeckMath stays 100% free, with no signup and no ads inside the widget.

One tool · free · no signup

Plan the whole project, not just one number

The Deck Project Planner turns your dimensions into a complete material list, cost, 3D preview, and a PDF you can take to the lumber yard — all in one place.

Open the planner Find my material

Deck Fastener Calculator

Exact deck-screw + clip + nail count for any deck. 4 fastener systems × board geometry × joist spacing = total + 350-box count + 2026-Q1 retail cost. Stair-tread math separate.

Composite Deck Cost Calculator

Trex, TimberTech, Fiberon, Deckorators by line + color. Real installed cost + 25-yr TCO vs pressure-treated. 2026 retail pricing.

Trex Deck Calculator

Trex deck cost + BoM. All 4 lines (Transcend incl. Lineage, Select, Enhance), full palette, TUHF box count, RainEscape, DeckLighting.