How Long Should Decking Last?
What homeowners in Chichester & West Sussex should realistically expect
Decking should be a long-term feature of your garden — not something that needs replacing every few years. Yet many homeowners find their decking rotting, warping, or becoming unsafe far sooner than expected.
So, how long should decking actually last?
For gardens in Chichester and surrounding areas, the answer depends far more on how the deck is built than on the boards alone.
This guide explains realistic decking lifespans, what shortens them, and how to make sure your decking lasts properly.
The Short Answer
A well-built deck should last:
10–15 years for timber decking
20–30+ years for composite decking
If decking is failing within 5–7 years, it’s almost always due to poor design or installation, not “bad materials”.
What Determines How Long Decking Lasts?
1️⃣ The Subframe & Structure (Most Important)
The most common decking failures start below the boards.
A long-lasting deck requires:
Properly sized, pressure-treated joists
Correct spacing and support
Adequate ventilation beneath the deck
Protection from constant ground moisture
If the structure rots, the decking above it doesn’t matter.
2️⃣ Ground Contact & Moisture
Decking that sits too close to the ground or traps moisture will fail quickly.
Common issues include:
Joists in contact with soil
Poor airflow
Water pooling beneath the deck
In parts of West Sussex, damp ground conditions make correct clearance and drainage essential.
3️⃣ Timber vs Composite Boards
Timber decking
Natural appearance
Requires regular maintenance
More vulnerable to rot and movement
Shorter lifespan if neglected
Composite decking
Highly resistant to rot, warping, and splitting
Very low maintenance
Longer lifespan
More consistent over time
Board choice affects maintenance — structure affects longevity.
4️⃣ Footings & Supports
Decking needs stable, long-lasting support.
Options may include:
Concrete footings
Ground screws
Pads or piers
Insufficient or poorly installed footings lead to movement, uneven decks, and premature failure.
5️⃣ Exposure & Usage
Decking lifespan is also influenced by:
Shade vs direct sun
Wind exposure
Foot traffic
Furniture and load
High-use decks need stronger design and better materials.
Typical Decking Lifespan by Installation Quality
Installation QualityExpected LifespanPoor / rushed5–7 yearsAverage8–12 yearsProfessional, well-built15–30+ years
The difference is almost always in ground preparation and structure.
Signs Your Decking Is Failing Too Early
Warning signs include:
Soft or spongy boards
Rotting joists underneath
Excessive movement or bounce
Warping or splitting
Slippery, algae-covered surfaces
These aren’t just cosmetic — they’re safety issues.
Can Old Decking Be Repaired?
Sometimes.
Repairs may work if:
The structure is still sound
Only surface boards are affected
However, if the subframe is rotting or unstable, replacement is usually the only proper fix.
Replacing boards on a failing structure rarely lasts.
How to Make Decking Last as Long as Possible
To maximise lifespan:
Invest in proper ground preparation
Ensure good airflow under the deck
Use correct fixings and materials
Maintain timber decking regularly
Choose the right decking for your garden conditions
Doing it right once is always cheaper than rebuilding it later.
Decking Installations in Chichester & West Sussex
Local conditions matter. Soil type, drainage, and exposure all affect how decking performs long-term.
A professionally designed and installed deck:
Lasts longer
Feels solid and safe
Requires less maintenance
Adds real value to your garden
For a well build deck, visit our deck installation services, see examples of our work and book in your consultation/quote. it’s that easy.
