Choosing the Right Decking Timber: What to Know About Price, Lifespan and Stock

If you’re planning a decking project, one of the first (and biggest) decisions you’ll face is what type of timber to use. From softwoods to hardwoods, each option has pros, cons and a price tag to match.

This guide breaks down the differences between the most popular timber types for decking, with clear advice to help you weigh up cost, durability and availability. Whether you’re a tradesperson pricing up materials or a homeowner starting your first deck, this one’s built around you.

What really matters when choosing decking timber

Before deciding on the type of timber to buy, it's helpful to understand the key factors that will affect your deck's performance and longevity.

Here’s what to think about from the start:

1. Match timber to your environment

• If your decking area is shaded or close to plants, it’s more prone to damp and rot. In this case, choose timber with higher natural durability or stronger treatment (like UC3/UC4-rated softwood).
• For sunny, exposed spots, UV protection matters. Oiling the boards or choosing UV-resistant finishes will prevent the timber from fading or cracking over time. For example, Cuprinol UV Guard Decking Oil 5L – Natural is a great option that protects while enhancing colour.

2. Think about maintenance

• Lower-cost timber can work just as well as premium hardwoods if you maintain it properly.
• This means regular cleaning, re-oiling, and checking for signs of wear – usually once or twice a year.
• For low-maintenance clear protection, try something like Cuprinol Total Deck Clear 5L, ideal for preserving the natural look of your wood.

3. Don’t forget fixings and finishes

• Using the right decking screws, clips, and sealants is just as important as choosing the timber itself.
• Look for rust-resistant or hidden fixings for a cleaner finish, like C2 Deck Fix Premium Decking Screws 65 mm for strength and durability, or Trex Deck Screws, 60mm, Dark Grey (Box of 350) for a discreet, colour-matched option.
• Don’t skip sealing either – Grain Guard Sealing Oil 1L is ideal for touch-ups or smaller decking areas.

4. Start with structure

• Even the best decking boards won’t last if they’re sitting on a poorly built subframe.
• Make sure the joists are treated timber, well-spaced, and allow for airflow underneath. Good ventilation prevents trapped moisture, which is the number one enemy of decking longevity.

 

Softwood vs hardwood decking: what you need to know

Here’s a side-by-side comparison of popular timber types you’ll find at MKM:

Timber Type	Typical Price Range	Durability	Key Benefits	Considerations
Treated Softwood	£	15–25 years (with treatment)	Affordable, easy to work with, widely available	Requires regular maintenance; shorter lifespan
Redwood (Treated)	££	20–30 years	Attractive grain, better natural resistance	Slightly higher cost; still needs upkeep
Hardwood (e.g. Balau)	£££	30+ years	High durability, minimal maintenance, premium look	Higher cost, heavier, may need pre-drilling

Durability estimates assume proper installation, treatment, and maintenance. Prices shown in relative terms (£ = lower cost, £££ = higher cost).

Affordable decking options from MKM

If you're looking for quality timber at competitive prices, MKM has you covered. Here are a few of our best-value options, available online or at your local branch:

Treated Softwood Decking Board – 32mm x 125mm

• Finish size: 27mm x 120mm
• Treatment: Pressure treated (UC3U)
• Best for: Low-cost builds, garden projects, starter decks
• Why choose it? A great budget-friendly option that still performs well with regular maintenance.

Treated Softwood Decking Board – 32mm x 150mm

• Finish size: 27mm x 145mm
• Treatment: UC3U
• Best for: Larger spans and longer runs
• Why choose it? The wider board gives more coverage, reducing the number of fixings and labour.

Imported Treated Redwood Deck – 28mm x 120mm x 4200mm

• Finish: Brown treated
• Length: 4.2m
• Best for: Mid-range projects with a bit more style
• Why choose it? Offers a more refined finish and better natural durability than standard softwood.

Decking timber for every budget

Whatever you’re working with – a tight budget or room to go premium – here’s a simple guide to help match the right timber to your spend:

Budget	Timber Type	Why It Works
Tight budget	Treated softwood (32 x 125mm or 32 x 150mm)	Lower upfront cost, easy to install, can last well with treatment
Mid-range	Redwood or wider boards	Better grain and natural resistance, longer lengths reduce joins
Premium	Hardwood (special order via branch)	Minimal upkeep, long lifespan, premium finish and feel

Not sure what’s best for your budget? Pop into your local MKM and have a chat with our timber specialists – they’ll help you get the best bang for your buck.

How to get your decking timber sorted without delays

There’s nothing worse than planning your project and hitting a supply snag. Here’s how to avoid delays and get decking timber that’s reliable and responsibly sourced:

• Check local branch stock – MKM branches carry popular sizes and lengths of decking timber in-store.
• Order online – Get materials delivered directly to the site or ready to collect.
• Ask about special orders – Need something specific, like hardwood decking or extra-long lengths? Our branch teams can help source to spec.
• Look for UC3 treatment – This pressure treatment is ideal for outdoor decking. All MKM-treated softwood decking boards meet this standard.
• Built to last – Our treated timber comes from certified suppliers and is designed for outdoor use. And don’t forget to include decking oils and screws in your order – it saves time and protects your investment.

So, which decking timber should you choose?

The best timber for your decking comes down to what you value most – upfront cost, long-term durability, or ease of maintenance.

• For affordable, practical builds, treated softwood is a top choice –maintain it well and it’ll go the distance.
• For a step up in performance and finish, redwood gives great value with a bit more character.
• If you’re after low-maintenance luxury, hardwood or modified timber may be worth the investment.

Whichever way you go, ensure the structure underneath is solid, the fixings are suitable for the job, and you have a plan for ongoing care.

Ready to get started?

Explore our full range of timber decking boards, decking oils, and decking screws or visit your local MKM branch to speak with our team. We’re here to help you build a deck that’s made to last – and made for you.