Garden Decking Guide for Somerset Homes: Planning, Materials & Construction Advice

Decking can be an excellent way to create usable outdoor space, particularly in gardens where levels change or where a raised seating area would provide better views or sunlight.

When designed and built properly, a deck can function much like an outdoor room — providing space for dining, relaxing or entertaining.

Across Somerset, from town gardens in places such as Frome or Wells to larger rural properties around Bruton or Castle Cary, decking is often chosen where a patio would be difficult or expensive to construct due to level changes.

This guide highlights some of the key things homeowners should consider when planning a decking project.

Start With the Purpose and Position

Before deciding on materials or construction details, it’s important to think about how the deck will actually be used.

Common uses include:

• Outdoor dining
• Relaxed seating areas
• BBQ or outdoor kitchen zones
• Connecting the house to the garden
• Viewing platforms in sloping gardens

The size and position of the deck should suit its intended purpose.

Also consider:

• Sun orientation (north, south, east or west facing)
• Whether shade will be needed in summer
• Privacy from neighbouring properties
• How the deck connects to existing paths or lawns

A deck should feel like a natural extension of the house and garden.

Choosing Decking Boards

The decking boards themselves are one of the most visible elements, and there are several common options.

Pressure Treated Softwood

This used to be the most widely used option and is generally the most affordable.

Advantages include:

• Lower material cost
• Easy to work with
• Widely available

However, softwood decking will usually require regular treatment and maintenance to maximise its lifespan.

Hardwood Decking

Hardwood boards are denser and more durable than softwood.

Benefits may include:

• Greater natural durability
• Attractive grain and colour
• Longer lifespan if properly installed

Hardwood decking is typically more expensive but can provide a very high-quality appearance.

Composite Decking

Composite decking boards are manufactured from a mixture of recycled plastics and wood fibres.

Typical advantages include:

• Low maintenance
• Consistent appearance
• Resistance to rot and insect damage

Composite boards are often used for modern garden designs where minimal upkeep is desired. Our favourite brand of composite is Millboard.

Deck Framing Options

The structural frame beneath the deck is critical to its long-term stability.

Frames are usually constructed using:

• Pressure treated timber joists
• Composite framing systems

Timber frames remain the most common approach, provided the timber is suitable for external use and properly installed. Although Composite appears a good option in principal, its cost often prohibits its use, both in material cost & the additional labour it involves.

Deck Framing Design Principles

Proper structural design is essential for a safe and durable deck.

Typical good practice includes:

• Joists spaced at 400mm centres
• 150mm × 50mm joists commonly used for many domestic decks
• Installation of noggins between joists to prevent twisting
• Adequate support to prevent sagging
• Use of suitable corrosion-resistant fixings

Additional considerations may include:

• Weed barrier membranes beneath the deck
• Ground preparation to reduce vegetation growth
• Allowing ventilation beneath the structure

A well-built frame is one of the most important factors affecting the lifespan of the deck.

Foundations and Structural Support

Decks can be supported in several ways depending on height and ground conditions.

Common approaches include:

• Timber posts set into concrete foundations
• Concrete block plinths supporting the frame
• Concrete pads formed using slabs set on concrete
• Full concrete bases for specific situations

Raised decks require particularly careful design to ensure the structure remains stable over time.

Deck Height and Levels Against the House

One detail that is often overlooked is the relationship between the deck and the house itself.

Typical considerations include:

• Keeping the deck around 150mm below the damp-proof course
• Aligning the deck with door thresholds where appropriate
• Ensuring water cannot collect against the building

Correct detailing at this point helps prevent moisture problems and ensures safe access from the house.

Raised Decks and Two-Level Designs

Decking is particularly useful in gardens with level changes.

Design options may include:

• Two-tier decks connected by steps
• Raised platforms overlooking the garden
• Decking integrated with patios or pathways

Raised decks can also create useful space beneath the structure.

Under-Deck Storage

Where a deck is raised above ground level, the space beneath can sometimes be used for storage.

This might include:

• Garden equipment
• Outdoor furniture storage
• Discreet bin storage

Proper planning may be required to ensure this area remains accessible and well ventilated.

Handrails and Balustrades

Where decks are raised, safety and appearance both need to be considered.

Handrail options may include:

• Timber balustrades
• Metal rail systems
• Glass panels
• Composite railings

The choice will often depend on the overall style of the garden and the height of the deck.

Deck Design Details

Thoughtful design details can make a deck feel more integrated into the garden.

Possible features include:

• Curved deck edges
• Contrasting border boards
• Different board laying directions
• Built-in planting pockets
• Integrated seating

These elements help turn a simple deck into a more refined garden feature.

Decking vs Patio – Cost Considerations

Homeowners sometimes choose decking as a cost-saving alternative to patios.

This can depend heavily on the situation.

For ground-level installations, the cost difference may be relatively small once proper framing and materials are included.

However, where a garden requires a raised outdoor space, decking can sometimes provide substantial savings.

Creating a raised patio at the same level may require:

• Retaining walls
• Extensive sub-base preparation
• Significant groundworks

In these situations, a deck structure can sometimes be a more practical solution.

Maintenance and Longevity

The lifespan of a deck depends heavily on materials, construction quality and maintenance.

Maintenance may include:

• Periodic cleaning
• Re-treating timber boards
• Checking fixings and structural elements
• Clearing debris from between boards

Composite decking generally requires less maintenance but still benefits from occasional cleaning.

DIY or Professional Installation?

Some smaller decking projects can be completed as DIY builds.

However, homeowners should consider:

• The size and complexity of the project
• Structural safety
• Required tools

Typical tools for decking construction may include:

• Chop saw
• Circular saw
• Jigsaw
• Impact driver
• Spirit levels and framing squares

For larger or raised decks, it is often advisable to work with an experienced decking contractor who understands the structural requirements involved.

Planning Permission Considerations

In many situations, decking can be built under permitted development rules.

However, in England planning permission may be required if:

• The deck platform is more than approximately 300mm above ground level, or
• The deck significantly alters the level of the garden.

Local planning rules can vary, so it is always advisable to check with your local authority before construction begins.

Bringing the Design Together

A well-designed deck balances structure, materials and how the space will actually be used.

For homeowners across Somerset planning a new decking area, careful design helps ensure the finished space works comfortably with both the house and the wider garden.

Whether used as a simple seating platform or part of a larger garden layout, thoughtful planning can help create an outdoor space that remains attractive, practical and durable for many years.

If you are interested in our bespoke design service for your deck, which will take advantage of our in-house, extensive hands on build experience of constructing decks over a 25yr period, then we’d love to here from you.